SSM-SU-5297.1
SUBSEA PIPELINE CONSTRUCTION
APPLICATION: SUBSEA
This document is the confidential property of Chevron U.S.A. Inc. and its
affiliates. When made available to any contractor providing services to
Chevron U.S.A. Inc. or its affiliates, the contractor's use of this document shall
be governed by the confidentiality provisions of the applicable contract or bid
package. Without limiting the foregoing, neither the whole nor any part of this
document may be disclosed by the contractor to any third party, other than an
affiliate of the contractor that requires this information for purposes of the
contract with the Chevron entity, without the prior written consent of the
Chevron entity that has disclosed this document to the contractor. When
requested by Chevron U.S.A. Inc. or its disclosing affiliate, the contractor must
return all copies of this document to the Chevron entity requesting such return
and delete any electronic copies from the contractor's systems.
Any and all modifications (changes, amendments, etc.) to this document must
follow approved Chevron Engineering Standards governance processes.
Rev
Date
08/12
12/13 (E)
Description
Initial release
Updated titles of PPL-SU-1050 and
PPL-SU-4737.
Author
CHK
APP
Sponsor
SMEB
APHD
n/a
n/a
S. Mebarkia
A. Palisch
Replaced references to SSM-SU-54.08 with
SSM-SU-5408
5297.1
02/15
Technical update. Replaced references to:
SSM-SU-50.03 with SSM-SU-5003
SSM-SU-54.07 with FFS-DU-5407
COM-SU-2.02 with COM-SU-202
Removed references in Appendix A to:
SSM-SU-50.01
SSM-SU-50.02
SSM-SU-50.04
Added reference in Appendix A to:
COM-SU-6092
SSM-SU-6095
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CONTENTS
1.0
Scope ..........................................................................................................................5
2.0
References ..................................................................................................................5
2.1
2.2
2.3
Purchaser Documents ......................................................................................5
Industry Codes and Standards .........................................................................5
Conflict Resolution and Deviations ...................................................................5
3.0
Acronyms ....................................................................................................................6
4.0
General Requirements ...............................................................................................7
4.1
4.2
4.3
5.0
Meetings ......................................................................................................................8
5.1
5.2
5.3
5.4
5.5
6.0
Applicable Standards and Regulations ............................................................8
Units of Measure ..............................................................................................8
Software ...........................................................................................................8
Offshore Progress Meetings .............................................................................8
Worksite Progress Meetings ............................................................................9
Pre-Construction Meeting .................................................................................9
Kick-Off Safety Meetings ..................................................................................9
Purchaser Meetings .......................................................................................10
Documentation .........................................................................................................10
6.1
6.2
6.3
6.4
Submittals with Bid .........................................................................................11
Submittals Before Pipe Assembly ..................................................................11
Submittals Before Starting Operations at Site ................................................12
Installation Manual .........................................................................................12
7.0
Quality Assurance and Control ..............................................................................14
8.0
Material ......................................................................................................................15
8.1
8.2
9.0
Acceptance, Storage, and Transport of Material ..................................................16
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
10.0
Material Provided by Purchaser ....................................................................15
Material Provided by Supplier .......................................................................15
Material Control Procedure ............................................................................16
Storage ...........................................................................................................17
Receipt of Line Pipe .......................................................................................18
Receipt of Purchaser-Supplied Material .........................................................19
Handling .........................................................................................................20
Transportation ................................................................................................21
Material Traceability .......................................................................................22
Cleanup, Pollution Control, and Damages .....................................................22
Pipe Joint Fabrication ..............................................................................................23
10.1
10.2
10.3
10.4
10.5
Multiple Joints .................................................................................................24
Stalks and Half Stalks ....................................................................................24
Tie-In Spools (Between SCR and Host Platform) ..........................................25
Subsea Tie-In Spools .....................................................................................25
Additional Pipe Identification after Fabrication ...............................................26
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11.0
Pipelay Equipment and Required Personnel .........................................................26
11.1
11.2
11.3
11.4
11.5
11.6
11.7
11.8
12.0
Installation Spread ..........................................................................................26
Installation Trials ............................................................................................28
Dynamic Positioning System Trials ................................................................28
Personnel Transportation ...............................................................................29
Communication ..............................................................................................29
Diving Operations ...........................................................................................29
Remotely Operated Vehicles ..........................................................................30
Positioning System .........................................................................................31
Construction Operations .........................................................................................33
12.1
12.2
12.3
12.4
12.5
12.6
13.0
SSM-SU-5297.1
General ...........................................................................................................33
Pipeline Monitoring and Control .....................................................................33
Supplier Reporting ..........................................................................................35
Supplier Safety ...............................................................................................36
Supplier Anchor Handling, Mooring, and DP Requirements ..........................38
Pipeline Abandonment and Recovery ............................................................39
Welding .....................................................................................................................40
13.1
13.2
General ...........................................................................................................40
Weld Repairs ..................................................................................................40
14.0
Field Joint Coating ...................................................................................................40
15.0
Field Repairs to Pipeline Coating Damage ............................................................40
15.1
15.2
15.3
15.4
15.5
15.6
15.7
15.8
15.9
15.10
16.0
Anode Attachment and Coating Repairs ...............................................................45
16.1
16.2
16.3
16.4
16.5
17.0
General ...........................................................................................................40
Damage and Repair During Handling ............................................................41
Corrosion Coating ..........................................................................................41
Riser Coating Damage and Repair ................................................................41
Concrete Weight Coating ...............................................................................41
Testing of Coating Repairs .............................................................................43
Pipe Damage ..................................................................................................43
Damage and Repair During Installation .........................................................43
Weight Coating Damage Detected Below Water ...........................................44
Deepwater Pipeline Repair .............................................................................44
General ...........................................................................................................45
Anode Attachment ..........................................................................................45
Corrosion Coat Repair (After Anode Attachment) ..........................................45
Concrete Weight Coating Repair (After Anode Attachment) ..........................45
Inspection and Acceptance ............................................................................45
Pipeline Riser Installation .......................................................................................45
17.1
17.2
17.3
17.4
17.5
17.6
17.7
General ...........................................................................................................45
Conventional Risers .......................................................................................46
J-Tube Risers .................................................................................................47
Pre-Installed Risers ........................................................................................50
Steel Catenary Risers ....................................................................................50
Flexible Riser ..................................................................................................51
Hybrid Riser and Top Tension Risers ............................................................51
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18.0
Pipeline Burial and Trenching ................................................................................51
19.0
Insulating Flanges ....................................................................................................51
20.0
Offshore Installation ................................................................................................51
20.1
20.2
20.3
20.4
20.5
20.6
20.7
20.8
20.9
20.10
20.11
20.12
21.0
Shallow Water Installation .......................................................................................59
21.1
21.2
22.0
General ...........................................................................................................59
Pipelaying .......................................................................................................60
Deepwater Installation Control ...............................................................................61
22.1
22.2
22.3
23.0
Pipeline Alignment and Tolerances ................................................................51
Installation ......................................................................................................52
Pull Tube Operation .......................................................................................54
Holiday Detection ...........................................................................................56
Abandonment and Recovery ..........................................................................56
Pickup and Laydown ......................................................................................57
Buckle Initiation ..............................................................................................57
Protection of Nearby Existing Structures ........................................................57
Pipeline Spanning ..........................................................................................57
Acceptance Testing ........................................................................................58
Touchdown Monitoring ...................................................................................58
Subsea Structures Installations ......................................................................58
Allowable Strain ..............................................................................................61
Local Buckling and Ovalization ......................................................................62
Monitoring Pipelay ..........................................................................................62
Monitoring and Inspection ......................................................................................63
23.1
23.2
23.3
23.4
23.5
23.6
23.7
Pipeline Welding and NDE .............................................................................63
Production Inspection and Testing .................................................................63
Notification ......................................................................................................64
Purchaser Inspection ......................................................................................64
Coating Inspection ..........................................................................................64
Subsea Inspection ..........................................................................................64
Pipeline Spans ...............................................................................................65
24.0
Crossings of Foreign Pipelines ..............................................................................66
25.0
Right-of-Way .............................................................................................................67
26.0
Pipeline Installation Manual ....................................................................................67
27.0
As-Built Documentation ..........................................................................................68
27.1
27.2
General ...........................................................................................................68
Video Requirements .......................................................................................69
Appendix A Additional References .................................................................................71
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1.0
SSM-SU-5297.1
SCOPE
This specification defines the minimum requirements for the construction and installation of
subsea pipelines.
2.0
REFERENCES
1. The following documents are referenced herein and are considered part of this specification.
2. Unless otherwise specified in Section 2.1 or Section 2.2, use the latest edition of the
referenced documents.
3. Refer to Appendix A for additional references not cited in the text of this specification.
2.1
2.2
Purchaser Documents
SSM-SU-5003
Welding and Inspection Requirements for Subsea Pipelines and
Fixed Risers
SSM-SU-52.01
Cathodic Protection of Subsea Pipelines
SSM-SU-54.06
ROV Systems
SSM-SU-54.14
Fatigue Testing of Pipeline and Riser Girth Welds Subject to Cyclic
Loading
SSM-PU-54.17
Remotely Operated Vehicle System Auditing
SSM-IT-54.17
Inspection and Testing Requirements Sheets for Remotely Operated Vehicle
System Auditing
SSM-DU-5281
Cathodic Protection of Subsea Facilities
Industry Codes and Standards
American Petroleum Institute (API)
RP 2RD
Design of Risers for Floating Production Systems (FPSs) and Tension-Leg
Platforms (TLPs)
RP 5L1
Recommended Practice for Railroad Transportation of Line Pipe
RP 5LW
Recommended Practice for Transportation of Line Pipe on Barges and
Marine Vessels
Std 1104
Welding of Pipelines and Related Facilities
Det Norske Veritas (DNV)
Rules for Classification of Ships
Part 6, Chapter 7 – Dynamic Positioning Systems
National Association of Corrosion Engineers (NACE)
SP0169
2.3
Control of External Corrosion on Underground or Submerged Metallic
Piping Systems
Conflict Resolution and Deviations
1. Conflicts between documents shall be submitted to Purchaser in writing for resolution.
If requirements between different documents are in conflict, in general, the more stringent
requirements shall apply.
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2. Deviations and exceptions from codes, standards, and references listed herein shall require
notification and acceptance by Owner before they are considered acceptable.
3. This specification shall not conflict with local regulatory requirements. In the event of
conflict, the more stringent requirements shall apply.
4. Supplier shall obtain Owner written acceptance for any deviations from the requirements of
this specification or specifications, standards and drawings referenced herein.
5. The omission of any essential items within this specification shall not relieve Supplier of any
duty or obligation necessary for the complete installation and testing of the facilities ready for
use and operation.
3.0
ACRONYMS
A&R—Abandonment and Recovery
CVA—Certifying Verification Authority
DGPS—Differential Global Positioning System
DP—Dynamic Positioning
ESD—Emergency Shutdown
FBE—Fusion Bonded Epoxy
FPS—Floating Production System
HAZID—Hazard Identification
HAZOP—Hazardous Operations
HES—Health, Environment, and Safety
IIF—Incident and Injury Free
LAT—Lowest Astronomical Tide
MOC—Management of Change
MPI—Magnetic Particle Inspection
MWS—Marine Warranty Surveyor
NCR—Non-Conformance Report
NDE—Nondestructive Examination
NDT—Nondestructive Testing
OSHA—Occupational Safety and Health Administration
PLET—Pipeline End Termination
QACP—Quality Assurance and Control Program
RAO—Response Amplitude Operator
ROV—Remotely Operated Vehicle
RTJ—Ring-Type Joint
SCR—Steel Catenary Riser
SMYS—Specified Minimum Yield Strength
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SSIV—Subsea Isolation Valve
TDP—Touchdown Point
TLP—Tension Leg Platform
TTR—Top Tensioned Riser
VIP—Value Improvement Practice
WD—Water Depth
WPQ—Welding Procedure Qualification
WQT—Welding Qualification and Testing
4.0
GENERAL REQUIREMENTS
1. Supplier shall prepare the procedures necessary for pipelay operations, and shall perform
engineering analyses (e.g., lay stress analysis and abandonment and recovery [A&R] analysis)
and calculations required to plan and execute the work in compliance with this specification.
2. Pipe and other material shall be transported, received, and controlled by Supplier both onshore
and offshore in preparation for the selected method of installation.
3. Supplier shall provide the following:
a. Pipeline initiation.
b. Monitoring of the stress and strain levels in the pipe during each stage of pipelay
operation, including initiation, A&R, and installation of inline structures.
c. Remotely operated vehicle (ROV) or other type of monitoring support during pipelay,
crossing, and pull-in operations.
d. Free span corrections.
e. Completion of tie-in spools, if applicable.
f.
As-built survey.
g. Final documentation.
4. The following elements shall be part of pipeline installation described herein:
a. Rigid steel pipelines.
b. Steel catenary risers (SCRs).
c. Anodes, if applicable.
d. Pipeline end terminations (PLETs).
e. In-line structures.
f.
Crossing supports.
g. Pipeline and riser protection.
5. Supplier shall provide support for surveying, positioning, communication, and
accommodations associated with the construction and installation of pipeline.
6. Unless specified otherwise, elevations on drawings and sketches shall be referenced to lowest
astronomical tide (LAT), and LAT shall appear as elevation 0.0 feet (0.0 m).
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7. This document is not intended to be all inclusive, and use of the requirements set forth shall
not relieve Supplier of responsibility for supplying a product capable of performing its
intended service.
8. The omission of any essential items within this specification shall not relieve the Supplier of
the obligation to complete installation and testing of the facilities so they are ready for use and
operation in accordance with the project scope of work and technical requirements.
9. Supplier shall perform the work in a safe manner. Throughout the duration of the project,
Purchaser health, environment, and safety (HES) guidelines shall be strictly adhered to by
Supplier and sub-Suppliers.
4.1
Applicable Standards and Regulations
1. Pipeline construction and installation, including installation design analysis, shall be
performed in accordance with this specification and the references listed herein.
2. Supplier shall ensure that pipeline and riser installation complies with current governing
regulations and national best practices, including this specification and the references listed
herein.
4.2
Units of Measure
1. Unless specified otherwise, U.S. Customary Units shall be the preferred dimensional system in
U.S.A., and SI units outside U.S.A. Units of measure shall be used consistently in all design
calculations, computer analyses, drawings, and documentation.
2. If metric units provide more conventional or accurate means of reporting results, metric units
may be used for drawings.
4.3
Software
1. Software description, capabilities, verification, and quality assurance process shall be
submitted to Purchaser.
2. Computer programs used for design and analysis shall be subject to prior Purchaser
acceptance.
5.0
MEETINGS
5.1
Offshore Progress Meetings
1. A progress meeting shall be held by Supplier at least once a day during offshore construction,
to discuss progress and problems and to verify that all Supplier supervisory personnel are
familiar with procedures for the next 24 hours.
2. These meetings shall be chaired by Supplier’s construction superintendent.
a. Foremen, field engineers, the vessel captain, and Supplier’s safety supervisor shall attend
these meetings as a minimum.
b. Meeting shall not be conducted without Purchaser’s representative.
3. Supplier shall be responsible for preparation of minutes for the previous day’s meeting and
shall submit the minutes at the start of each day’s meeting.
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5.2
SSM-SU-5297.1
Worksite Progress Meetings
1. Supplier and Purchaser shall attend worksite progress meeting at a time and location
acceptable to both parties.
2. Meeting shall cover the following:
a. Safety concerns such as accidents, near misses, inspections, and management audits.
b. Progress to-date, including work hours expended, comparison of actual progress against
plan, and planned operations for the upcoming week.
c. All other issues related to onsite progress.
5.3
Pre-Construction Meeting
1. A pre-construction meeting shall be held with Purchaser for each aspect of the project
(i.e., fabrication and installation) at least 30 days before construction operations.
2. At this meeting, Supplier shall present detailed construction procedures.
5.4
Kick-Off Safety Meetings
1. No later than one week before the earliest day of mobilization for the onsite work
commencement, Supplier shall hold a project safety meeting that shall be attended by at least
the following personnel:
a. Project manager.
b. Project engineer(s).
c. Construction vessel captain (if available).
d. Construction superintendent.
e. Other vessel captain(s).
f.
Deck foremen.
g. HES personnel.
h. Purchaser representatives.
i.
All other relevant personnel.
2. Before the project safety meeting, an agenda shall be issued by Supplier that includes, as a
minimum, the following:
a. Review outstanding action item checklist from Supplier’s vessel/equipment verification
inspection.
b. Review Supplier’s proposed work procedures with emphasis on safety, efficiency, and
quality assurance.
c. Discuss and address safety concerns pertinent to this project (including lessons learned
from previous projects).
d. Present and discuss emergency procedures and response scenarios for accidents and
deteriorating weather conditions.
e. Review mobilization and work schedules, and analyze conflict considerations such as
third-party work and weather impacts.
f.
Status of completion of Purchaser-mandated safety trainings and requirements.
3. Supplier may split the work scope for discussion into more than one meeting.
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5.5
SSM-SU-5297.1
Purchaser Meetings
As required by Purchaser, Supplier shall participate in Purchaser-sponsored meetings such as
the following:
1. Constructability reviews
2. Value improvement practice (VIP) discussion
3. Hazard identification (HAZID)
4. Hazardous operations (HAZOP)
5. Risk assessments
6. Incident and injury free (IIF) or incident free operations (IFO)
7. Cost and schedule risk assessments
6.0
DOCUMENTATION
1. Supplier shall prepare and submit as required the supporting documentation shown in Table 1.
2. All Supplier documentation shall be provided in both hard copy and electronic formats.
Table 1:
Supplier Data Requirements Matrix
Document
Due Date
Material control procedure
60 days after contract award
Transportation plan(s)
60 days after contract award
Installation vessel specifications
30 days after contract award
Diving log books
Daily
Weather reports
Daily
Current profiles
Daily
Management of change (MOC) procedure
30 days after contract award
Inspection matrix
30 days before start of activity
Installation trial procedures
60 days before mobilization for sea trials
Installation manual
60 days before mobilization
Monthly reports
Continuous each month after contract award
Tally record of pipe joint
Continuous during installation
Daily report
Continuous during installation
Diving procedures
Activity before any diving
Installation trials data book
30 days after completion of trials
As-built documentation
30 days after installation
As-built survey drawings
30 days after installation
Installation static and dynamic analyses for pipelay,
A&R, initiation, structure installation, riser hang-off,
and laydown
60 days before mobilization
Offshore QACP documentation
Daily during installation
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6.1
SSM-SU-5297.1
Submittals with Bid
1. Supplier shall submit a detailed project schedule with the bid (CPM or bar chart). Schedule
shall outline the total days to complete the project and sub-detailing the duration for each of
the following activities:
a. Project planning
b. Weld procedure qualifications
c. Welder qualifications
d. Pipeline welding
e. Riser welding
f.
Weld procedure matrix
2. Information shall be included in the project schedule concerning Supplier’s expected work
load (i.e., other projects that would compete with project for resources, personnel, and space).
3. Supplier shall provide a detailed work plan describing how the project would be completed.
a. Work plan shall include information on the receipt of material, the flow of material, and
a manpower summary.
b. In addition, Supplier shall describe how they would handle (if possible) an accelerated
schedule (e.g., working 24 hours).
4. Supplier shall provide a detailed work plan associated with the fabrication and setup of a joint
fabrication facility. This document shall include the following:
a. Detailed schedule of the facilities fabrication and setup.
b. Capabilities of the facilities (i.e., joint lengths and weight limits).
c. Process flowchart.
d. Detailed work plan explaining the process of how Supplier anticipates joints being
fabricated.
5. In addition, an overall layout of the facilities detailing representative material flow throughout
the facilities shall be provided. Layout shall include at least the following:
a. All dimensions.
b. Material storage capacity.
c. Water access details including water depth.
d. Accessible barge size (dimensions and weight load).
e. Covered work space dimensions.
f.
6.2
Covered storage dimensions.
Submittals Before Pipe Assembly
Supplier shall submit the following documents and procedures to the Purchaser 60 days before
commencing pipe assembly operations for review and acceptance:
1. Pipe assembly procedures and equipment.
2. Material and fabrication processes and procedures of the pipe assembly components.
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3. Quality plan and quality assurance and control (QACP) procedures.
4. Handling, storage, and transportation procedures.
6.3
Submittals Before Starting Operations at Site
1. Supplier shall prepare proposed installation procedures and schedule from contract award
through job completion. Specifications, drawings, calculations, and descriptions made by
Supplier during the tender submission stage shall be included to show sufficient detail to
demonstrate pipeline installation system feasibility.
2. The following shall start only after written Purchaser acceptance:
a. Mobilization of installation vessel and equipment.
b. Work on the installation vessel.
3. Installation procedures shall cover all phases of loadout, transportation, laying, burial,
trenching, crossings, and testing of the pipeline system, including pipeline and risers. These
procedures shall be submitted in the form of one or more written reports (including a pipeline
installation manual complete with drawings and calculations), at least three weeks before the
pre-installation meeting.
4. Supplier shall not proceed with installation operations until the Purchaser has reviewed and
accepted the installation procedures in writing.
5. Supplier shall include a project personnel chart proposing construction personnel and their
areas of responsibility, and a project schedule showing work to be done by each marine vessel.
6. Supporting data included in the reports shall be sufficient to show compliance with the codes,
standards, recommended practices, and technical requirements.
a. Supporting data in the reports shall include applicable industry standards and codes not
specified herein, but that are necessary to prove the validity of Supplier’s proposed
specifications and installation and testing procedures.
b. When computer output is provided, Supplier shall furnish a description of the analytical
methods and parameters employed in the program, and shall identify the basic theory
used.
7. Pipelaying procedures for beginning and ending pipelaying activities and for installation of
risers shall be prepared by Supplier during the design phase, and included in the pipeline
installation manual.
a. Pipelaying procedures shall be reviewed before and during the pre-installation meeting,
and before the beginning of pipelaying activities.
b. Procedures shall be accepted in writing by Purchaser.
6.4
Installation Manual
1. A minimum of 60 days before the scheduled start of mobilization for installation, Supplier
shall submit for Purchaser review and acceptance an installation manual, both in hard copy
and electronically on CD. At a minimum, the installation manual shall include the following:
a. HES procedures for all phases of work, as detailed by Purchaser-specific documentation
herein.
b. Simultaneous operations procedures (hierarchy).
c. List of onshore fabrication activities.
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d. Onshore fabrication procedures.
e. Welding procedures, welding procedure qualification (WPQ), welding qualification and
testing (WQT).
f.
Nondestructive testing (NDT) procedures.
g. Installation analysis for all aspects, including, but not necessarily limited to, normal
pipelay, pipelay in maximum and minimum water depths (WDs), abandonment, recovery,
vessel excursion, spool pieces installation, and risers recovery and hang-off.
h. Pipelay procedures.
i.
Pipelay tables (including A&R) for multiple WDs, provided in a format that is usable by
the vessel.
1) The information monitored on the vessel shall be included in the table for reference
(i.e., layback touchdown distance, tensions, etc.).
2) Tables shall be in a format that allows installation Superintendent to use them without
modifications.
3) A sketch shall be included with pipelay tables that clearly defines the variables and
terms.
j.
Abandonment and recovery procedures.
k. Emergency flooding and de-watering procedures.
l.
Repair procedures.
m. Filling procedures.
n. Survey and positioning procedures (including equipment list and capabilities).
o. Installation vessel specifications.
p. Subsea inspection procedure.
q. Diving and ROV operations procedures.
r.
Field joint coating procedures.
s.
Coating inspection and repair procedures.
t.
Pipeline pickup, laydown, and repositioning procedures.
u. Tension monitoring procedures.
v. Subsea inspection procedures.
w. ROV equipment and spares.
x. Spans detection and rectification procedures.
y. Vessel emergency response plan.
z. Contingency procedures for potential occurrences such as unauthorized discharges,
accidents, medical emergencies, and equipment failures.
aa. Weather condition monitoring procedures.
ab. Communication system specifications.
ac. Subsea structure installation procedures.
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ad. Anode attachment.
ae. Trenching and burial detail.
af. Tow-in arrangement (for towed pipelines).
2. Procedures shall cover the full WD range of the project.
3. Each procedure shall be supported by detailed calculations that are sufficient to show
compliance with the relevant codes, standards, and specifications.
a. For calculations provided in the form of computer output, Supplier shall furnish
descriptions of the output and computer programs.
b. The basis for the calculations and any assumptions used shall be identified.
4. Supplier shall provide and maintain a detailed project schedule that includes all aspects of
the project.
5. Purchaser acceptance of Supplier installation methods and procedures shall not relieve
Supplier of responsibility as detailed in the contract for the safe and efficient installation of the
pipelines, risers, subsea structures (PLETs and in-line sleds), and appurtenances to the
satisfaction of Purchaser. Supplier shall obtain Purchaser written acceptance for any deviations
from the agreed-upon procedures.
6. Supplier shall provide a management plan for Purchaser review and acceptance.
7.0
QUALITY ASSURANCE AND CONTROL
1. Supplier shall have a functioning quality assurance and control program (QACP) and standard
operating procedures that control application, inspection, and testing during the assembly
process.
2. Supplier shall submit QACP to Purchaser for review and acceptance.
a. Purchaser shall determine the level of activities to witness or review.
b. Supplier shall ensure that all Sub-Suppliers maintain equivalent QACP and inspection
systems.
3. QACP shall be the responsibility of Supplier, who shall ensure compliance with all specified
requirements and good workmanship practices.
4. QACP procedures shall include, but not be limited to, the following:
a. Organization chart to be used on this contract.
b. Flowchart identifying checklist activities for pipe assembly control and acceptance points.
c. Material control, including procurement, receipt, marking, storage, handling, and use of
material.
d. Inspection and handling control procedures, including control points.
e. Quality status marking and control system.
f.
Stock material traceability and dating system.
5. Purchaser may perform audits of Supplier’s QACP system, and shall be permitted access by
Supplier to all assembly, field joint application, anode installation, and inspection areas at any
time work is being performed for Purchaser.
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6. All fabrication work shall be documented.
a. All weld cut-outs, pipe cuts, and field joint coatings shall be documented.
b. Documentation shall include both Supplier and Purchaser representatives’ signatures.
8.0
MATERIAL
8.1
Material Provided by Purchaser
1. Supplier shall be responsible for Purchaser-supplied material receipt, handling, sorting,
storage, and load-out of all material on offshore installation Supplier-provided
transportation.
2. For Purchaser-supplied items, it shall be the responsibility of the Supplier representative to
ensure that material received matches items purchased from manufacturer. Purchaser’s
representative shall be provided with a description of material ordered to assist the inspection
of incoming material.
3. Supplier and Purchaser’s representative shall check quantity and condition of any material
supplied by Purchaser on receipt by Supplier at the staging area or designated delivery point.
a. Supplier shall be responsible for any subsequent loss or damage.
b. Supplier shall provide written acceptance of Purchaser-supplied material within two
working days.
c. Supplier shall provide all other material necessary to complete the fabrication and
installation.
4. Supplier shall maintain records to properly document the receipt, issue, return, and disposal of
all material supplied by Purchaser, and shall permit inspection of the records by Purchaser at
all reasonable times. In particular, the records shall reference identification and serial numbers
indicated on the materials.
5. All damage, flaws, and other defects to material shall be identified and recorded by Supplier
upon receipt. Supplier shall provide written documentation (i.e., non-conformance report
[NCR] on this issue) to Purchaser. Purchaser reserves the right to review the extent and type of
damage, flaw, or other defect identified by Supplier.
a. Damage shall, where possible, be remedied by Supplier.
b. Defective material that cannot, in the opinion of Purchaser, be repaired by Supplier, shall
be removed and stored separately by Purchaser.
6. Material furnished to and accepted by Supplier shall be deemed to be in the custody of
Supplier from time of receipt until used in the work.
a. Materials damaged while in Supplier’s custody shall be replaced by Supplier.
b. Supplier shall be responsible for returning unused material to Purchaser.
8.2
Material Provided by Supplier
1. Supplier shall provide all materials for the work that are not listed as free issue to Supplier by
Purchaser.
a. If Supplier is required to supply material as part of the permanent scope, there shall be
additional requirements by Purchaser.
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b. Supplier shall provide mill certificates for all pipe, flanges, and fittings supplied by
Supplier.
c. Supplier shall be responsible for the transportation of all material.
2. Supplier shall maintain material take-offs and measurements to determine the quantities of
material to be supplied. Due allowance shall be made for any contingencies and other events.
3. Material to be provided by Supplier for use in the work scope shall be new, of good quality,
without defect, and shall have relevant certification documents to show conformance with
specifications. Material not conforming to the specification or otherwise rejected by Purchaser
shall be removed from the work site by Supplier, and replaced with acceptable material at the
sole expense of Supplier.
4. When doubt exists regarding the identity of material in the work scope, or the conformance of
a weld with the accepted procedure, at Purchaser’s request Supplier shall cut out and remove
for testing any section of the questioned material or welded area.
a. Subsequently, if satisfactory test results are obtained, Supplier shall restore the material or
area following Purchaser-accepted procedures at no additional cost.
b. Testing shall be to Purchaser, verification agency, and warranty surveyor requirements.
c. If the weld is a good weld, Purchaser shall pay, and if the weld is bad (i.e., does not meet
the weld defect acceptance criteria), Supplier shall make good at its cost.
5. Supplier shall fully document strength testing of any Supplier-provided material that is
pressure containing.
6. Fabricated items and component material shall be appropriately labeled and stored in
conditions that are not detrimental either to their base material or their applied coatings.
7. Only new material shall be used. Stocks of material whose shelf life has expired shall not be
used.
8. Material selected shall be suitable for long-term exposure to seawater and expected
temperatures, pressures, weather, salt air, and humidity.
9. Each consignment of material shall be checked to conform to the QACP procedures.
9.0
ACCEPTANCE, STORAGE, AND TRANSPORT OF MATERIAL
9.1
Material Control Procedure
1. Supplier shall submit the material control procedure for Purchaser review and acceptance
60 days after award of the contract. At a minimum, material control procedure shall include
the following:
a. Procedure for loading and unloading pipe and equipment.
b. Description and specifications for equipment to be used.
c. Description and specifications for modes of transportation.
d. Procedure for control of damaged project material.
e. A logistics plan on how the material will be managed while onsite, coming, and going.
2. In addition to the information in item 1 above, the material control procedure shall include the
relevant calculations required to ensure safe transportation and handling of materials, as
shown in Table 2.
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Table 2:
9.2
SSM-SU-5297.1
Calculations Required for Safe Transportation and Handling of Materials
Calculation
Description
Line Pipe Stack Height
Calculations
Supplier shall provide calculations and drawings for proposed stacking
heights and support system, showing that static load stress does not
exceed the limits established in API RP 5LW, and coatings are not loaded
beyond the allowable stress stated in the insulation/coating design report
(prepared by insulation/coating Supplier).
Allowable Stress
During Lifting of Pipe
Supplier shall provide calculations for lifting pipe joints to confirm that
maximum combined (axial plus bending) strain of 0.1 percent is not
exceeded. A dynamic load factor of 1.50 shall be considered when
calculating stress. For lifting from a pipe transportation barge to the
installation vessel, the dynamic load factor shall be 2.0.
Lift Analysis for Lifts
Greater Than Five
Tons or Critical Items
Supplier shall provide lifting calculations and drawings, including rigging
drawing, for all loads greater than five tons or critical in nature. These
calculations shall include determination of center of gravity and sling loads,
sling and shackle specifications, lifting eye checks, and crane ratings.
Storage
1. Supplier shall be responsible for all pipe, material, or both, from when they are delivered to
Supplier’s yard until final load-out.
a. Supplier shall be able to store completed single or multi-joints for convenient load-out into
storage bins or onto material barges.
b. Single or multi-joints shall be completed at least 60 days before their installation.
2. Supplier shall provide a secured staging area with 24-hour surveillance for Purchaser-supplied
material from before mobilization until job completion.
3. All project material shall be stored under conditions that do not detrimentally affect
performance characteristics. At a minimum, the following shall be adhered to:
a. Pipe shall be stacked and protected to prevent damage to pipe and coatings.
b. Protruded bracelet anodes joints shall be stacked at the top layer.
c. Storage areas shall be well drained and free from material likely to cause physical or
chemical damage to pipe or coatings.
d. Pipe racks shall be of sufficient height to prevent pipe surface or uncoated ends of coated
pipe from touching the ground, or allowing ground runoff water to enter pipe.
e. Pipes shall be stockpiled on a horizontal surface in a pyramidal shape or between rows of
sufficiently spaced stanchions. Wood or other soft dunnage with plastic covers shall be
used to support the bottom layer and to eliminate contact of the pipe with metallic surfaces
or soil.
f.
Pipe ends shall be protected at all times.
g. Special arrangements shall be made for storage of items that are weather sensitive
(e.g., rain, temperature, sunlight).
h. Pipe shall be angled so that water drains out if it rains or floods.
i.
All insulation material shall be stored and installed in clean dry conditions that comply
with insulation manufacturer recommendations.
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4. Supplier shall submit for Purchaser review and acceptance a storage plan for single or multi
joints with stacking details. Maximum stacked height shall be proposed by Supplier, and
calculations provided to justify proposed stacking height.
a. The bottom layer of pipe shall be adequately supported on sand berms or timbers to
prevent constant contact with standing water.
b. Fatigue-sensitive riser joints shall not be nested.
c. Multiple joint layers shall be separated by an adequate number of appropriately sized
timber stripping (i.e., 4 × 4-inch [100 × 100-mm] timbers), and the total number of layers
shall not exceed 6 unless accepted by Purchaser.
9.3
Receipt of Line Pipe
1. Purchaser shall not accept responsibility for any defect if it is not immediately identified upon
receipt by representatives of Supplier and Purchaser.
2. Upon receipt of the line pipe and during offloading, Supplier shall stockpile pipes into suitable
ranges of pipe joint length to assist retrieval of desired lengths.
3. Pipe joints shall be numbered and the following items, as a minimum, shall be recorded on a
tally sheet, pipe tracking software, or both:
a. Pipe manufacturer’s unique joint number.
b. Heat number.
c. Purchase order number.
d. Most recent measured length.
e. Date received.
f.
Pipe diameter and wall thickness.
g. Material grade.
h. Damage to the pipe.
i.
Identification by SCR, fatigue sensitive pipeline, and normal pipeline.
4. Supplier shall accept receipt of all line pipes when the pipe joint is released from the hook onto
Supplier’s means of transport at Purchaser-designated location.
a. Pipe shall be loaded on the Supplier’s transportation.
b. Supplier shall be responsible to secure line pipe and material onto transportation.
5. Supplier shall witness loadout tally and sign for receipt of all pipe at that time.
a. Supplier shall inspect pipes for damage (e.g., steel damage or coating damage) at the time
of loadout, and any damage observed shall be noted on the loadout tally.
b. At Supplier’s option, pipe may be re-measured by Supplier to verify footage, but a
Purchaser representative shall witness all measurements.
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9.4
SSM-SU-5297.1
Receipt of Purchaser-Supplied Material
1. Supplier shall receive, check, visually inspect, and accept free-issue items and supporting
documentation.
a. Supplier shall notify Purchaser of discrepancies or damage to the free-issue items within
24 hours of receipt.
b. In the absence of such notification, free-issue items shall be deemed to have been
delivered in a complete and undamaged state, and any discrepancy or damage that could
reasonably have been discovered by Supplier, or by any testing and inspection specified
elsewhere in the contract, shall be the responsibility of Supplier.
c. Supplier shall be responsible for delays or rescheduling attributable to repairing or
replacing such free-issue items.
2. Purchaser representative shall be present at all times during the unloading of Purchaser
supplied material.
3. Supplier shall maintain, in a form agreed by Purchaser, adequate records for free-issue items,
and shall provide a regular weekly inventory to Purchaser to show the use of items received
and the balance of material unused. Supplier shall identify location(s) where pipe and other
materials are stored.
4. Supplier shall provide suitable and safe storage for free-issue items, and shall make good any
loss, damage, or deterioration that may occur to them while in the possession or control of
Supplier.
a. Supplier shall be solely responsible for the material after receipt, and pipe or material lost,
stolen, or damaged while in possession of Supplier shall be charged to or replaced by
Supplier.
b. Supplier shall ensure that before incorporation into the work scope, the free-issue items
carry clear identification that they belong to Purchaser.
5. Supplier shall clarify special delivery instructions in writing, including, for example, the
following:
a. Required notice before delivery (i.e., 24 hours).
b. Delivery hours (i.e., 7:00 am to 5:00 pm).
c. Delivery days (i.e., Monday–Friday).
d. Shipping/receiving coordinator’s information (i.e., phone, fax, and email).
6. Supplier shipping/receiving coordinator shall be responsible for reporting the arrival and
off-loading of material to Purchaser representative. Supplier shall provide as a minimum the
following information:
a. Date of delivery.
b. Item description (include dimensions and grade).
c. Quantity.
d. Purchase order no. (if applicable).
e. Sub-Supplier name.
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9.5
SSM-SU-5297.1
Handling
1. Pipe damaged during handling, storage, or transportation shall be identified, and disposition
shall be obtained from Purchaser. Supplier shall provide detailed NCR so the issue and
resolution are documented.
2. Supplier shall handle the pipe and other free-issue material so as not to damage the pipe,
material, or coatings. Handling shall meet the requirements of API RP 5LW.
3. To prevent damage during handling of pipe, all possible precautions shall be taken, including
the following:
a. Pipe shall not be dropped.
b. Pipe shall not be rolled on a surface that can damage pipe or coating.
c. Pipe shall not be stored or handled in such a manner as to distort the round form of the
ends or damage the bevels.
d. Other than specially accepted lifting tools, only wide non-abrasive canvas or leather belts
shall be used to prevent damage to pipes and components.
e. Acceptable end hooks may also be used for handling pipe.
1) When end hooks are used, they shall be designed to prevent damage to pipe ends.
2) They shall have sufficient width and depth to fit the pipe inside diameter.
f.
Use of tongs, bar pinch bars, chain or rope slings without canvas covers, slings with
protruding rivets, pipe hooks without proper padding, or any other handling equipment
found to be injurious to the coating shall not be permitted.
g. Joints and sections of coated and wrapped pipe shall be picked up clear of the ground and
not dragged over the ground. In the handling of coated pipe, impact shall be minimized,
and skids used to support coated pipe shall be adequately padded.
h. Insulated or corrosion-coated pipe shall be handled with special care to avoid damage.
i.
Supplier shall verify that handling equipment and stacking design does not damage or
compress the insulation.
j.
Handling shall be carried out in such a manner that impact loads sufficient to cause local
denting or out-of-roundness of pipe body or pipe ends does not occur.
k. Pipes shall be picked up clear of the ground or deck of the barge and moved bodily, not
dragged over the ground or the barge deck. Pipe shall not be subjected to jars or impacts.
l.
Skids used to support coated line pipe shall be of sufficient width so as not to damage the
coating.
m. Coated and uncoated pipe shall not be subject to jars or impacts, but shall be lifted or
lowered from one level to another by suitable equipment.
1) Only special lifting hooks acceptable to Purchaser and equipped with a plate curved to
fit the curvature of the inside of the pipe shall be used.
2) In loading pipe on trucks, rail cars, and barges, each length shall be lowered to
position without dropping, and each succeeding length shall rest evenly with other
lengths.
3) For pipe loaded on trucks, suitable chains with padding shall be used to tie the load
securely to each bolster.
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n. Bolsters of trucks, rail cars, and barges used for coated pipe transportation shall have a
bearing surface of not less than 12 inches (300 mm), to give necessary support to the
padding that protects the coating.
1) Sacks partially filled with sand or sawdust shall be placed on the bolsters and between
the outside bottom pipes and bolster stakes.
2) In general, maximum piling height on trucks, rail cars, and barges shall be limited to
the maximum height recommended by the coating manufacturer, and chains, cable,
and other equipment used for fastening the load shall be carefully padded to prevent
damage to the coating.
4. Purchaser shall have the right to inspect pipe handling. If, in the opinion of Purchaser, pipe is
being handled improperly or proper precautions are not being taken, the handling of the pipe
shall stop until the problem is corrected.
5. Racks (e.g., storage and welding) shall be fabricated to support the weight of insulation coated
pipe without damaging the insulation. Supplier shall provide written documentation that
demonstrates this requirement.
6. Supplier shall handle and store flanges and connectors, fittings, valves, insulating flanges, and
other material in a manner to preserve their condition, prevent loss, and protect against
damage and theft.
a. Flanges and connectors, fittings, valves and hubs, insulating flanges, and other material
with finished surfaces shall be elevated to prevent contact with the ground or other
corrosive surfaces.
b. Valves and hubs and flanges and connectors shall be stored with temporary closures over
the ends.
7. Supplier shall pack, handle, and store prefabricated assemblies such as pipeline sleds or
side-tap assemblies in a manner to prevent damage to the assembly and other material.
9.6
Transportation
1. Supplier shall be responsible for transportation of Purchaser free-issue material. Unless
otherwise specified by Purchaser, transportation shall meet the requirements of API RP 5L1
or API RP 5LW, as applicable.
2. Chains, cables, strapping, stanchions, and other material and equipment used for fastening and
tying down the pipe for transportation purposes shall be carefully padded.
a. Dunnage, skids, or padding shall be used to protect the bottom layer of pipe from the barge
deck.
b. Seafastening, including procedures for the line pipe, shall be reviewed and accepted by
Purchaser.
3. The restrictions on stacking in Sections 8.1 and 8.2 shall apply.
4. Valves, fittings, and other loose material (except pipe) shall be transported offshore on supply
boats or other suitable vessels. Only pipe shall be transported on pipe haul barges.
5. Supplier shall secure the required material handling permits and shall perform barging,
hauling, and trucking in accordance with the appropriate laws and regulations of governmental
agencies, other controlling authorities, or both.
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6. Supplier shall prepare plans and procedures for loading, hauling, unloading, storing, and
handling pipe. Plans and procedures shall be submitted to and accepted by Purchaser before
Supplier commences work.
7. Supplier shall load out single and multiple joints onto Supplier-provided barge-mounted
storage bins or onto material barges.
a. Once selected, offshore installation Supplier shall provide bin drawings indicating the
location of particular single and multiple joints (e.g., bulkhead joints) that are required for
the load out and installation sequence. Supplier shall group the loadout and staking per the
coating type of the pipe joints.
b. Supplier shall provide a loadout plan for single and multiple joints.
c. Supplier shall have waterfront property with direct access to open water suitable for
navigation with typical material barges. Supplier shall address (in the bid) ability to handle
material barges, and what effort would be required to make this possible.
d. No persons shall assist in the load out of single or multiple joints unless they have the
necessary experience and qualifications (i.e., a riggers certificate).
9.7
Material Traceability
1. Components, materials, and welds shall be clearly marked in accordance with Supplier’s
procedure for identification. Procedure for identification shall define in detail the following:
a. How Supplier will control the identification and marking of material and welds.
b. How Supplier will record weld history nondestructive examination (NDE) results and
material placement.
2. Full traceability shall be required for pipe and material components of the permanent pipeline
system. Material assemblies and sub-assemblies, including weld identities, shall be recorded.
3. For material not required to be fully traceable, Supplier shall ensure by the adoption of a
suitable marking system acceptable to Purchaser, that only specified and certified material are
built into the work.
4. Material not bearing the appropriate material identification marking shall not be built into
the work.
9.8
Cleanup, Pollution Control, and Damages
1. At the completion of the project, Supplier shall provide the handling and transportation
necessary to relocate surplus material to a location designated by Purchaser.
2. Supplier shall provide personnel and equipment necessary to accomplish the following:
a. Disassemble spare fabricated pipe sections into the as-received condition.
b. Load out scrap material, as directed by Purchaser.
3. Salvaged, excess, and waste material shall be disposed of in a manner satisfactory to
Purchaser.
4. During installation, Supplier shall not discard any construction material, scrap, auxiliary
installation equipment, or other objects on the seabed.
5. Temporary installation equipment, anchors, and buoys shall have locations defined during
installation process so they can be easily located and removed at close of project.
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6. Vessels under contract to Purchaser shall strictly control the disposal of material on the vessel
from previous work or used during construction.
7. The negligent throwing of trash (e.g., cans, bottles, rope, cable, welding rods, brushes, cups,
and paper) overboard shall give the Purchaser representative authority to ask for that person’s
removal from the vessel.
a. Supplier shall have adequate trash barrels on the vessel to promote proper trash disposal.
b. If requested by Purchaser representative, Supplier shall provide additional trash barrels.
8. If debris is accidentally placed on the seabed, it shall be recovered by Supplier at Supplier
expense.
9. Temporary work sites, storage yards, and sites on land, if established solely for this project,
shall be cleaned up and the sites returned to their original condition. Any temporary
obstructions or construction aids placed along the pipeline route or along the pipeline
right-of-way shall be removed at Supplier’s expense, unless Purchaser specifically requests
that they be left in place.
10. Supplier shall remove surplus material from the work site and shall deliver such material
belonging to Purchaser to Supplier’s staging area.
a. Supplier shall load out such material onto Purchaser-furnished transportation at no extra
charge.
b. Salvaged, excess, and waste material shall be disposed of in a manner satisfactory to
Purchaser.
11. At the completion of the project, Supplier shall provide handling and transportation necessary
to relocate all surplus material to a location designated by Purchaser.
12. Supplier shall provide necessary personnel and equipment for the following:
a. Disassembly of spare fabricated pipe sections into the as-received condition.
b. Load out of all scrap material.
10.0
PIPE JOINT FABRICATION
1. Joints shall be fabricated in accordance with this specification and Purchaser-supplied
drawings.
2. Supplier shall prepare a design assembly and inspection procedure.
3. Supplier shall provide an assembly and test site to perform pipe makeup.
4. Pipe shall be coated with Purchaser-accepted insulation or coating specification.
5. Fabrication of joint length shall meet the requirements of offshore Supplier equipment and
methodology.
6. Supplier shall provide a detailed design of fatigue-sensitive pipe sections. Design shall
account for the required fit-up tolerances defined by the project.
a. This design shall be done initially for pipe in the as-received condition, and shall not
include end-machined ends.
b. If Supplier can demonstrate that the fatigue-sensitive sections cannot be assembled
without end machining, Supplier shall submit an end machining plan for Purchaser
acceptance before beginning any construction.
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7. Equipment used for the assembly of the pipe shall be of proven design and in good operating
condition.
8. Methods employed shall be in accordance with prudent engineering, fabrication, and
construction practice.
10.1
Multiple Joints
1. Onshore fabrication of multiple joints (i.e., double, quad, or hex joints) shall include the
following:
a. Unloading pipes from barges and sorting the pipe by length, as necessary.
b. Transporting and handling of pipes throughout fabrication process.
c. Fabricating single joints (approximately 40 feet [12.2 m]) into double joints
(approximately 80 feet [24.4 m]), including welding and inspection.
d. Fabricating fabricated double joints (approximately 80 feet [24.4 m]) into quad joints
(approximately 160 feet [48.8 m]), or fabricated three double joints into hex joints
(approximately 240 feet [73.2 m]) including, but not limited to, welding and inspection.
e. Incorporating J-lay collars into a predetermined number of the double and quad joints as
necessary (details to be provided by Installation Supplier) or Supplier-fabricated friction
clamps into a predetermined number of the double joints as necessary (accepted design
and details to be provided by Installation Supplier).
f.
Installing a complete field joint including insulation on double, quad, or hex joint weld.
g. Installing corrosion coating on collars (if applicable) onto a predetermined number of
multi joints as necessary.
h. Loading out fabricated double, quad, or hex joints onto installation Supplier’s
transportation.
i.
Incorporating loading out fabricated hex joints onto installation Supplier’s transportation.
2. Supplier shall identify any variances from item 1 list above to ensure that there is a complete
understanding and agreement regarding what is required to complete the onshore fabrication.
10.2
Stalks and Half Stalks
1. Stalks and half stalks shall be required in the event that the pipeline and riser system is
installed by the reel lay method.
a. Stalks and half stalks joints shall be fabricated in accordance with this specification and
installation Supplier-supplied drawings.
b. Detailed installation Supplier drawings shall be reviewed and accepted by Purchaser
before fabrication.
2. Onshore fabrication of stalks and half stalks shall include at least the following:
a. Unloading of Purchaser-supplied pipe from barges and sorting of the pipe by length as
necessary.
b. Transporting and handling of Purchaser-supplied pipe throughout the fabrication process.
c. Fabricating stalks and half stalks from Purchaser-supplied pipe joints. Fabrication shall
also include welding and inspection.
d. Installing complete field joint, including insulation, on all stalk and half stalk welds.
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10.3
SSM-SU-5297.1
Tie-In Spools (Between SCR and Host Platform)
1. Tie-in spools shall be required for connection of the risers to the platform hull piping.
a. Exact configuration of the riser tie-in spools shall be made available after the host
platform and riser approach configuration are selected.
b. Tie-in spools shall be fabricated in accordance with this specification and Purchaser
supplied and accepted drawings.
2. Onshore fabrication of tie-in spools shall include at least the following:
a. Unloading of pipe and material from barges and trucks, and sorting material as necessary.
b. Transporting and handling of material throughout the fabrication process.
c. Fabricating tie-in spools that are based on precise measurements from the selected
platform (includes welding and inspection).
d. Hydrotest, if necessary.
e. Installing complete field joint (including insulation if applicable) on all tie-in welds.
10.4
Subsea Tie-In Spools
1. Subsea tie-in spools shall be required for the connection of the riser to the platform.
a. Exact configuration of the subsea tie-in spools shall be made based on pre-test fitting or
Purchaser-accepted survey methodology.
b. Subsea tie-in spools shall be fabricated in accordance with this specification and Purchaser
supplied and accepted drawings, or Supplier-accepted shop drawings.
c. Purchaser or Supplier shall provide the spool configuration as soon as it is available,
depending on the contract scope.
2. Onshore fabrication of tie-in spools shall be required, except for the green or field-adjustable
length and green or field-adjustable bends.
3. Onshore fabrication shall include, but not be limited to, the following:
a. Unloading of Purchaser or Supplier-provided pipe and material from barges and trucks,
and sorting material as necessary.
b. Transporting and handling of Purchaser or Supplier-provided material throughout the
fabrication process.
c. Fabricating partial subsea tie-in spools based on precise measurements from the selected
platform (includes welding and inspection).
d. Hydrotest, if necessary.
e. Installing complete field joint (including insulation if applicable) on all tie-in welds.
4. Supplier shall perform survey to determine the required tie-in spools lengths and bends.
5. Supplier shall identify variances from the lists in items 1 and 4 above to ensure that there is a
complete understanding and agreement regarding what is required to complete the onshore
fabrication.
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SSM-SU-5297.1
Additional Pipe Identification after Fabrication
1. Identification in addition to those listed in Section 9.3 shall be required on each fabricated
joint of pipe. The following shall be documented and the items recorded:
a. Weld numbers.
b. NDE numbers.
c. Coating or insulation type, date of application, and thickness.
d. Coating damage.
2. For each assembled joint requiring a cut-out, an individual report shall be generated that
provides the following information:
a. Cut-out length.
b. Measured length (as-built).
c. Reason for cut-out.
d. Reference magnetic particle inspection (MPI) report numbers.
e. Date and time of cut-out.
f.
Personnel responsible for cut-out.
g. Supplier name and signature.
h. Purchaser name and signature.
11.0
PIPELAY EQUIPMENT AND REQUIRED PERSONNEL
1. Supplier shall provide a description of pipelay personnel and equipment.
2. Personnel shall be adequately trained, qualified for the tasks to be undertaken, experienced in
these tasks, shall have completed competency validation, and shall maintain up-to-date
qualifications.
11.1
Installation Spread
1. Supplier shall issue to Purchaser as part of the pipeline installation manual a complete pipeline
installation spread with the following characteristics:
a. Capable of working in the WDs, bottom conditions, and environmental conditions
encountered along the route.
b. Suited to safely install the pipelines and associated appurtenances.
2. Installation vessel information shall describe the following laying equipment:
a. Description of the vessel dimensions, classification, dynamic positioning (DP),
accommodations, speed, deck equipment, deck storage space, fuel capacity, water
capacity, communications, and all other attributes that make the vessel appropriate for
the work.
b. Details of any modifications of the installation vessel to accommodate the installation
requirements of this project.
c. Details of pipe monitoring system (i.e., systems that are used to ensure pipe stays within
allowable limits).
d. Barge laying configuration, including stinger hitch and ramp roller heights.
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e. Stinger type, radius, depth, ballast control, instrumentation, and monitoring.
f.
Tensioner specification and drawings.
g. Work stations and locations description.
h. Drawings showing the support rollers and the pipeline profile geometry.
i.
Deck plan on the lay barge and other vessels in the spread.
j.
Surface and subsea positioning systems description.
k. Positioning and pipelay monitoring equipment description.
l.
Pipe holdback equipment and internal line-up clamp drawings.
m. A&R winch specification.
n. Davits (if required).
o. Welding and field joint coating facilities.
p. Mooring and anchoring equipment.
q. Weld inspection system.
r.
ROV and dive support equipment.
s.
Personnel transport capabilities, e.g., basket or helipad.
t.
Lifting cranes.
u. Other equipment required and present for the installation of the pipeline.
3. Supplier’s installation spread shall be in a good and serviceable condition and shall be
maintained in this condition during work. Supplier shall maintain and keep in full force and
effect permits, certificates, and licenses required to use the vessel(s) and crew to perform
work. The certifications shall include as a minimum the following:
a. Certification that Supplier’s vessels may transport material to site, work in the appropriate
country’s waters, enter the project country’s ports in the area near the project, and may
verify that the vessels are in compliance with relevant regulations of the project country.
b. Certification that the vessels have been specifically inspected by the proper regulatory
authority of the appropriate country (e.g., Coast Guard for the U.S.A.).
c. Copies of the most recent certifications or test results from pipelay-related equipment
including winches, hydraulics clamps, and tensioners.
4. Supplier shall make required input data such as lay vessel response amplitude operators
(RAOs) and vessel configurations available to Purchaser or designated representative, because
Purchaser may elect to perform analyses similar to those performed by Supplier.
a. Results of the analyses shall be compared as a check on the work of both parties.
b. A joint effort shall be made to determine the reason for any significant differences.
c. Differences shall be resolved before the installation procedures are finalized.
5. Supplier shall provide detailed stinger configurations to allow for independent verification of
the installation analysis.
6. Lay ramp shall be equipped with camera(s) to permit visual monitoring of the pipeline as it
passes over the end of the lay ramp.
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7. Pipe support heights and positions shall be related to some clear and easily definable datum.
Lay ramp shall be equipped with a device to accurately determine the depth below the water
surface of the last roller (if applicable).
8. Pipe supports shall be designed so that they do not damage pipe coatings.
a. Pipe support rollers shall roll freely.
b. Pipe support geometry shall be checked before laying to ensure that it is in accordance
with installation engineering results.
9. Upon acceptance by Purchaser, the pipe installation vessel and major equipment shall not be
changed without prior written permission from Purchaser.
11.2
Installation Trials
1. Installation trials shall encompass operational and load tests of major equipment (e.g.,
winches, pipe support rollers, pipe stalking and line-up equipment, tensioners, cranes, welding
machines, and communication equipment) as specified by Purchaser or Purchaser’s certifying
verification authority (e.g., CVA or marine warranty surveyor [MWS]). These tests shall be
performed before barge mobilization in the presence of Purchaser representative(s) and
Purchaser’s CVAs.
2. Onboard static and dynamic testing of tensioners’ capacities shall be performed with the
coated pipe proposed for the project. The tension capacities of the winches shall be tested and
tension read-outs shall be calibrated.
3. Sufficient notice shall be given to allow Purchaser to witness the test.
4. Supplier shall submit installation trial procedures to Purchaser 60 days before mobilization for
sea trials.
5. If applicable, stinger equipment shall be checked in the water where possible. Stinger
equipment that cannot be checked in the water shall be tested on the surface before the stinger
is attached to the lay vessel.
6. Supplier shall submit the installation trials data book at the completion of sea trials and before
the start of offshore operations. Data book shall contain results of tests carried out during
installation trials.
11.3
Dynamic Positioning System Trials
1. Vessels shall meet the basic requirements defined below, as well as additional requirements
required by Purchaser marine experts.
2. DP vessels shall perform a field entry DP trial, before starting work, for the following reasons:
a. To ensure that positioning referencing systems, including but not limited to subsea
transponder arrays, are working and interfacing correctly with onboard system.
b. To ensure the onboard DP control systems and thrusters are working properly and that
thrusters have sufficient power output.
c. To demonstrate that the vessel can hold station in the weather and sea conditions expected
at that time, at a range of different vessel headings.
d. To demonstrate that the vessel can perform maneuvering tasks such as moving a set
distance to port or starboard, or both, under DP control, change heading by a preset angle,
and if, appropriate, follow a pre-programmed route or course.
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3. Supplier shall propose that maneuvers be performed during the DP trial. The field entry DP
trial shall be deemed to be successful if it is shown that all DP referencing systems are
working correctly and that the vessel is able to hold station at any chosen heading in the
prevailing weather and sea conditions over a period of not less than six hours.
4. Should any problems be found with either the position referencing systems, DP system
controls, or thrusters, the DP trials shall continue until those problems have been rectified to
the satisfaction of Purchaser representative onboard. If the fault cannot be rectified within the
allotted timeframe for the DP trial, the vessel shall return to port until the fault has been
rectified.
5. Purchaser representative onboard and vessel’s master shall both be fully satisfied that the DP
systems are working adequately during marine operations.
11.4
Personnel Transportation
1. Supplier shall provide transportation to, from, and between Supplier’s vessels, offshore living
quarters, or offshore facilities, and the onshore support base for Supplier’s personnel, and shall
accommodate Purchaser’s representatives when available.
2. Supplier’s transportation shall conform to all Purchaser HES policies.
11.5
Communication
1. Vessel shall be equipped with marine, and where appropriate, aircraft radio-telephone
communication equipment. All vessels in the spread shall be fitted with communication
equipment that is compatible with the other vessels in the spread.
2. A marine radio-telephone shall be fitted on the primary installation vessel to operate on the
channels in use in the relevant work site. In addition, the primary installation vessel shall be
equipped with a satellite communication capacity, online email, and telephone/telefax
connected to the relevant work site cellular telephone communications network.
3. Direct telephone, fax, and email communications shall be available between Purchaser office
and Purchaser representatives on the installation vessel.
4. Purchaser representatives on the vessel shall be provided radios compatible with the radio
communications used on the vessel.
5. Supplier shall provide equipment and necessary personnel to set up and maintain a video link
between critical support vessels or platforms for the duration of the installation scope.
a. Video link shall be visible in Purchaser office as well as other critical areas on the
installation vessel.
b. Video link shall provide transmit and receipt capabilities from all vessels and platforms.
6. Purchaser office shall have ability to view multiple cameras from pipelay vessel and shall
include the ability for Purchaser representatives to manually select different cameras.
11.6
Diving Operations
1. Supplier shall furnish required diving services, equipment, and supplies needed to install
pipelines and risers, mark subsea hazards and obstructions, and confirm that the pipeline has
been laid in accordance with Purchaser-accepted drawings and this specification.
a. Supplier equipment shall be in good and serviceable condition, shall be suited to safely
support the diving operations, and shall be maintained in these conditions during work.
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b. Equipment and procedures shall meet applicable industry regulations and any additional
Purchaser requirements.
2. A diving report, written in English, shall be submitted to Purchaser for review and acceptance
at the conclusion of each dive.
11.6.1 Procedures
1. Supplier shall submit procedures to Purchaser that cover types of diving Supplier
intends to employ (including general procedures). Detailed documentation shall be
submitted to Purchaser’s site representative before commencement of any diving
operation.
2. Diving equipment for placement and use on an offshore platform shall be rated for
possible ignitable concentrations of flammable gases, vapors, or liquids that may be
present within the atmosphere under abnormal operating conditions (i.e., Class 1,
Division II compatible).
11.6.2 Reporting Requirements
1. Supplier shall maintain diving logbooks and shall prepare incident reports per local
authority requirements.
2. Individual dive sheets shall be prepared giving details for each dive.
3. Documents shall contain the names of, and shall be signed by, the on-duty and any
relief diving supervisors.
4. Copies of these documents shall be provided daily to Purchaser.
11.7
Remotely Operated Vehicles
1. Supplier shall furnish ROV equipment and personnel support to determine and confirm that
the pipelines and risers have been installed in accordance with Purchaser-accepted drawings
and specifications. The use of ROV shall follow the following specifications:
a. SSM-SU-54.06
b. SSM-IT-54.17
c. SSM-PU-54.17
2. At a minimum, Supplier shall provide ROV inspection for certain phases of construction
specified in the scope of work. Some or all of the inspections in Table 3 may be required.
3. Supplier shall meet the following reporting requirements:
a. Supplier shall maintain ROV logbooks and shall prepare incident reports per local
authority requirements.
b. Individual ROV sheets shall be prepared giving details for each ROV dive.
c. Documents shall contain the names of, and shall be signed by, the on-duty and any relief
ROV supervisors.
d. Copies of these documents shall be provided daily to Purchaser.
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Table 3:
11.8
SSM-SU-5297.1
ROV Inspections
Inspection
Description
Pull Tube
ROV shall monitor the progress of the pull tube pulling operation, including
stringing of the pull cable, progress and position of the pipe and pull head, and
the pull tube mouth entrance angle.
Lay Initiation
ROV shall monitor the placement of deadman anchors (if applicable) and
initiation sleds, progress and position of the laydown assembly and pipeline,
and the touchdown point (TDP) of the pipeline. Specifically, ROV shall be used
to verify the position of the pipeline laydown head relative to the target area.
ROV shall also ensure that there is no interference between the pipeline or
laydown cable and any existing facility structures. ROV shall be used to provide
as-built data. ROV shall not be released until the deadman anchors have been
retrieved, laydown cables removed, and span verification has been
determined.
Touchdown
ROV shall visually monitor touchdown of the pipeline during the installation to
ensure the pipeline is properly aligned and positioned in the right-of-way and
laydown target area.
As-Laid Position
ROV shall be used to ensure that the specified pipeline TDPs coincide with the
planned route. This inspection shall be provided immediately following the pull
tube or lay initiation, and shall not be discontinued until after the pipe has
touched down beyond specified station number. If applicable, ROV shall verify
that there is no sliding or dragging of the pipe while laying the initial pipeline
curve.
Crossings and
Tie-Ins
ROV shall be used to monitor the TDPs of the new pipeline as it is laid across
pre-existing pipelines. Supplier shall ensure that the pipeline settles on top of
the pre-crossing protective material that shall have been placed at the crossing
location.
As-Built Survey
ROV shall be used to obtain all information necessary to produce certified
as-built drawings as required in this specification. ROV survey shall be
performed in one continuous pass. Supplier shall notify Purchaser of pipeline
free spans encountered during the ROV survey, and shall provide detailed local
pipeline and sea floor information for evaluation of the span within 48 hours of
discovery.
Riser Installation
ROV shall be used to monitor the complete platform riser installation and to
perform a complete visual inspection after the riser is installed. In conjunction
with the ROV riser inspection, a complete inspection shall be performed by
divers to verify integrity of pipe coating. Use of an over helmet camera is an
acceptable alternative to the use of an ROV.
Subsea Equipment
Positioning
ROV shall be used to monitor the installation of all subsea equipment
(e.g., PLETs and Suction Piles) to ensure that all subsea equipment is placed
in the correct position and in the correct orientation.
Positioning System
1. Supplier shall provide onboard surveyors to track the barge position and its relationship to the
right-of-way and to locate anchor placements.
2. Pipeline installation manual shall contain a detailed description of the barge positioning
system and the real-time display system the surveyors will use to monitor pipelay and hazard
locations, and support vessel and anchor locations.
3. Pipeline installation manual shall contain a detailed description of the barge mooring system
or DP system. If the barge has a DP system, a description of its capabilities, station-keeping
ability, and emergency procedures for failure of DP system shall be provided.
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4. Supplier shall provide, maintain, and operate adequate horizontal positioning systems to
determine the location of construction and survey vessels at all times. The complete system
used, including the locations of reference stations, frequencies, and other local system
characteristics shall be subject to Purchaser review and acceptance.
5. Purchaser shall furnish a preliminary map of all existing pipelines, risers, subsea structures
(PLETs) and appurtenances in the area of work.
a. It shall be Supplier’s responsibility to locate all subsea equipment in the installation area
before beginning work in the immediate area.
b. Supplier shall provide other necessary maps, nautical aids, navigational warnings,
transponders, and similar items required to properly and safely conduct work.
c. Additionally, Supplier shall provide position-fixing ancillary equipment such as line of
site, differential global positioning system (DGPS), radio systems, and radar to complete
work.
d. Supplier shall provide detailed survey procedures for Purchaser review and acceptance.
6. Supplier shall be solely responsible for the acceptable positioning and position fixing of the
installation vessel, survey vessels, and other installation spread equipment. See the DNV
“Rules for Classification of Ships,” Part 6, Chapter 7 – Dynamic Positioning Systems,
hereafter called DNV DP Rules.
7. Pipelay vessel shall comply with the requirements of classification group AUTR as defined
further in DNV DP Rules.
8. Experience records of DP operators shall be provided to Purchaser as requested.
9. DP system shall be adequate for all phases of installation including pipelaying, pipeline
initiation, laydown, and A&R operations.
10. DP control systems shall incorporate 100-percent redundancy to allow for failure of primary
positioning system inputs, partial loss of power, or other credible system failures and
contingencies. The positioning control system shall be demonstrated to the satisfaction of
Purchaser before the commencement of work.
11. Lay vessel positioning data and as-built survey data shall be accessible to Purchaser on the lay
vessel at all times during the installation. If requested by Purchaser, copies of the raw data
shall be made available to Purchaser.
11.8.1 Surface Positioning System
1. Supplier shall use redundant differential GPS positioning systems to ensure that the
accuracy of the continuous positioning of the installation vessel and its support vessels
(e.g., tugs, survey boat) is maintained, including during adverse weather or visibility
conditions and at night.
2. Supplier shall ensure that all floating craft and equipment exhibit adequate navigation
signals and warning lights.
3. Supplier shall provide real-time satellite positioning onboard the construction vessels.
a. Establishing and marking the route, and locating existing facilities, obstructions,
hazards, and the anchor handling tugs shall be performed from the construction
vessel.
b. Neither marker buoys nor magnetometer searches shall be used to verify existing
facilities, pipelines, or obstructions.
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c. Buoys shall not be used during installation to mark anodes, subsea connectors, or
curves.
4. In the event that a support vessel’s survey is different than that used by the Supplier,
Supplier shall ensure all survey providers actively and openly communicate with each
other for the purpose of survey integration.
5. Unless otherwise agreed with Purchaser, Supplier shall provide remote vessel
instrumentation on all vessels so every vessel may monitor the movements of other
vessels, as well as ROVs and subsea positioning activities.
11.8.2 Survey Equipment
1. Supplier shall provide survey equipment and personnel necessary to position subsea
equipment in the target boxes at all installation locations.
2. Supplier shall be responsible for installation and calibration of subsea acoustic arrays
required for installation activities.
3. Supplier shall provide a survey or ROV vessel equipped with suitable equipment and
personnel for installation and maintenance of the survey equipment necessary for the
positioning of subsea equipment in the installation scope.
4. Installation spread shall be equipped with the necessary survey equipment to position
the pipelay vessel for proper installation of the pipeline within the specified
tolerances.
5. Supplier shall be responsible for locating, installing, and calibrating required
positioning equipment. Supplier shall be responsible for the removal of any such
positioning equipment following completion of the pipeline installation and the
restoration of the site to its previous condition.
11.8.3 Survey Personnel
Personnel carrying out positioning shall include at least two qualified and competent
surveyors per shift, acceptable to Purchaser, who shall be available at the location at any
time during the execution of work.
12.0
CONSTRUCTION OPERATIONS
12.1
General
1. Laying techniques shall, at a minimum, be equal to industry practice.
2. Pipeline shall be placed in its final position on the ocean bottom without damage or distortion.
3. Supplier shall lay the pipeline on the ocean floor without overstressing the pipe or damaging
the coating.
12.2
Pipeline Monitoring and Control
12.2.1 Monitoring
1. Supplier’s barge engineer shall calculate the location of the pipe TDP in congested
areas using Purchaser-accepted pipelay stress PC program to ensure that adequate
separation is maintained between the pipeline and other seabed features, obstructions,
and facilities. This information shall be provided to the surveyors for inclusion in their
visual display.
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2. Supplier shall visually monitor TDP using an ROV continuously or as per project
technical requirement.
3. Supplier shall monitor and record the tension applied by each tensioning unit and their
sum on a continuous basis.
a. A chart recorder (or similar recording mechanism) shall be used.
b. Tensioner gauge readings shall be observed by Supplier personnel in the barge
control room each time the barge moves.
4. Supplier shall monitor and record WD every two hours.
5. Supplier shall monitor and record the depth of the stinger tail and all intermediate
sections on a continuous basis. Supplier shall conduct a visual survey every four
hours, or as required, to locate the pipe with respect to the stinger rollers.
6. Supplier shall monitor and record the following:
a. Tension in the A&R winch line, on a continuous basis when in use.
b. Wire payout/pay in for the A&R winch line, on a continuous basis when in use.
c. Wind speed and direction, and wave height, direction, and period, at least every
six hours.
d. Current profile (surface to seabed) once per shift, utilizing Purchaser-accepted
method from main pipelay vessel.
e. Wire payout/pay in and line tension on each mooring line winch.
7. Supplier shall record the following for each joint pull:
a. Time
b. Joint Number
c. Joint Length
d. Tension
e. Barge Heading
f.
WD
g. Touchdown Coordinate
8. Supplier shall log all of the parameters in item 7 a–g above, against local time.
12.2.2 Stress and Strain Control
1. Sufficient stinger support and tensioning devices shall be used during the various
operations to ensure that stresses and strain along the pipeline are within the stated
allowables given in Table 4 and Table 6.
2. Supplier shall provide instrumentation for a continuous visual display and permanent
record of readouts for Purchaser to monitor the barge-applied tension (a tension chart
recorder) and stinger configuration.
3. No permanent deformation shall be introduced in the pipe during the welding or the
lowering-in operations. If a pontoon or stinger is not used, the angle of approach of the
inclined ramp on which the pipe joint(s) are welded together may not introduce
combined stresses in the pipe in excess of the overbend as given in Table 4 or Table 6.
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4. Minimum allowable radius to which the pipe may be bent during the lowering-in
process shall be such as to allow the pipe to be laid without exceeding the stress
limitations specified herein. In no instance shall a bend be made that exceeds the
allowable stress limitations.
5. Maximum tension variation during move-up shall be limited to less than 10 percent of
the nominal tension.
a. Stinger depth shall be monitored visually with a gauge.
b. A TV monitor showing a view of the stinger rollers and the pipe shall be provided
in the barge control room.
c. Stinger attitude variation shall be limited to that established by the parametric
stress analysis studies.
6. Stress and strain control and stress and strain monitoring for risers, as well as pipelines
during the entire installation, shall be in accordance with the requirements in this
section. During riser installation, the maximum combined stress shall not exceed
allowables given in Table 4 and Table 6.
12.2.3 Buckle Detection
1. Supplier shall provide a buckle detector if pipelay analysis shows that the pipeline
cannot be laid fully flooded.
2. Supplier shall prepare a buckle detection procedure for review and acceptance by
Purchaser.
3. Buckle detection procedure shall be included in the pipeline installation manual.
12.3
Supplier Reporting
12.3.1 Schedule of Work
1. A chronological schedule of work shall be prepared by Supplier before the initiation
of offshore construction, showing estimated completion times of key activities.
2. Schedule shall include each pipeline, each riser, and other operations and marine
vessels individually.
3. Schedule shall be included in the pipeline installation manual and shall be updated as
necessary, during construction and as the project progresses, to reflect actual and
forecasted events.
12.3.2 Daily Field Reports
Supplier shall prepare a daily activities report by 4 A.M. each day to submit to Purchaser
for acceptance. Daily report shall include, as a minimum, the following:
1. Daily forecast of work to be performed over the subsequent 24 hours, and
present/future known vessel locations and movements.
2. Status of all operations.
3. Time log around the clock for activities directly or indirectly affecting the pipelaying
operation.
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4. Pipe tally showing joint numbers, pipe section lengths, and weights of pipe installed.
A pipe tally report shall be submitted upon completion of each pipeline, and shall be
in both English and metric units.
5. Daily radiography reports detailing all welds and repairs to welds.
6. Field joint coating inspection and repair.
7. Pipe joints removed from the pipeline due to damage or in accordance with this
specification.
8. Barge position at two-hour intervals and respective WD.
9. Current profiles from past 24 hours.
10. Hourly recording on Purchaser pipeline laying data sheet.
11. Diving reports shall be submitted upon completion of each dive.
12. Incident reports shall be submitted within 24 hours for any person receiving treatment
from Supplier’s medical personnel for any injury.
12.4
Supplier Safety
12.4.1 General Safety
1. The intent of these safety regulations is to outline procedures, and the regulations shall
supplement, not replace, Supplier’s safety program.
2. Purchaser shall reserve the right to require the dismissal of Supplier personnel, or
termination of contract, if an appropriate safety program is not followed, or for
deviation from the following:
a. Supplier shall request clarification if there is a conflict between this specification
and IIF requirements.
b. All personnel shall wear local authority-approved safety hats and shoes.
3. Safety is of prime importance to Purchaser, and pipeline installation manual shall
include a description of Supplier’s criteria for safe operations, including crane
operations.
12.4.2 Personnel Safety
1. Smoking shall be permitted in designated areas only.
2. Proper eye protection shall be worn at all times on deck and other designated areas.
3. Purchaser-accepted work vest or life jacket, furnished by Supplier to their personnel,
shall be worn and buckled during over-water transfers and when working near or over
water where there are no handrails.
4. Horseplay, wrestling, alcohol, and practical jokes shall be prohibited.
5. Supplier shall notify all employees and related subcontract personnel, in writing, of
Purchaser’s policy prohibiting illegal drugs, pyrotechnics, firearms, dangerous
weapons, and other contraband on premises and work locations controlled by
Purchaser.
6. All of Supplier’s cranes shall be operated by qualified, authorized, experienced
crane operators thoroughly familiar with Supplier’s safe operating procedures and
API RP 2RD.
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12.4.3 Work Safety
1. Crane shall be operated only by capable and qualified personnel.
2. Power tools shall be grounded and in good condition.
3. Before hot work is authorized or started on any platform or within a platform’s
1640-foot (500-m) safety zone, there shall be thorough communication between
Purchaser and Supplier.
a. Nature of work to be performed and all possible hazards shall be discussed in
detail.
b. Authorization for hot work shall be evaluated on a daily basis.
4. No cutting, welding, or sandblasting shall be performed on operating platforms until a
hot-work permit form is authorized in writing by Purchaser’s production supervisor.
a. Purchaser representative in charge shall assist with securing this authorization.
b. Supplier shall submit a written request to Purchaser for hot work permits or any
other work permits a minimum of 24 hours before they are needed.
5. On operating platforms, all persons shall become familiar with the functions and
locations of platform’s emergency shutdown (ESD) and fire stations.
6. An open flame shall not be used to detect gas leaks.
7. There shall be a Supplier-furnished fire watch established on platforms before the
work is started.
a. Fire watchman’s only duty shall be that of fire watch.
b. Fire watchman shall know how to operate fire extinguishers properly and shall
have an extinguisher on the site at all times near the work to be done.
8. Welding machines used on platforms shall be equipped with a spark-arresting muffler.
9. Before arrival on site, Supplier shall inspect marine vessels and pipelaying equipment
for safety hazards, and shall provide Purchaser with a report, including a plan to
correct any violations.
10. Supplier shall anticipate impact of Purchaser safety requirements on the installation
work schedule.
a. In general, work shall be allowed on a 24-hour-a-day basis except for hookup
work on platforms where lighting is restrictive.
b. Movement of anchors or moorings in the vicinity of existing facilities (platforms
or pipelines) shall generally not be permitted at night.
c. Lifting of equipment onto decks shall not be permitted at night.
d. Hot work at night on live facilities shall be prohibited unless specific written
authorization is obtained from Purchaser in the hot work permit form.
11. Unless otherwise agreed with Purchaser, Supplier shall give a minimum of 24 hours
notice to Purchaser before moving barges at night. Supplier’s first approach to the site
shall be done during daylight hours.
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12. Communications between the surface and divers is an important safety consideration,
and Supplier shall provide equipment for monitoring noise and sound levels on the
barge. Supplier shall provide equipment and facilities on the barge that assist diver
communication in a high noise environment.
13. Supplier shall describe, in pipeline installation manual, the safety procedures to be
used during NDT, including shielding for both pipeline and riser construction.
12.5
Supplier Anchor Handling, Mooring, and DP Requirements
1. Supplier shall provide vessel mooring drawings for Purchaser review and acceptance.
Drawings shall be included for the following:
a. Pipeline initiation
b. Pipeline laydown
c. Riser installation
d. Burial and trenching
e. Pipeline crossings
f.
Curved route
2. Drawings provided by Supplier shall show all existing pipelines as dotted lines, and lines to be
installed as solid lines.
3. Anchor drag monitoring program shall be used.
a. Anchor lines shall be buoyed off when an anchor line crosses the existing pipeline.
b. Catenary calculations shall be provided.
c. Mooring analysis shall be submitted.
4. Supplier shall take all necessary precautions to prevent pipeline damage from anchor spread.
a. Anchor handling vessel shall be equipped with a radio positioning system.
b. Before dropping an anchor, the vessel Captain shall obtain acceptance of his location from
Supplier’s authorized representative onboard the lay barge.
5. No anchors or anchor cables shall be placed within 500 feet (152 m) of a chemosynthetic
community.
6. Any anchor that will be located using the minimum horizontal distances shall require
acceptance of Purchaser before dropping. The minimum horizontal distances shall be the
following:
a. ~150 feet (~50 m) for pulling on an anchor away from or parallel to a pipeline.
b. ~300 feet (~100 m) for anchors pulled toward a pipeline.
7. All anchor locations shall be reported.
a. Any anchor dragging shall be reported immediately to Purchaser representative or
inspector.
b. If an anchor is suspected to have been dragged, the position of the anchor shall be
investigated and the pertinent mooring parameters (time, anchor position, pipelay vessel
position) shall be recorded in the anchor log.
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8. Purchaser shall not allow anchors or cables to be dragged along bottom.
a. Anchors shall be picked up vertically so as not to damage pipelines and structures.
b. Supplier shall present procedures to assure Purchaser of compliance with the minimum
vertical distances between the cable and pipelines and the minimum horizontal distances
between an anchor and a pipeline.
c. Mooring drawings shall show lightening buoys, where required.
9. Supplier shall indicate in pipeline installation manual whether they plan to moor to
Purchaser’s platform(s) for riser installation. If so, Supplier shall identify line attachment
location(s) on the construction drawing(s).
10. Supplier shall be allowed to perform the lay operations on a 24-hour-per-day basis with certain
activities prohibited at night, as noted in Section 12.4 above. Supplier shall indicate in
schedule those activities to be performed at night, and shall submit this schedule for review
and acceptance by Purchaser.
11. If Supplier installation vessel uses a DP system, Supplier shall provide details on the
following:
a. DP system capabilities.
b. Station keeping ability.
c. Possible drift of vessel.
d. Emergency procedures for DP system malfunction.
12. Purchaser may at its own discretion require Supplier to demonstrate capabilities of mooring
system, DP system, or both by performing DP system trials or anchor handling demonstrations
upon mobilization into country, before move into work site.
12.6
Pipeline Abandonment and Recovery
1. Supplier shall safely abandon pipeline if weather, seas, or malfunction of laying equipment are
of sufficient magnitude to endanger the pipeline.
a. Pipeline recovery shall be initiated with the return of favorable environmental or operating
conditions.
b. During pipeline A&R phase, allowable stresses and strain shall not exceed limits in
Table 4 or Table 6.
2. In abandonment, Supplier shall securely seal the pipe end with a welded pipe cap, and lower
the pipe from the lay barge to the seafloor with a holdback cable to maintain tension in the
pipeline.
a. Supplier shall properly mark the abandoned line with a buoy in the event of leaving
the site.
b. An acoustic pinger shall also be used to mark the end of the pipeline.
3. Pipelaying operation shall be suspended if major equipment malfunction or failure occurs that
endangers the safety of personnel or of the pipeline and associated facilities.
4. Purchaser shall be consulted before suspension or resumption of the laying operation.
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13.0
WELDING
13.1
General
SSM-SU-5297.1
1. Welding shall conform to the latest edition of API STD 1104 and Purchaser-specific welding
specification.
2. If Supplier identifies any discrepancies in Purchaser documentation, Supplier shall request that
Purchaser clarify. Unless otherwise clarified by Purchaser, Supplier shall assume that the most
stringent requirement governs.
3. With bid and proposal a weld matrix shall be provided identifying proposed weld procedures
along with critical items (i.e., bevel design, test requirements, material, and NDE information).
This matrix shall be maintained throughout the entire project and shall be updated as required
to reflect the most up-to-date status of the project welding requirements.
4. WPQs shall use the same NDE equipment and processes that will be used during production.
a. This most often requires the NDE equipment and procedures to be qualified in advance of
the welding procedures.
b. Supplier shall make the necessary arrangements into their overall schedule to account for
this requirement.
5. Welders shall be allowed only two attempts to qualify. Repeated failures in attempts to qualify
shall be subject to Purchaser acceptance.
13.2
Weld Repairs
1. Supplier shall perform weld repair in accordance with SSM-SU-5003.
2. Weld repair calculation shall be provided to show allowable weld flaw size (length and depth)
along the circumference of the pipeline at each weld repair station, based on maximum lay
tension expected at different segments along the pipeline.
14.0
FIELD JOINT COATING
Supplier shall provide field joint coating in accordance with Purchaser-specified requirements.
15.0
FIELD REPAIRS TO PIPELINE COATING DAMAGE
15.1
General
1. Supplier shall repair any pipe coating damage in accordance with appropriate industry
standards and Purchaser specifications, based on accepted procedures.
2. Purchaser shall make the final decision as to when damage has occurred, or to what extent
damage has occurred to the pipe.
3. Assessment of damage and repair or replacement of the damaged section shall be in
accordance with relevant Owner Subsea Pipelines coating specification(s).
4. Purchaser acceptance of a repaired length of pipe shall be required before Supplier
incorporating it into the pipeline.
5. In the case of damage that is beyond the repair level deemed permissible by Purchaser,
damaged pipe joint shall be replaced.
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15.2
SSM-SU-5297.1
Damage and Repair During Handling
1. Supplier shall make no welding repairs on dents, grooves, deep scratches, gouges, major arc
burns, or other defects that may affect the integrity of the parent metal of the pipe. These types
of defects shall be cut out from the pipe.
2. Dents that affect the curvature of the pipe at the circumferential weld shall be removed.
3. Pounding out or jacking out of dents or of out-of-round pipe shall be strictly prohibited.
15.3
Corrosion Coating
1. Field repairs to corrosion coatings shall be accomplished by Supplier with material and
methods compatible with the parent coating. For fusion bonded epoxy (FBE) coatings this
shall be a two-part epoxy patch coating system recommended by the corrosion coating
manufacturer, or a material accepted by Purchaser.
2. Coating repairs shall be made in accordance with manufacturer’s recommendations and
Purchaser-accepted coating repair procedures.
3. For underwater repair work, the repair method and material shall be proposed by Supplier.
a. Repair method shall provide protection equal to the design coating in all respects.
b. Design coating protection shall include, but not be limited to, the following:
1) Corrosion prevention
2) Impact protection
3) Pipe stability
c. Complete details of the repair method and material shall be submitted to Purchaser for
acceptance before use by Supplier.
15.4
Riser Coating Damage and Repair
1. Pipe cleaning and repair of riser coating shall be performed by Supplier per this specification
and the manufacturer’s recommendations.
2. If coating damage is too substantial to be repaired with the neoprene material in one split
sleeve, the joint shall be rejected.
Note
For small holidays or damaged areas, a patch may be cut from the sleeve to fit
the cleaned area rather than removing a strip around the entire circumference of
the pipe.
3. All repairs shall be covered completely with a shrink sleeve. Adequate time shall be allowed
for epoxy bond material to cure to a degree suitable for handling before passing the repair over
barge rollers.
4. Additional heating of the shrink sleeve may be employed to accelerate curing, however
temperatures shall be kept within the manufacturer’s recommended limits for all components.
15.5
Concrete Weight Coating
1. Before loading each joint of pipe onto the lay barge, Supplier shall inspect for damage to the
weight coating.
a. Should damage be discovered before loading, Supplier shall make all necessary repairs.
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b. Any repairs to concrete coating shall be made a minimum of 36 hours before further
handling.
2. The following criteria shall be used by Supplier for repairing hardened concrete weight
coating that has spalled due to compression or shearing caused by impact against other objects.
a. Damage caused by local spalling (a loss in concrete of more than 15 percent of the total
thickness of the coating at the point of damage) of an area less than 1 square foot
(300 square mm) where the remaining concrete is sound shall be accepted without repairs,
as long as Supplier demonstrates to Purchaser that the coated pipeline can be installed
safely.
b. Damage caused by spalling of an area more than 1 and less than 3 square feet (more than
300 and less than 900 square mm) shall have the remaining concrete in the damaged area
removed as necessary to expose the reinforcing steel throughout the damaged area.
1) Edges of the spalled area shall be undercut so as to provide a keylock for the repair
material.
2) A stiff mixture of grout or cement, water, and aggregate shall be trowelled into and
through the reinforcement and built up until the surface is level with the coating
around the repair.
3) The coating shall be moist-cured a minimum of 36 hours before further handling of
the pipe.
4) Pipe shall then be carefully laid with the repaired area topmost.
c. Damage caused by spalling of an area of more than 3 square feet (900 square mm) shall
have the coating removed around the entire periphery of the pipe throughout the damaged
area.
1) A repair shall be made by restoring the reinforcing with a metal form and pouring a
complete replacement of concrete or grout.
2) The mixture shall be 1 part cement to 3 parts of aggregate and the necessary water to
produce a slump not to exceed 4 inches (102 mm).
3) Resulting coating shall be equal in weight, density, uniformity, thickness, strength,
and characteristics to the originally applied coating.
4) Pipe shall then be carefully laid in a position where it shall be allowed to remain a
minimum of 36 hours before further handling.
d. If the concrete weight coating is damaged to the extent that it is loose from the pipe and
subject to spalling, it shall be repaired by removing loose material and replacing it with
Purchaser-accepted concrete infill product. Purchaser’s decision concerning the
determination of what is loose weight coating and subject to spalling shall be final.
3. For damage to both concrete weight and corrosion coatings, Supplier shall remove all concrete
weight coating material within 3 inches (75 mm) in all directions of a defect. The area shall be
tapered to the outside on a slope of approximately 2 parts vertical to 1 part horizontal.
a. Supplier shall remove any intermediate and corrosion coatings within 2 inches (50 mm)
of the defect.
b. Supplier shall then wire brush the defect area, taking care to feather into the undamaged
corrosion coating surrounding the defect.
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c. Immediately following, Supplier shall patch the corrosion coating using a 2-part epoxy
patch coating system recommended by the corrosion coating manufacturer.
d. Remainder of the patch shall be of Purchaser-accepted concrete infill product.
e. Supplier shall place a permanent metal or polyurethane protective form covering all
repaired areas on the pipeline.
15.6
Testing of Coating Repairs
1. Before submersion of the pipe, Supplier shall subject all field repairs to coatings to a
continuous electric holiday detector test or jeep test to check for holidays, pinholes, and
discontinuities. This test shall be conducted to the satisfaction of Purchaser.
2. Detector shall be an agreed-upon circular ring with indicator.
3. Test voltage shall be between 100 and 150 VDC per nominal mil of coating.
4. Defects shall be repaired and re-tested and reported to Purchaser.
15.7
Pipe Damage
1. Dents and buckles shall be removed from the pipe by cutting the damaged length from the line.
a. Cutout shall be the length of the damaged area plus at least one pipe diameter on each side.
b. Pipe shall then be rejoined by a girth weld in compliance with this specification.
c. Field joint coating shall also be applied as described in this specification.
2. Damage detected before passage of the damaged area into the water shall be immediately
repaired.
15.8
Damage and Repair During Installation
1. Supplier shall repair or replace any damaged pipe, weld, anode, field joint coating, or
yard-applied coating that affects the useful life or mechanical integrity of the pipeline.
2. Supplier shall be responsible for all damages that occur during the time from Supplier’s pipe
acceptance until the time of acceptance of any section of the pipeline by Purchaser.
3. When damage has occurred to the pipeline, Supplier shall immediately notify Purchaser.
a. Purchaser shall make the final decision as to whether or to what extent damage has
occurred to the pipe.
b. Any pipe that is dented, out-of-round, or has a wall thickness reduction more than that
allowed by project requirements shall be replaced.
c. Purchaser shall decide what amount of the damaged pipe can be repaired, and what
amount shall be replaced.
d. Assessment of pipe damage and repair or replacement of damaged pipe shall be in
accordance with this specification.
4. Supplier shall submit written procedures on the proposed method of rigid pipeline repair to
Purchaser as part of installation manual. These procedures shall include, but not be limited to,
damage resulting from pipe dry buckle during installation, pipe wet buckle during installation,
and on-bottom damage.
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5. Supplier shall provide repair procedures for pipe damage, including underwater damage to
coatings and anodes, to Purchaser as part of installation manual. These procedures shall
include damage that is detected after the pipe is laid into the water.
6. Repair procedures shall also include all WDs encountered along the pipeline route, and shall
cover different quantities of pipeline damage. In addition, the procedures shall include at least
the following:
a. Details of method to abandon or recover a flooded pipeline.
b. Details of the equipment that will be used to recover and repair the damaged pipeline.
c. Details on dewatering the pipeline, if necessary.
7. Repair procedure shall fully describe the connection methods used to affect the subsea repairs
for the pipeline and for all WDs along the pipeline route.
8. If moving, lifting, and aligning of the pipeline end are required, the provisions of this
specification shall be followed with respect to procedures, pipe stress, and all other aspects of
installation.
9. Supplier shall describe in the repair procedure how they propose to remove the damaged
section of pipe from the sea floor, and Purchaser’s representative shall make the final decision
as to which repair method is to be used.
15.9
Weight Coating Damage Detected Below Water
1. Acceptance criteria for weight coating after laying the pipeline on the sea floor shall be as
follows:
a. Cracking shall not be cause for rejection.
b. Loose or spalled concrete up to 10 percent of the surface area of individual joints shall be
allowed with no requirement to restore nominal design negative buoyancy.
c. Spalling in excess of 10 percent of the surface area of a joint or areas of spalling on
adjacent joints shall be reviewed on a case-by-case basis to determine the need to restore
nominal design negative buoyancy.
2. Repairs to damaged coating shall be as follows:
a. Procedures to repair damage shall be accepted by Purchaser before start of repair activity.
b. Loose or partially spalled concrete shall be removed if necessary to ensure concrete wire
reinforcement does not touch the pipe, and to allow visual inspection of corrosion coating.
c. Corrosion coating shall be repaired as necessary in accordance with an accepted
underwater procedure.
d. If repairs are required to restore negative buoyancy, concrete mattresses shall be placed
over the pipeline.
15.10 Deepwater Pipeline Repair
Deepwater pipeline repair shall be made in accordance with Purchaser-specified requirements.
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16.0
ANODE ATTACHMENT AND COATING REPAIRS
16.1
General
SSM-SU-5297.1
1. Aluminum-zinc-indium alloy anode bracelets shall be provided by Supplier in accordance
with the following Purchaser specifications:
a. SSM-SU-52.01
b. SSM-DU-52.02
2. Anode shall not contact any protective metal banding integral to wire mesh reinforcement
required for concrete weight coating.
16.2
Anode Attachment
Anodes shall be attached in accordance with SSM-SU-52.01.
16.3
Corrosion Coat Repair (After Anode Attachment)
1. After the anode has been installed, the weld area shall be thoroughly cleaned with a wire
brush.
2. The corrosion coat on all steel surfaces shall be repaired, including the pipe bonding plates that
have been exposed for welding purposes.
3. Care shall be exercised to prevent the coating from touching the outer face of the anode.
4. Damage to the pipe corrosion coat shall be repaired as specified in Section 11.0.
16.4
Concrete Weight Coating Repair (After Anode Attachment)
For field-installed anodes, the concrete weight coating repairs around anodes shall be applied by
Supplier as specified in Section 11.0.
16.5
Inspection and Acceptance
1. During installation of the anodes, all aspects of the installation process shall be made available
for inspection by Purchaser.
2. Any anode assembly not meeting the requirements of Purchaser drawings, SSM-SU-52.01,
manufacturer’s recommendations, and referenced documents may be rejected.
3. Rejected assemblies shall be dismantled and reassembled in compliance with the requirements
of this specification.
17.0
PIPELINE RISER INSTALLATION
17.1
General
1. Supplier shall install risers using one of the following methods:
a. Pre-installed J-tube with diver assistance, ROV assistance, or both.
b. Conventional above-water pipeline-to-riser welded.
c. Pre-installed conventional riser with ring-type joint (RTJ)-type end connections.
d. I-tube.
e. Top tensioned riser (TTR).
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f.
SSM-SU-5297.1
Steel catenary riser (SCR).
g. Steel lazy-wave or lazy-wave flexible riser.
h. Hybrid riser.
2. Supplier shall submit proposed installation method to Purchaser for review and acceptance
before procurement of material.
17.2
Conventional Risers
17.2.1 Clamps
1. Bolted clamps shall be used to attach the riser to the fixed platform structure below the
waterline.
a. Clamps welded to the jacket shall be used above the waterline.
b. The clamp on the pipeline riser shall be bolted.
c. Bolting shall be studded with double nuts with washers on each end.
d. Bolting and nuts shall be Teflon-coated or Purchaser-accepted equal.
2. Riser clamps shall have a 1/2-inch (12.5-mm) thick neoprene or vulcanized rubber
liner such as neoprene or equivalent installed between the clamp and the pipeline riser.
17.2.2 Anodes
1. Sacrificial anodes shall be placed on the riser assembly when required by the anode
design.
2. Supplier’s cathodic protection design shall be submitted for review and acceptance by
Purchaser.
3. Anodes shall be placed a minimum distance of 5 feet (1.5 m) from a riser clamp.
17.2.3 Pipeline Repositioning
1. Davit lifts and any other procedures for pipeline repositioning shall be planned and
executed to avoid over-stressing or buckling the pipeline.
2. Supplier’s procedure shall be submitted for review and acceptance by Purchaser.
17.2.4 Riser Fabrication
1. Supplier shall fabricate the risers and associated clamps as required by this
specification.
2. Risers shall be fabricated with an extension of 30 inches (762 mm) at the riser bend,
when the pipeline is required to be buried for the first 200 feet (61 m) plus from the
riser bend, and tapering to the seafloor as described in project technical requirements.
3. When required, diagonal bracing shall be attached to the riser bends in the plane of the
bend. The bracing shall be welded to the welding sleeves provided on the riser bends.
17.2.5 Riser Coating
1. Riser assembly above the splash zone shall be coated as required by project technical
requirements.
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2. Splash zone shall be coated with a layer of 1/2-inch (13-mm) minimum thickness of
Splashtron or Purchaser-accepted equivalent.
a. Application shall be in accordance with manufacturer’s instructions.
b. Minimum coated length shall be one 30-foot (9.1-m) continuous section.
c. Coated joint shall be installed in the riser equidistant above and below the LAT.
3. Below the splash zone, the riser shall be coated with the same corrosion coating or
insulation as the pipeline. If the risers are coated onshore, any damage received during
installation shall be repaired.
17.2.6 Riser Installation Procedure
1. Riser and pipeline tie-in procedures shall be submitted to Purchaser for review and
acceptance 120 days before start of installation operations. These procedures shall be
described in the pipeline installation manual.
2. Riser pipe shall be welded and inspected in accordance with Section 9.0.
3. Supplier shall include a procedure that includes a description of the equipment to be
used for boat landing and riser protector removal and reinstallation.
4. Riser clamps shall be attached to the platform jacket before riser installation.
a. Riser clamps shall fit loosely around the riser during riser installation to permit the
riser to sink to its specified elevation.
b. Riser clamps shall be tightened after flooding and before final pigging has been
completed.
c. Cables or clamps shall not be attached to the riser assembly below the
minus ~20-foot (~6.1-m) elevation.
5. Unless agreed to otherwise by Purchaser, welded connections between the pipeline
and risers or flanged pre-installed risers shall be used in WDs less than ~305 feet
(~100 m). For WDs in excess of ~305 feet (~100 m), pre-installed risers, SCRs, or
J-tubes shall be used.
17.3
J-Tube Risers
17.3.1 General
1. This section shall govern the minimum requirements for J-tube riser installation.
Installation of the J-tube riser shall be in accordance with installation procedures
prepared by Supplier for Purchaser’s review and acceptance.
2. Purchaser’s acceptance of Supplier’s installation methods and procedures shall not
relieve Supplier of responsibility for the safe and efficient installation of the J-tube
riser to the satisfaction of Purchaser.
3. Each J-tube riser pull procedure shall be supported by design and installation
calculations accepted by Purchaser.
4. A minimum of 120 days before the scheduled start of pipeline installation, Supplier
shall submit, at minimum, the following items for Purchaser’s review and acceptance:
a. Procedures for J-tube riser installation.
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b. Certificates for the chemicals to be used during J-tube installation.
c. Written procedures on the proposed methods of inspection of the J-tube riser.
17.3.2 Riser Coatings
1. Riser shall be coated along its full length with accepted 1/2-inch (13-mm) minimum
thickness polychloroprene or equivalent, or a Purchaser-accepted insulation coating,
with the exception of the first 15–20 feet (4.5–6.1 m) of pipe, which shall be coated
with fusion-bonded epoxy and shall be cut off after riser installation.
2. Each joint of riser-coated pipe shall be aligned on the pipe string so that the direction
of the radial ridges on the surface of the riser coating will be with the J-tube pull, and
not against it. Arrows in the direction of the pull shall be painted on each joint by the
coating manufacturer.
17.3.3 Field Joints
1. All surface preparations for the J-tube riser field joint shall be carried out when the
pipe is dry.
a. After the field welds have been radiographed and visually examined and accepted
by Purchaser, the uncoated portion of the pipe at the field joints shall be
thoroughly cleaned by use of accepted abrasive wheels until a uniform grey-white
metallic color is obtained.
b. Supplier shall remove any coating not firmly bonded to the pipe and the field joint
surface shall be free of grease, moisture, dirt, rust, weld spatter, and other foreign
material that may impair the proper bonding of the neoprene or equivalent split
sleeve.
2. A quick-setting, two-part epoxy, 3M 2216 B/A Structural Adhesive, shall be applied
to the field joint area and edges of plant-applied polychloroprene coating. Epoxy shall
be applied per manufacturer recommendations.
3. Polychloroprene or equivalent split sleeve shall be fitted around the joint with a
2-inch (51-mm) overlap at the longitudinal seam.
a. Bottom layer of the polychloroprene where it overlaps at the sleeve’s longitudinal
seam shall also be coated with two-part epoxy.
b. Sleeve shall be temporarily held in place with tape while a shrink sleeve is
installed over it.
c. Shrink sleeve shall be installed per the shrink sleeve manufacturer’s instructions.
Sleeve shall be heated for a minimum of 3 minutes to promote curing of the
neoprene bonding epoxy.
4. The field joint area shall be visually inspected after cleaning and after coating to
confirm that it meets the requirements of this specification. Supplier shall inspect the
field joint with a full circle electronic holiday detector. No holidays shall be
acceptable.
a. Spot checks by sounding shall be performed at Purchaser’s request.
b. Purchaser shall accept, reject, or request repairs to a Purchaser-accepted
procedure for all flaws. Rejected coating shall be removed and the field joint area
cleaned and re-coated per requirements of this specification.
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17.3.4 Installation Procedure
1. Riser installation procedure shall produce the minimum possible pull tension.
a. Supplier shall continually determine by visual means that no obstructions to pipe
entering the J-tube exist, and that the pipe is in line with the J-tube until the pull
head has entered and traveled at least 40 feet (12.2 m).
b. Supplier shall remove obstructions to the entrance of the J-tube.
c. Cable tension shall be applied smoothly without tension surges.
2. A joint of pipe with a J-tube stopper shall be installed in the line so that after the J-tube
has been pulled, the stopper is firmly lodged inside the J-tube, sealing the bottom of
the J-tube annulus from the external seawater.
3. Once the riser has entered the J-tube, a minimum length of 500 feet (152 m) of the
pipeline shall be in contact with the seafloor between the J-tube entrance and the
installation vessel. Supplier shall ensure that, except for pipe inside the J-tube, the
stress during installation shall not exceed 80 percent of the yield strength.
4. After the riser has been pulled through the J-tube, Supplier shall treat the water in the
J-tube annulus with chemicals providing bactericide, corrosion inhibitor, and oxygen
scavenger functions.
a. Concentrations used shall be sufficient to protect the J-tube annulus for the
specified design life.
b. A J-tube stopper shall be placed in the top of the J-tube after introduction of the
chemicals to seal the J-tube annulus.
c. Supplier shall provide stopper design for review and acceptance by Purchaser.
5. All chemicals shall be used and disposed of per manufacturer recommendations and
local regulatory requirements in a way that does not harm the environment.
a. Technical data on any chemicals and manufacturer’s recommended dosage for use
shall be submitted with the pipeline installation procedures.
b. Supplier shall also provide material certificates for each chemical used to treat the
seawater.
6. Supplier shall secure the top of the J-tube riser pipe to the J-tube with an anchor
support clamp.
17.3.5 Installation Monitoring
1. During J-tube installation, Supplier shall monitor the installation equipment to
determine that the installation work is performed in accordance with the procedure.
2. In particular, Supplier shall monitor the pull winch and tensioners during J-tube riser
pull operations.
3. Supplier shall provide instrumentation to measure J-tube riser pull winch tension
(continuously recorded on a strip chart or equivalent).
17.3.6 Subsea Inspection and Survey
1. Supplier shall provide, at its own expense, the diving and ROV services needed to
install and inspect the riser.
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2. As part of the subsea inspection surveys, Supplier shall provide videos of the
following:
a. Completed installation of the riser, including the pipeline as it leaves the bottom
of the J-tube.
b. Pipe pull into the J-tube bell mouth, as well as the seating of the J-tube stopper.
3. For the J-tube(s), Supplier shall inspect the messenger cable before the J-tube riser
installation to ensure that the messenger line has not been fouled and that it can be
retrieved without difficulty.
4. The pipe pull into the J-tube bell mouth shall be inspected, as well as the seating of the
J-tube stopper.
17.4
Pre-Installed Risers
17.4.1 General
Pre-installed risers shall meet the requirements of conventional risers.
17.4.2 Riser Fabrication
1. Risers shall be fabricated and tested before installation. Testing shall include pigging
with a gauging pig and a hydrostatic pressure test.
2. Pre-installed risers shall be pressurized with air before transportation and launch of
the jacket structure.
3. Risers shall be equipped with RTJ flanges at top and bottom. Additional flanges or
connections along the length of the riser shall not be installed without prior Purchaser
review and acceptance.
17.4.3 Riser and Pipeline Tie-in
1. Where WDs permit, the pipeline shall be tied into the riser without a flanged spool
piece.
2. Where WD limitations require the use of a flanged spool piece, the spool piece shall
be constructed out of line pipe with swivel flanges on each end.
a. Misalignment ball joint flanges may also be used, but Supplier should attempt
to minimize their use if possible. Supplier shall provide the misalignment ball
joint flange specifications and qualifications for Purchaser review and
acceptance.
b. Riser pipeline flanges shall be standard RTJ flanges.
3. Flanged spool piece shall be coated as required by the project technical requirements.
4. Supplier shall adjust the pre-installed riser to meet burial requirements. When burial is
not a requirement, the pipeline and riser shall rest on the seafloor.
17.5
Steel Catenary Risers
1. SCR pipes fabrication, assembly, and installation shall as a minimum use the same
requirement with allowable strain for pipeline installation as given in Table 6. SCR pulling
through pull tube shall be in accordance with Section 16.3.
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2. Supplier shall provide SCR installation procedures for Purchaser review and acceptance.
Note
17.6
This specification does not address the SCR transfer procedures requirement and
interface with the host.
Flexible Riser
1. Flexible riser installation shall be in accordance with Purchaser requirements.
2. Supplier shall provide installation procedures for Purchaser acceptance.
17.7
Hybrid Riser and Top Tension Risers
Hybrid riser and top tension riser installation shall be covered separately. Supplier shall provide
installation procedures for Purchaser review and acceptance.
18.0
PIPELINE BURIAL AND TRENCHING
1. If pipeline burial or trenching is required in scope of work, Supplier shall provide a procedure
for acceptance by Purchaser.
2. Minimum trenching or burial depth shall be 30 inches (762 mm) above top of pipe unless
otherwise stated in the project technical requirements.
3. Supplier shall select trenching equipment and shall design trenching operations to meet the
following requirements:
a. To avoid damage to coatings or pipeline.
b.
To ensure that stress levels do not exceed 85 percent of yield.
4. As an alternate to burial or trenching for dropped object protection, Supplier may recommend
the use of concrete mats. Prior review and acceptance by Purchaser shall be required for this
method.
19.0
INSULATING FLANGES
1. Insulating flanges shall be installed at the riser-to-platform piping connection. Insulating
flanges shall be designed to prevent electrical current flow by using non-metallic,
non-conducting gaskets, sleeves, and washers.
2. Insulating flanges shall be suitable for oil and gas service at the pipeline design pressure and
temperature, and at the hydrostatic test pressure.
3. Flanges shall be installed on pipelines near or at platform cellar deck level as accepted by
Purchaser. Insulating flange kits manufactured by approved vendors shall be used.
4. The complete flange and insulating gasket assembly shall be covered with a removable
fireproof insulating cover or blanket.
20.0
OFFSHORE INSTALLATION
20.1
Pipeline Alignment and Tolerances
1. Supplier shall install the pipelines along the route indicated on the project alignment drawings.
The lines shall be installed in a lane of ± 50 feet (15 m) maximum width, centered on the
designed pipeline alignments, except where noted on the alignment sheets.
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2. Supplier shall install the subsea structures (PLETs, SSIVs, anode sleds, etc.) within the
specified target centers established by Purchaser. Target boxes defined below are nominal and
shall be confirmed for each project on a case-by-case basis, in conjunction with the
appropriate engineering analysis.
a. PLET or pipeline laydown flange target box shall be no more than ± 6.6 feet (2 m).
b. Subsea structure (PLET) tolerances shall be a maximum of ±1° from vertical at the hub
absolute vertical axis, or as determined by connector manufacturer.
c. Riser or pipeline transition piece target box shall be ± 20 feet (6 m).
d. Manifold target box shall be ± 6.6 feet (2 m).
e. Anode sleds target box shall be ± 6.6 feet (2 m).
f.
Suction pile target box shall be ± 3 feet (1 m) (± 1 degree vertical).
3. Installation Supplier shall ensure by design that PLETs land in accordance within these
tolerances and do not sink into the seabed by more than 4 inches (100 mm) after landing.
20.2
Installation
1. Mobilization shall include the assembly and transportation to the job site by Supplier of the
necessary construction personnel, equipment, machinery, tool supplies, and material.
2. Demobilization shall include disbanding and removal of personnel, equipment, machinery,
tools, supplies, and material from the offshore construction location after entire work scope is
completed.
20.2.1 Pipe Joint Recording
1. Supplier shall maintain a continuous record of each pipe joint incorporated into the
pipeline, and shall log the following:
a. Manufacturer’s unique joint number.
b. Joint updated length.
c. Date when the joint is welded and laid.
2. Supplier shall maintain a record of cut-outs and weld repairs, and shall amend joint
lengths accordingly in the records. All cut-outs, weld repairs, and tie-ins shall be
documented offshore on individual sheets that provide information on revised joint
length, placement, repairs, etc.
3. Joints of the pipeline shall be sequentially numbered. Using a suitable quick-curing
marine paint, white numerals 8 inches (203 mm) tall by 1 inch (25 mm) in thickness
shall be painted on each pipe length near the welded joint between the 10 o’clock and
the 2 o’clock positions.
4. Pipe tracking system shall maintain records of weld numbers, pipe numbers, pipe
lengths, cumulative lengths, anode installations, and repair numbers.
5. Vertical stripes visible by the ROV shall be applied periodically to pipeline at
specified spacing dictated by Purchaser, to help determine the rotation of the pipeline
during installation.
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20.2.2 Anodes Sleds
Note
This section defines the minimum requirements in the event that the CP design
dictates that the pipeline be cathodically protected by utilizing a few strategically
placed anode “sleds” rather than the more traditional “bracelet” anodes.
1. The installed pipeline shall be fitted with two sets of three CP bonding cables during
installation.
a. Cables shall be approximately 50 feet (15 m) long.
b. Each set of cables shall be positioned around the pipeline at approximately
120-degree spacing. This ensures that regardless of the orientation of the pipeline
after installation, at least two of the cables shall be accessible at all times.
c. Cables shall be secured along the pipeline in a manner that prevents them from
being disconnected during installation. However, the cables shall be attached so
that an ROV can disconnect them from the pipeline and transfer the free end to the
anode sled for connection.
d. Cables shall be fitted with a connector that is proven ROV friendly and that
provides a secure and reliable electrical connection between the pipeline and the
anode sled.
e. A minimum of two cables shall be successfully connected between the pipeline
and the anode sled. (To be successful, the cables shall be securely fastened to both
the sled and the pipeline, and there shall be electrical continuity between the
pipeline and the anode sled along each cable.)
2. After installation, the continuity of each connection shall be confirmed by Supplier to
satisfaction of Purchaser.
20.2.3 Welding and Weld Repair
Supplier shall perform all pipe joint line-up and welding in accordance with
SSM-SU-5003.
20.2.4 Installation Operations
1. Supplier shall take adequate precautions and shall provide the means to install the
pipeline on the seabed without damaging the pipe or its coating, or any other
structures or devices.
2. Supplier shall obtain weather reports specific to the location every 12 hours and shall
provide copies to Purchaser’s representative.
3. Supplier shall obtain current profiles specific to the location of the entire water
column every 12 hours and shall provide copies to Purchaser’s representative.
4. Within the procedure, a tension range shall be specified that will be adhered to during
all phases of pipeline installation. Tension range shall be accepted by Purchaser before
issuing Supplier authorization to mobilize to work site.
5. Operation outside of the accepted tension range shall not be allowed and shall be
grounds for Purchaser representative to demand suspension of installation operations
until tension can be brought within the accepted range.
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6. During installation, fatigue damage to the pipe shall be minimized to 10 percent of the
allowable fatigue damage unless specified otherwise in the project technical
requirement.
a. If pipelay is halted for an extended time period, the pipeline shall be paid out
periodically in order to eliminate excessive fatigue damage at a point on the pipe.
b. Details regarding possible fatigue damage to the pipeline shall be investigated
during up-front engineering, and guidelines shall be set forth in the contingency
procedures regarding how to handle fatigue situations.
c. Supplier shall perform fatigue analyses to determine the maximum installation
vessel standby time based on the allowable fatigue damage for relevant
environmental conditions.
7. Purchaser reserves the right to suspend pipelaying if malfunction or breakdown of
Supplier’s equipment occurs persistently. Pipelaying shall resume when equipment
has been adequately repaired or modified to the satisfaction of Purchaser.
8. Just before welding, lengths of pipe shall be internally cleaned by a method accepted
by Purchaser to remove dirt and loose rust. Just before alignment for welding, beveled
surfaces shall be cleaned by methods submitted to and accepted by Purchaser.
9. Open ends of the pipe shall be securely closed if work is interrupted, and shall not be
opened until work is resumed.
20.3
Pull Tube Operation
1. Supplier shall provide properly sized equipment for pull-in operations. Tensile forces in the
cable and chain shall be monitored and continuously recorded, using a Purchaser-accepted
load cell (with up to date calibration and certifications).
2. Purchaser shall specify the maximum force allowed for pull tube, due to platform limitations.
Supplier shall not exceed force specified by Purchaser.
3. The pulling location shall be selected to prevent the pull tube cable and chain from contacting
any member of the platform or other foreign items, except for the designated sheaves. The
location of sheaves and stringing of cable shall be accepted by Purchaser.
4. Upon completion of the riser installation, electrical isolation (0.010 volts) shall be confirmed
between the riser and platform or structure by Supplier using Purchaser-accepted equipment
and procedures.
5. All records of the riser and platform or structure potential measurements shall be provided by
Purchaser.
20.3.1 Planning
1. Supplier shall prepare and document procedures for installation of riser pipe, flexible,
and umbilical in each specified pull tube.
2. These procedures shall be submitted for Purchaser review and acceptance. Procedures
shall thoroughly describe the following aspects of the pull tube pull operation:
a. Barge position.
b. Anchor spread.
c. Barge and stinger configuration.
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d. Rigging.
e. Pull tube plug removal.
f.
Pull cable threading.
g. Platform protective measure.
h. Detailed stress calculations and pull force calculations.
3. Deviations from the accepted procedures shall not be permitted without prior consent
of Purchaser.
4. Supplier’s project engineer, barge superintendent, or rigging foreman shall accompany
Purchaser inspector in surveying the platform structure and pull tube orientation
before mobilization of the lay barge.
a. This visit shall establish the safest and most effective means of rigging up for the
pull tube, including attachment of blocks, cable routing, and hold-back cables.
b. Supplier shall provide all rigging material necessary for the performance of the
pull tube pull, including steel plate skids and other protective measures placed on
the platform.
5. Pull tube pull may be made using either platform-mounted or barge-mounted pull
winch or chain jack. In either case, the pull winch shall be capable of providing a pull
equal to at least 150 percent of the anticipated maximum pull force.
6. Pull tube pull shall be monitored by Supplier to provide the following:
a. Pull tube pull force during the entire pull tube pull.
b. Visual monitoring of the pull tube pull head by ROV as it enters the bellmouth of
the pull tube conduit.
c. Visual monitoring of the pipe string by ROV as it enters the bellmouth of the pull
tube conduit.
d. Visual monitoring of the pull tube seating plug as it is seated in the pull tube
bellmouth.
20.3.2 Pull Tube Conduit Plugs and Messenger Cables
1. The pull tube may be sealed and void of seawater. If sealed, the following shall apply:
a. Supplier shall flood the pull tube with seawater before removing the pull tube
plug.
b. After flooding, Supplier shall pressurize the pull tube with water, nitrogen, or
compressed air in accordance with the pull tube pump-out-plug manufacturer’s
recommendations.
c. It is possible that the pull tube plug will not be unseated at the anticipated
pressure; if so, Supplier shall use rigging and pressurization equipment capable of
pressurizing the pull tube to a minimum of 300 psig (20 barg).
2. If a messenger cable is used to thread the pull cable through the pull tube, Supplier
shall ensure that excessive tension is not applied to the messenger cable, in order to
avoid severing the cable.
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20.3.3 Pull Tube Appurtenances
1. Supplier shall fabricate a two-piece upper pull tube clamp and shall provide
attachment material. The clamp shall be installed around the pipeline, flexible, or
umbilical riser at the top of the pull tube before the pull cable tension is released.
2. Purchaser, as an option, may require that a special Splashtron elastomer-coated pipe
joint that incorporates a pull tube annulus plug be installed at the end of the riser pipe
string. If it is required, Purchaser and Supplier shall agree on the tension that will be
applied to seat the plug and on the amount of lead pipe to be placed in front of the
plug.
20.4
Holiday Detection
1. 100 percent of the pipeline corrosion coating, including all repair areas, shall be continuously
electrically inspected for holidays using a calibrated, Purchaser-accepted holiday detector that
employs both audible and visual signaling devices.
2. Inspection voltage shall be 125 volts per mil (volts/mil) based on the nominal coating
thickness.
3. Holiday detector calibration shall be checked and the output calibrated to the proper test
voltage once per 12-hour shift.
20.5
Abandonment and Recovery
1. Supplier shall provide an A&R procedure to Purchaser as part of the installation manual. This
procedure shall apply if weather or seas of sufficient magnitude, or the malfunction of major
equipment, endangers safe installation operations.
2. Supplier shall abandon the pipeline only in cases where it is absolutely necessary to prevent
damage to the pipeline. In abandonment, Supplier shall securely seal the pipe end in a manner
acceptable to Purchaser, to ready the pipeline to be lowered to the seabed.
3. Supplier may elect to partially abandon or completely abandon the pipeline at discretion;
however, any partial abandonment procedure shall be designed so the pipeline can be
completely abandoned as a continuation of the partial abandonment operation.
4. Abandonment procedures shall identify the circumstances under which Supplier intends to
completely or partially abandon the pipeline or riser to avoid high lay stresses, while keeping
the vessel connected to the pipeline with the abandonment cable.
5. Supplier shall mark the abandoned lines with transponders or other means in the event that the
abandonment or recovery cable is released from the installation vessel.
6. Immediately following the return of favorable weather conditions or satisfactory equipment
repairs, recovery operations shall be executed using procedures accepted by Purchaser.
a. Purchaser’s representative aboard the installation vessel shall be notified before the
beginning of any abandonment or recovery operations.
b. Pipe stress or strain limits as defined in Table 4 or Table 5 shall not be exceeded during
abandonment or recovery, and shall be verified by proper analysis during procedure
development.
7. Laydown heads shall be hydrotested to 1.25 times the maximum external pressure expected,
to ensure there is no unexpected leak path.
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20.6
SSM-SU-5297.1
Pickup and Laydown
1. If lifting or laydown of the pipeline or riser ends is required, pipe stress and strain limits as
defined in Table 4 or Table 5 shall not be exceeded during these operations.
2. If applicable, welding connections shall be made in accordance with project welding
specification.
3. Pipeline and riser pickups and laydowns for alignment purposes shall be done before the
hydrotesting of the line, and shall not be done without authorization from Purchaser.
20.7
Buckle Initiation
20.7.1 Sleepers
1. If sleepers are needed to provide buckle initiation points along the pipeline route,
Supplier shall be aware of the additional requirement to position the pipeline during
pipelay to an accuracy that ensures that the pipeline passes over the pre-installed
sleepers.
2. Sleepers shall be positioned approximately perpendicular to the pipeline route.
Supplier shall provide all necessary equipment to ensure that the pipeline is placed in
the center of the sleeper.
3. Visual monitoring of the sleepers shall be conducted until the pipeline installation has
extended to a position where there is sufficient anchor length of pipe on the seabed.
20.7.2 Buoyancy
1. If buoyancy devices are attached to the pipeline to provide buckle initiation points
along the pipeline route, Supplier shall be aware of the additional requirement to
attach sufficient buoyancy modules over sections of the pipeline to ensure the pipeline
section is buoyant.
2. Supplier shall provide all necessary equipment and personnel to ensure the buoyancy
can be attached to the pipeline, and the installed pipeline is using Supplier’s proposed
installation method.
3. Supplier shall use calibrated tools to properly secure the buoyancy modules to the
pipeline.
20.8
Protection of Nearby Existing Structures
1. Supplier shall take all necessary precautions, including the installation of temporary
underpinnings, supports, and other protective devices, to minimize the possibility of damage
to structures and pipelines in the vicinity of the installation area.
2.
A detailed report of damages and other incidents relating to structures, pipelines, umbilical,
and any part of the subsea architecture shall be prepared immediately for Purchaser.
3. If damage occurs during construction, repairs to the facilities shall be made at Supplier’s
expense, under the direction and to the satisfaction of Purchaser and third party whose
equipment was damaged.
20.9
Pipeline Spanning
1. If an unsupported span exists, visual evidence of it, such as videotapes, shall be made both
before and after remedial action has been taken by Supplier.
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2. Supplier shall develop installation procedures and shall control installation operations
(pipelay tension) to minimize possible on-bottom spanning.
3. For the proposed alignment, Supplier shall identify areas of potential pipeline spanning, and
shall perform pipeline spanning analysis for the area where pipeline spans could occur.
a. Supplier shall identify those areas to Purchaser with proposed means to minimize or
eliminate the spans by controlling installation.
b. Liquid traps or low spots on the final pipeline configuration shall be minimized.
4. Results of the analysis shall be submitted to Purchaser no later than 120 days before scheduled
start of pipeline installation.
5. After installation, but before flooding, the pipeline shall be surveyed for on-bottom spans. For
those spans that exceed the allowable lengths, Supplier shall perform span rectification, as
directed by Purchaser.
6. Pipeline installation manual shall detail how unsupported spans are to be located, measured,
and remediated.
20.10 Acceptance Testing
1. The pipeline and riser system shall be flooded, cleaned, gauged, and hydrotested in accordance
with project specifications.
a. Final hydrotesting shall be done after the pipeline is installed.
b. If the pipeline is picked up and moved for any reason before operation, acceptance testing
shall be performed again.
2. If the pipeline fails hydrostatic testing, Supplier, with Purchaser’s concurrence on procedure,
shall conduct search, find, and repair operations. Upon completion of the repair, the line shall
be re-hydrotested.
3. Supplier shall bear the costs due to such inferior workmanship or defective material furnished
by Supplier, including the cost of the re-test.
4. Procedures for accounting for charges associated with repairs shall be established in advance
with Purchaser’s representative.
20.11 Touchdown Monitoring
1. During pipelay, Supplier shall visually monitor touchdown at all times using an ROV.
a. If the ROV is unable to monitor touchdown, Supplier shall halt the pipelay operation.
b. Supplier shall continue only if Purchaser provides written authorization to continue
operations.
2. If the ROV is working from a vessel other than the main pipelay vessel, a video telemetry
system shall be installed to transmit the ROV video signal to the pipelay vessel. This system
shall be capable of transmitting a clear continuous video signal.
20.12 Subsea Structures Installations
1. During installation of subsea structures, Supplier shall monitor the position of the structure at
all times using an ROV.
2. Positioning equipment shall be provided by Supplier as necessary to ensure correct and precise
positioning of the subsea equipment.
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21.0
SHALLOW WATER INSTALLATION
21.1
General
SSM-SU-5297.1
1. Pipeline installation in shallow water shall be by one or more of the following methods:
a. S-Lay
b. J-lay
c. Reeling
d. Towing
2. Supplier shall submit for Purchaser review and acceptance detailed calculations and analysis
showing that the selected method(s) are acceptable for installation of the pipelines within the
scope.
3. Supplier shall perform static and dynamic analyses for pipelay, abandonment, and recovery at
least 60 days before mobilization.
4. Supplier shall compute, by methods acceptable to Purchaser, stresses to be expected during all
phases of operations.
a. Detailed calculations shall be performed using a three-dimensional, finite element
computer program such as OFFPIPE, OrcaFlex, PIPELAY, or a Purchaser-accepted
equivalent.
b. Environmental conditions and vessel motion shall be included in the analyses to determine
vessel workability.
c. For shallow water pipelines with concrete coating, the maximum stress during pipe
handling, shipping, storing, and during offshore pipeline and riser installation operations
shall not exceed the limits listed in Table 4.
5. Supplier shall submit a complete set of calculations that confirms that the installation stress
shall be maintained within the allowable limit.
a. Calculations shall show a plan and profile of the lay barge, stinger, and pipeline from the
bow of the barge to the TDP on the ocean floor.
b. Supplier shall specify the amount of tensioner dead-band to be used during pipelaying.
Table 4:
Pipeline Allowable Stress
Operation
Location
Pipeline Stress (% Specified
Minimum Yield Strength [SMYS])
Handling
Any
50
S-Lay
Overbend
85[1]
90[2]
Sagbend
72[1 & 2]
Notes:
1. Total applied bending stress (static) during pipelay operation.
2. Total applied bending stress (static and dynamic) during pipelay operation.
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21.2
SSM-SU-5297.1
Pipelaying
1. Vessel excursion limit analyses shall be provided.
2. Supplier shall provide to Purchaser for review and acceptance a pipelaying stress analysis for
the nominal tension, low dead-band tension, and high dead-band tension.
3. Stress control computations shall include parametric studies to determine laying operational
limits due to variations between the nominal and the actual field conditions. As a minimum,
considerations shall include the following:
a. Pipe wall thickness variations.
b. Weight coating thickness variations.
c. Weight coating density variations.
d. Stinger angle and depth variations.
e. Tension variations.
f.
WD variation.
g. Environmental condition directionality.
4. Supplier shall investigate stinger angle and depth variation to determine the lower and upper
attitudes of the stinger that lead to 85 percent of SMYS in the over-bend. The actual length of
pipe on the stinger during laying operations shall be expressly identified in Supplier’s
analyses.
a. Supplier shall investigate the effects of tension variation. A nominal or optimum vessel
tension and corresponding dead-band shall be selected by Supplier.
b. Nominal tension is that tension at the lay vessel tensioner(s) that satisfies the pipeline
stress, pipeline minimum route radius, and barge limitations, and the primary governing
parameters for selecting a nominal tension shall be the maximum pipeline sag-bend and
over-bend stresses.
c. Final nominal lay vessel tension (plus or minus the dead-band) shall satisfy all those
requirements mentioned and shall be less than the maximum available tension.
d. Supplier shall anticipate a minimum 10 percent variation of the nominal tension, i.e., a
dead-band of plus or minus 10 percent × T, where T is the nominal tension. As a
minimum, the matrix of combinations in Table 5 shall be investigated.
Table 5:
Pipeline Sensitivity Matrix
Tension (T)
Pipeline Weight (W)
Low dead-band
Nominal tension
Stinger (S)
Low attitude
Nominal weight
High dead-band
Nominal attitude
High attitude
5. Supplier shall carry out calculations for the following cases:
a. Case 1: T nominal, W nominal, S nominal
b. Case 2: T low, W nominal, S nominal
c. Case 3: T high, W nominal, S nominal
d. Case 4: T nominal, W nominal, S low
e. Case 5: T nominal, W nominal, S high
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6. Supplier shall investigate the effect of pipeline weight variation based upon the measured
weight of the purchased pipeline sections.
7. Supplier shall ensure that the maximum bottom lay tension is less than the design route radius
for all curved pipelines.
8. The factor of safety of the curve resistance to the bottom lay tension shall be a least 1.5.
Any deviations from this requirement shall be submitted for Purchaser review and acceptance.
9. Supplier shall perform analyses for pipeline laydown (abandonment) and recovery. Analyses
and results shall be submitted to Purchaser for acceptance.
10. Supplier shall perform analyses and prepare designs for pipeline repositioning, or for any other
procedure, for acceptance by Purchaser. The calculations shall account for any planned
horizontal movement of the line.
22.0
DEEPWATER INSTALLATION CONTROL
Each installation procedure and piece of installation equipment shall be developed and designed to
control installation of the pipeline within the limits established in this specification to eliminate
damage and avoid overstressing.
22.1
Allowable Strain
1. For deepwater pipeline without concrete coating and SCR, the maximum strain during pipe
handling, shipping, storing, and offshore pipeline and SCR installation operations shall not
exceed the limits listed in Table 6.
Table 6:
Pipeline Allowable Strain
Operation
Location
Pipeline and SCR
Strain (%)[1]
Handling
Any
0.10
Overbend [2 &3]
0.18
Sagbend
0.15
Within Tower [2]
0.18
Sagbend
0.15
S-Lay
J-Lay/Reel Lay [4]
Notes:
1. Total applied combined axial plus bending strain (static and dynamic) during
pipelay operation, including the elastic portion.
2. Within the tower and tensioners exit point.
3. For non-concrete coated pipeline in deeper waters, the overbend allowable strain
may be increased on a case-by-case basis upon Owner review and acceptance
of Purchaser proposal.
4. Refer to reel lay criteria after passing the straightener on the reel lay vessel.
Supplier shall provide the total cumulative strain during reeling and unreeling
for Purchaser review.
2. Installation procedures and supporting static and dynamic analyses shall demonstrate
conformance to the strain limitations shown in Table 6 along the entire route, with due
consideration for the following:
a. The effects of pipeline subsea structures (e.g., PLETs).
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b. Vessel offset envelope during lay, consistent with DP capabilities. Maximum offset shall
be established.
c. Anticipated range of tension variation (i.e., tensioner dead-band).
d. Stress and strain intensification due to stinger support reactions and effects of anodes,
buckle arrestors, and other items on the pipe.
e. Potential variation in the nominal submerged weight of pipeline and subsea structures
(PLETs).
f.
The effect of stern-on and beam-on currents and seas.
g. Allowable variation in stinger angle and stinger tip depth.
h. Stress and strain intensification due to (stiffer) in-line structure.
i.
Any other factor (e.g., stress intensification at field joints, bulkheads, buckle arrestors,
collar transition pieces, in-line structure, anodes, vessel excursions, and clamps) if the
factor causes significant changes in nominal pipe stress.
j.
Fatigue damage to the pipeline or riser.
3. Calculations to support conformance to the above limitations shall be based on static and
dynamic analyses, to ensure that the proposed installation procedures are not overstraining,
buckling, weakening, or damaging the pipeline and subsea structures (PLETs and in-line
sleds).
4. Supplier shall submit all analyses and calculations to Purchaser for review and acceptance.
22.2
Local Buckling and Ovalization
1. Notwithstanding the allowable strain limitations given in Section 22.0, Supplier shall ensure
that the combined effects of bending, tension, and external hydrostatic pressure during
installation do not subject the pipeline to a local buckling-type failure.
2. Local buckling analyses shall be based on accepted industry methods and shall consider an
initial pipe out-of-roundness and the additional expected ovalization induced by the
installation method.
3. For reel vessel installation, evidence shall be submitted to Purchaser with procedures,
documenting that the residual ovalization after being straightened does not represent potential
for buckling or other hazards to pipeline and riser.
22.3
Monitoring Pipelay
1. Control tower shall be able to monitor and adjust all pipelay equipment (e.g., winches and
tensioners).
2. Supplier shall continuously monitor and record the applied tension by each tension machine
during pipelay.
3. In addition, Supplier shall continuously monitor the pipe with adequate video cameras and
lights at suitable locations near the last support assembly as additional means to verify pipe
integrity for Purchaser acceptance.
4. Supplier shall have necessary spare equipment available on vessel to replace or repair
defective equipment as soon as is practical.
5. Video images shall be available in pipelay control room as well as other critical locations on
the vessel.
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SSM-SU-5297.1
MONITORING AND INSPECTION
1. Supplier shall develop an inspection matrix identifying hold, witness, monitor, and review
points for the onshore fabrication and offshore installation procedures. Purchaser shall review,
comment, and accept this document.
2. Purchaser shall be entitled to have representative, inspectors, or both present at any time
during the progress of work to be performed by Supplier. Supplier shall furnish free access to
any such work to Purchaser representatives at all times.
3. In the event work performed by Supplier is found to be unsatisfactory or not in accordance
with the contract drawings and specifications previously accepted by Purchaser, Supplier
shall, upon notice by representative or inspector, immediately revise such work in the manner
to conform to these specifications or drawings.
4. It is further agreed that in the event such revision is not promptly made, Purchaser may require
Supplier to suspend all work until revision has been made. Purchaser further reserves the right
to have an inspector available during process of shop fabrication of any material and
equipment to be furnished for the job.
23.1
Pipeline Welding and NDE
Welding, testing, and inspection of welds shall be performed in accordance with the following:
1. SSM-SU-5003
2. SSM-SU-54.14
23.2
Production Inspection and Testing
1. Supplier shall provide a manufacturing and test schedule. Schedule shall indicate all
significant manufacturing events, including the following:
a. Raw material order.
b. Material receipt.
c. Process start and finish dates.
d. Set-out.
e. Assembly.
f.
Testing.
2. Inspections and tests shall be completed before joint is welded into the pipeline.
3. Supplier shall furnish all material, equipment, and qualified personnel to perform the
inspections and testing specified herein.
4. Purchaser shall reserve the right to reject sections that do not meet the requirements of this
specification and referenced standards.
5. Replacement of rejected sections shall be at Supplier expense.
6. Supplier shall make available (i.e., within no more than 2–3 minutes walking distance) at each
of their fabrication sites a Purchaser representative office with phone for Purchaser’s own
business use, and fax and copy facilities readily available.
a. The office(s) shall each have adequate space, desks, and file cabinets for at least four
Purchaser representatives and inspectors.
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b. Supplier shall have adequate facilities available for Purchaser’s third-party NDE
personnel’s review of film.
c. Supplier shall establish a project team with a project engineer who will be the primary
contact between Supplier and Purchaser’s chief inspector.
23.3
Notification
1. Supplier shall notify Purchaser at least three weeks before commencement of production to
allow time for final acceptance by Purchaser of both the design and assembly procedure and
the inspection procedure.
2. After production has commended on the order, Supplier shall notify Purchaser’s representative
at least 24 hours in advance of any changes in the production schedule.
3. Supplier shall notify Purchaser at least 48 hours before any inspection or testing required by
this specification.
23.4
Purchaser Inspection
1. Purchaser representative will operate independently of Supplier inspectors and shall have free
entry at all reasonable times to areas of Supplier work or other associated facilities processing
these materials.
2. Purchaser reserves the right to witness all phases of assembly at Supplier’s assembly facility.
a. Purchaser also reserves the right to inspect the pipe at any stage of assembly to ensure that
they are manufactured in strict accordance with this specification.
b. Supplier shall provide Purchaser representatives all reasonable facilities.
3. Inspection by Purchaser representative shall in no way relieve Supplier of their responsibilities
for compliance with the specifications.
4. Purchaser representative shall be present whenever the pipe is cut or repaired.
23.5
Coating Inspection
1. During fabrication, spooling, and laying operations, Supplier shall inspect coated pipe for
damage to the coating before lowering the pipe into the water.
2. Coating shall also be inspected following an A&R procedure.
a. Coated pipe shall be inspected with a coil spring-type holiday detector per NACE SP0169,
in conjunction with the visual inspections.
b. Thermal insulation coated pipe shall be inspected visually per project specification.
3. Coating damage shall be repaired per accepted coatings repair procedures.
23.6
Subsea Inspection
1. Supplier shall have video monitoring (with DVD/DVR capability) at the tip of the lay ramp
during pipeline installation. Supplier shall present written procedures on the proposed methods
of inspection of the pipeline to Purchaser as part of the installation manual.
2. Supplier shall submit results and reports of all inspections to Purchaser in a timely manner
during installation, and shall include the results and reports as part of the as-built data.
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3. Supplier shall provide a final subsea inspection report for the pipelines that shall include at
least the following information:
a. Detailed plot(s) of the pipelines.
b. Condition and location of the subsea structures.
c. Condition of pipe coatings and sacrificial anodes, and location and description of damage
to same.
d. Description and location of debris or other objects that may affect the cathodic protection
system or otherwise harm the pipeline.
e. Video recording.
4. As-built records shall be presented in a record format that is bound and well tabbed.
A summary description of the design and physical characteristics, including the final
configuration, shall be presented.
5. The final report shall cross-reference reports previously submitted by Supplier so a continuity
of documentation is achieved. Video used as documentation shall be cross-referenced in
reports.
6. Originals of drawings and videos shall be submitted with the as-built report.
a. Each video shall be clearly marked with the contents of the video.
b. A catalog of the videos shall be submitted.
c. Videos shall be recorded in NTSC on either VHS or DVD (DVD is preferred).
23.7
Pipeline Spans
1. Before flooding, Supplier shall inspect for spans along the entire pipeline length.
a. Supplier survey shall be sufficient to locate and identify all possible pipe spans.
b. If the pipe span length exceeds the allowable free span length, appropriate measures shall
be taken to rectify the problem (e.g., the use of sand/cement bags, grout bags, soil, or
gravel backfill before flooding).
2. No span rectification shall be done without notification of Purchaser and authorization from its
representative. After the span rectification procedure has been completed, the pipeline and
supports (if applicable) shall be inspected for damage and surveyed to see if they have been
properly installed to the satisfaction of Purchaser.
3. Supplier shall provide detailed drawings of all spans. Each drawing shall include at least the
following information:
a. Pipeline name and dimension.
b. Number of joints or partial joints suspended.
c. Joint number(s).
d. Date survey was conducted.
e. Location (area, block number, coordinates).
f.
Reference video number.
g. Record of depth at pipeline TDP at each end of suspension.
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h. Record of total distance of suspended pipeline between TDPs. Record of depth from top of
pipeline to bottom at critical locations or at intervals specified by on-site Purchaser
representative.
i.
Horizontal distance of suspended pipeline between TDPs.
j.
Maximum vertical distance measured between the top of the pipeline and the bottom.
k. Minimum vertical distance measured between the top of the pipeline and the bottom.
l.
Record of the general visibility conditions in the area.
m. Record of the speed (estimated) and direction of bottom current in the area of the
suspension.
n. Record of a description of the bottom, i.e., hard or soft, clay or sand.
24.0
CROSSINGS OF FOREIGN PIPELINES
1. Purchaser shall provide the locations of known structures and foreign pipelines along the
proposed pipeline route, as determined by the route and hazard survey.
a. Responsibility for locating these structures, foreign pipelines, and cables shall rest with
Supplier.
b. Supplier shall use real-time positioning to locate each underwater facility to Purchaser’s
satisfaction before the pipelay vessel approaches such facility.
2. Where the pipeline route intersects other subsea pipelines, cables, or unavoidable underwater
geophysical structures, Supplier shall install specified support above the existing facility to
permit installation of the proposed line above the facility.
3. Supplier shall allow a minimum of 3 hours bottom time to locate existing pipelines at
crossings based on Purchaser-furnished approximate coordinates. Supplier shall provide a
magnetometer and shall perform an on-bottom circle-search of the proposed crossing area.
4. Supplier shall include a sufficient quantity of concrete mattresses or sand/cement bags for
installation at each crossing, in accordance with the contract drawings. For concrete
mattresses, non-abrasive pads shall be placed on surfaces that may contact new or existing
pipelines.
5. The lowering, dredging, and installation of supports, if required, shall be performed in
accordance with procedures prepared by Supplier and accepted by Purchaser.
6. Supplier shall provide suitable underwater video cameras to inspect the completed crossings.
a. Inspection shall be made in the presence of Purchaser representative and other interested
parties.
b. The work and inspection shall be performed to Purchaser satisfaction.
7. Supplier shall not lower existing pipelines without written authorization from both Purchaser
and owners or operators of existing pipelines.
8. Minimum clearance between existing and proposed lines shall be 18 inches (457 mm).
Sand/cement bags (3 parts sand to 1 part cement) or concrete mats shall be placed between
the 2 lines to maintain the separation.
9. Supplier shall provide the necessary facilities onboard the pipelay vessel for third-party
crossing representatives for whatever period of time is required to complete the crossing(s).
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10. Pipeline laying corridor shall be reduced to ± 13 feet (4 m) from 500 feet (152 m) before to
500 feet (152 m) after a pipeline crossing.
11. Video inspection of the ROV or diver visual inspection shall be performed to verify the
crossing was completed per requirements of this specification.
25.0
RIGHT-OF-WAY
1. Purchaser shall obtain necessary right-of-way easements and shall secure work permits
pertaining to the right-of-way from governmental agencies involved.
2. Supplier shall adhere to said right-of-way, as shown on drawings, and no changes or
adjustments shall be made by Supplier without prior acceptance of Purchaser.
3. Purchaser shall advise Supplier of right-of-way easement and permit provisions, and Supplier
shall agree to observe them. Purchaser shall obtain right of ingress and egress to the
right-of-way.
4. Supplier shall be responsible for all other permits necessary for the performance of this work.
These permits shall include, but not be limited to, the following:
a. Permits for moving of its vehicles and equipment.
b. Interruptions to navigation.
c. Additional work or storage space.
d. Work performed outside of right-of-way permit limits.
26.0
PIPELINE INSTALLATION MANUAL
Supplier shall prepare and issue as part of the pipeline installation manual descriptions and details
of the sections outlined in Table 7.
Table 7:
Sections of Pipeline Installation Manual
Section
Description
Pipe Tensioners
• Tensioner pad geometry.
• Maximum operating tension.
• Operations procedures including how dead-band is monitored and controlled.
Abandonment and
Recovery Winch
• Description of the abandonment and recovery winch.
• Maximum operating tension.
• Monitoring and control.
Davits
• Drawing showing all davit locations on the barge, and their functional
capacity.
Pipelay Initiation
• A description of the method(s) to be used for pipelay initiation for each
pipeline, for Purchaser acceptance.
• Detailed design calculations for Purchaser acceptance for connecting of
return sheaves at the bottom or top of any Purchaser jacket leg for pipelaying
initiation, or for any lay-away method from existing subsea equipment.
• Buoyancy requirement, winch capacity, and cable sizing.
• Calculations and drawings.
Pipelay Excursion for
DP Vessel
• Vessel watch circle graphs that depict maximum allowable vessel excursion
under different operating conditions, so that the allowable bending strains are
not exceeded and the pipelines are installed within the specified right-of-way.
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27.0
AS-BUILT DOCUMENTATION
27.1
General
SSM-SU-5297.1
1. Within 30 days after completion of pipeline lay, Supplier shall submit to Purchaser for
acceptance three copies of comprehensive bound and indexed welding “as-built”
documentation records.
2. All documentation shall be on 8.5 × 11-inch (A4) or 11 × 17-inch (A3) paper size. Documents
shall be presented in units noted in the project technical requirement. Supplier shall report in
multiple sets of units, with Metric or English units included.
3. As-built documentation shall include the following:
a. Daily job reports.
b. Tally sheets, in electronic data format.
c. Test reports.
d. Final QACP documents.
e. Drawings.
f.
Detailed report of the pipe ends cut.
g. NDE reports.
h. Final survey reports.
i.
Final configuration of the pipeline with results presented by means of as-built drawings.
j.
Inspection records.
k. Video/DVD tapes from ROV monitoring.
l.
Site queries and correspondence.
4. Pipeline coordinates on the as-built survey drawings shall be at a maximum interval of
500 feet (152 m) and at a scale in accordance with MMS regulations in the U.S.
Note
For other areas, refer to local regulations, project technical requirements, or both.
5. Survey notes shall be included.
a. Navigation for the survey shall use state-of-the-art positioning systems.
b. Minimum survey accuracy shall be DGPS system with a positional repeatability
of ± 6 feet (1.8 m).
6. Supplier shall provide pipeline coordinates, bottom of pipe elevation, and seabed profile data
at an adequate interval acceptable to Purchaser.
7. As-built survey drawings shall be subject to Purchaser review and acceptance.
8. As-built documentation shall be submitted as electronic records in Adobe Acrobat file format,
unless noted otherwise, on a CD-ROM disc or discs, as required.
a. CD-ROM file records shall be indexed with a brief explanation of each file directory and
file entry.
b. The index record shall be duplicated on each CD-ROM required to contain all records.
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9. On a daily basis while offshore, Supplier shall provide Purchaser with legible copies of QACP
documents and reports for review and comment. All QACP documentation generated offshore
shall be reviewed, accepted, and signed off by Purchaser representative offshore.
10. The data book records shall contain, as a minimum, the following information.
a. Weld procedure qualification records.
b. Weld procedure specifications.
c. Welder performance certificates.
d. Weld consumable certificates.
e. NDE procedure qualification records.
f.
NDE inspection reports.
g. NDE operator qualifications.
h. Weld production control records.
i.
Pipe assembly production records.
j.
Outgoing pipe tally.
k. All fabrication reports including the following:
1) Pipe cut reports.
2) Field joint coating reports.
3) Pipe fit-up reports.
11. On-site Purchaser representative will review all documentation. Supplier shall provide
documents for on-site representative on a daily or weekly basis, rather than providing all
documentation at the end of the job.
27.2
Video Requirements
1. The quality of the video survey shall be sufficient to allow conclusions to be drawn regarding
the structural integrity of the pipeline(s), coatings, and cathodic protection systems.
2. Every effort shall be made to produce high resolution, properly focused video documentation.
The quality of each video shall be checked upon changing tapes/disks.
3. Legible characters describing the pipeline attributes (e.g., size and location) shall be displayed
as a video overlay and recorded on video tape.
4. If during the as-built ROV survey any data acquisition equipment fails, survey operations will
cease until all equipment is repaired and fully functional and the survey will be resume from
the last recorded position fix with allowance for sufficient survey overlap.
5. Videos shall be numbered consecutively starting with number 1, shall be labeled AS-BUILT
SURVEY, and shall include pipeline designation and size, video number, and date.
6. The video portion of the survey shall include at least the following:
a. Fix position number.
b. Each exposed anode cable and general condition.
c. All locations with complete pipeline burial.
d. All pipeline crossings.
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e. All pipeline spans (with details of start/stop, etc.).
f.
All subsea equipment related to the pipeline (e.g., PLETs).
g. All anomalies in a close proximity to the pipeline.
h. Areas of unusual bottom topography.
i.
All damage to pipeline components.
7. Verbal introduction at the beginning of each tape and periodically during each tape shall
include the following:
a. Date.
b. Video number.
c. Brief subject of video.
d. Pipeline attributes (e.g., size and location).
e. Direction of travel.
f.
Start point (fix number or physical location on pipeline).
8. Include a brief verbal description of general condition of pipeline, coating system, anodes,
spans, crossings, and PLETs. Particular attention should be given to any damage or anything
unusual.
9. Verbally record position fix number at each fix location.
10. Time shall be recorded using real time as displayed on the video monitor.
11. A summary video log sheet shall be maintained that lists all video concerned with each
segment of the project.
12. All video logs will be reviewed and signed by the onboard Purchaser representative for
compliance with the requirements.
13. A concise summary video tape showing events or details of major importance will be edited
from the project video tapes, either during or immediately following conclusion of the work.
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APPENDIX A
ADDITIONAL REFERENCES
The following references are not cited in this specification but are listed here for further reference.
A.1
A.2
Purchaser Documents
COM-SU-202
Materials and Application of Painting and Protective Coatings
COM-SU-6095
Three-Layer Polypropylene Coating for Pipelines
FFS-PU-5116
Transportation of Cargo by Barge or Ship
FFS-DU-5407
Design of Suction Piles
PPL-SU-1050
Welded Line Pipe: Electric Welded and Submerged Arc Welded Line Pipe
PPL-SU-1051
Seamless Line Pipe
PPL-SU-1564
Radiographic Inspection
PPL-SU-2005
Concrete Coatings of Line Pipe—Compression Method
PPL-SU-2014
Concrete Coating of Line Pipe Impingement Method
PPL-SU-4737
Hot Induction and Cold Shop Bending
PPL-SU-5193
Pig Launcher and Receiver
PPL-SU-5252
Hydrotest Water Quality for Corrosion Prevention
SSM-SU-5404
Structural Materials and Fabrication
SSM-SU-5405
Longitudinal Submerged Arc Welded (SAWL) Line Pipe for Water Depths
1500 Feet and Greater
SSM-SU-5410
Design and Construction of Pipeline End Terminations (PLETS)
SSM-PU-5280
Loadout and Installation of Subsea Umbilicals
SSM-SU-5408
Seamless Line Pipe for Water Depths 1500 Feet and Greater
SSM-SU-6092
Welding and Fabrication of Subsea Equipment
Industry Codes and Standards
American Petroleum Institute (API)
RP 1111
Design, Construction, Operation, and Maintenance of Offshore
Hydrocarbon Pipelines (Limit State Design)
Spec 5L
Specification for Line Pipe
Spec 5LD
Specification for CRA Clad or Lined Steel Pipe
Spec 6A
Specification for Wellhead and Christmas Tree Equipment
American Society of Mechanical Engineers (ASME)
B16.2
Metallic Gaskets for Pipe Flanges—Ring-Joint, Spiral-Wound, and Jacketed
B16.5
Pipe Flanges and Flanged Fittings—NPS 1/2 Through NPS 24 Metric/Inch
Standard
B16.9
Factory-Made Wrought Buttwelding Fittings
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B16.47
Large Diameter Steel Flanges—NPS 26 through NPS 60 Metric/Inch
Standard
B31.4
Pipeline Transportation Systems for Liquid Hydrocarbons and Other
Liquids
B31.8
Gas Transmission and Distribution Piping Systems
American Welding Society (AWS)
D1.1/D1.1M
Structural Welding Code – Steel
ASTM International (ASTM)
A105/A105M
Standard Specification for Carbon Steel Forgings for Piping Applications
A193/A193M
Standard Specification for Alloy-Steel and Stainless Steel Bolting for High
Temperature or High Pressure Service and Other Special Purpose
Applications
A194/A194M
Standard Specification for Carbon and Alloy Steel Nuts for Bolts for High
Pressure or High Temperature Service, or Both
A694/A694M
Standard Specification for Carbon and Alloy Steel Forgings for Pipe
Flanges, Fittings, Valves, and Parts for High-Pressure Transmission Service
A707/A707M
Standard Specification for Forged Carbon and Alloy Steel Flanges for
Low-Temperature Service
E8/E8M
Standard Test Methods for Tension Testing of Metallic Materials
Det Norske Veritas (DNV)
OSS-302
Offshore Riser Systems
RP-F103
Cathodic Protection of Submarine Pipelines by Galvanic Anodes
International Maritime Organization (IMO)
Maritime Safety Committee (MSC)/Circular 645
Guidelines for Vessels with Dynamic Positioning Systems
International Marine Contractors Association (IMCA)
D 010
Diving Operations from Vessels Operating in Dynamically Positioned
Mode
M 103
Guidelines for the Design and Operation of Dynamically Positioned Vessels
M 117
The Training and Experience of Key DP Personnel
National Association of Corrosion Engineers (NACE)
MR0175/ISO 15156 Petroleum and natural gas industries—Materials for use in H2S-containing
environments in oil and gas production
RP 0394
Application, Performance, and Quality Control of Plant-Applied,
Fusion-Bonded Epoxy External Pipe Coating
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