DEVELOPMENT OF TINRHERT GAS FIELDS
TOWARDS ALRAR “FULL DEVELOPMENT”
EPC2 – LOT1
CONSTRUCTION OF SEPARATION AND DECARBONATION UNITS AT ALRAR
PETROFAC PROJECT NO. : JI-2050
CONTRACT NO : CT-EPC/009/SH/EPM-E&P-G/2022
PIPING DESIGN SPECIFICATION
THIS DOCUMENT IS PREPARED
BASED ON
FEED SPECIFICATION FOR
PIPING DESIGN SPECIFICATION
116Z-TRHT-ST-P-0000001, REV. B
0
24-MAR-23
B
22-FEB-23
A
07-DEC-22
Rev
Date
ISSUED FOR
DESIGN
RE-ISSUED FOR
APPROVAL
ISSUED FOR
APPROVAL
MSR
SCS / CVJ
KM / DS
JSK / RL
MSR
SCS / CVJ
KM / DS
JSK / RL
RK
SCS / CVJ
KM / DS
JSK / RL
Reason for Issue
Prepared By
Checked By
Approved by
Project
Approval
Project No
Plant
Identifier
Document Type
Discipline
Code
System
Number
Equipment
Type
Sequence
No
Rev.
22009
TRHT
SP
PI
00
OO
401
0
PIPING DESIGN SPECIFICATION
22009-TRHT-SP-PI-00-OO-401, REV 0
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REVISION HISTORY
Rev.
Section
Description of Revision
A
-
Issued for Approval
B
-
CA comments incorporated
0
-
CA comments incorporated
HOLDS
Rev.
Section
Description of Hold
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Table of Contents
1.0
INTRODUCTION ................................................................................................6
1.1 PROJECT DESCRIPTION
6
1.2 OVERALL DESCRIPTION OF TINRHERT DEVELOPMENT
7
1.3 NEW FACILITIES TO BE INSTALLED IN TINRHERT ALRAR CPF8
1.4 ORDER OF PRECEDENCE
9
1.5 DEFINITIONS
9
1.6 TERMINOLOGY
10
2.0
OBJECT ...........................................................................................................10
3.0
RESPONSIBILITY ............................................................................................10
4.0
UNITS SYSTEM ...............................................................................................10
5.0
TECHNICAL DOCUMENTATION FOR REFERENCES ..................................11
6.0
BASIS OF PIPING DESIGN .............................................................................12
7.0
6.1 GENERAL
12
6.2 PIPING DESIGN CRITERIA
14
PLOT PLAN AND PIPING LAYOUT ................................................................16
7.1 CRITERIA OF DISTANCES AND SPACINGS BETWEEN UNITS 17
7.2 ROAD AND ACCESSWAY CLEARANCE
17
7.3 ACCESSIBILITY AND MAINTENANCE
18
7.4 MAINTENANCE
20
8.0
PIPING PUMPS ................................................................................................21
9.0
SAFETY VALVE ...............................................................................................22
10.0
PIPE CLASSIFICATION...................................................................................22
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11.0
PIPE SUPPORTS .............................................................................................23
12.0
STRESS ANALYSIS ACTIVITIES....................................................................23
13.0
MATERIAL TAKE-OFF ....................................................................................23
14.0
U/G PIPING ......................................................................................................24
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ABBREVIATIONS:
CPF
Central Processing Facility
AGRU
Acid Gas Removal Unit
FEED
Front End Engineering Design
BOP
Bottom of Pipe
FGL
Finished Grade Level
P&ID
Process & Instrumentation Diagram
HSE
Health, Safety and Environment
MTO
Material Take-Off
MR
Material Requisition
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1.0 INTRODUCTION
1.1
PROJECT DESCRIPTION
SONATRACH has decided to develop the TINRHERT fields with its own resources. These fields are
in South-Eastern Algeria within the Wilaya of Illizi.
The geographic position of these fields is indicated on the map below.
Figure 1: Geographic position map of the Tinrhert Fields
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The development of these fields is intended for an additional hydrocarbon contribution to the facilities
indicated below:

Ohanet CPF

Alrar CPF

Stah CPFs
1.2 OVERALL DESCRIPTION OF TINRHERT DEVELOPMENT
The development of the Tinrhert fields is divided in four (4) lots as follows:

Lot 1:
o
Gathering network for the North fields to the Ohanet CPF.
o
Gathering network for the South fields to the Alrar CPF.
o
Surface installations at the wellhead for the gas wells to be connected in the short term phase
(twenty-six (26) wells to Ohanet CPF and twenty (20) to Alrar CPF)

Lot 2:
o
Surface installations at the wellhead for the gas wells to be connected in the medium term
phase (twenty three (23) wells) and in the long term phases (twenty three (23) wells).
o

New facilities beside of Ohanet CPF.
Lot 3:
o
Surface installations at the wellhead for twenty six (26) wells and their connection to the
gathering network
o
Gathering network and the electrical multiphase pumps stations needed for the Oil ring wells to
the existing HP Inlet Separator train at Stah CPF
o
New compression unit at Stah CPF (3x50%) to handle the gas from new oil ring production
only
o
Gas export line from new compression unit at Stah CPF to Alrar CPF
o
New electrical overhead lines to the pumps stations.
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
Lot 4:
o
Surface installations at the wellhead for the wells to be connected in the medium term phase
(sixty-two (62) wells) and in the long term phase (sixteen (16) wells).
o
New facilities beside of Alrar CPF.
1.3 NEW FACILITIES TO BE INSTALLED IN TINRHERT ALRAR CPF
The development of the South fields of Tinrhert deposits destined for the Alrar CPF required the
installation of the following facilities besides the existing Alrar CPF:

New arrival manifolds to CPF

Equipment for receiving and separating the raw gas from fields south of Tinrhert (Inlet separation)

Acid Gas Removal unit (AGRU)

Construction of new utilities

The Electrical network

A processing unit to treat the produced water

Water Injection unit to inject the treated water in water injection well
The raw gas will come separated to the Devonian and Ordovician separators and the flows will be
joined downstream of the inlet separators. The production will be sent to the inlet or outlet of the
existing Boosting Compressor depending on the pressure available in the gathering System. New
Acid gas removal units will be located downstream of the existing Boosting trains.
The hydrocarbon condensate separated in the inlet separation facilities will be sent to the existing
condensate treatment trains.
The produced water separated in the inlet separation facilities will be sent to the new water treatment
plant, from where, the treated water will be sent to the reinjection system to be injected in the water
disposal wells.
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1.4 ORDER OF PRECEDENCE
The following is the order of precedence for the CONTRACT documentation
a) The Contract
b) Algerian statutory requirements
c) Contracting Authority documents
d) Project Design Basis
e) All other Contracting Authority Technical Data
f) FEED ITB package documents
g) International codes, standards and specifications
1.5
DEFINITIONS
For the purpose of this document, the following definitions apply:
CONTRACTING
SONATRACH SPA Engineering & Project Management
AUTHORITY OR “CA”
(EPM)
CONTRACTOR
Le Groupement (non immatriculé) de Petrofac International
(UAE) LLC et GCB SpA
The party(s) which manufactures and / or supplies materials,
SUPPLIER / VENDOR
equipment, technical documents / drawings and services to
perform the duties specified by PURCHASER.
PROJECT
DEVELOPPEMENT DES CHAMPS GAZIERS DE
INRHERT VERS ALRAR « FULL DEVELOPMENT » EPC2
LOT 1 : REALISATION DES UNITES DE
SEPARATION ET DECARBONATATION A ALRAR ,
ALGERIE
DPEM
Direction des Patrimoines Energétiques et Miniers (Algerian
Ministry of Energy and Mines)
L’Agence Nationale de Contrôle et de Régulation des
ARH
Activités dans le domaine des Hydrocarbures (Agency for
Regulation of Hydrocarbons)
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1.6
ONML
Office National de Métrologie Légale
CTC
Contróle technique de la construction
TERMINOLOGY
The words “shall” and “must” is to be understood as a mandatory requirement.
The word “should” is to be understood as strongly recommended.
The words “may” and “can” is to be understood as an action to be undertaken at the Contractor’s
discretion.
2.0 OBJECT
This specification constitutes the basic requirements, guides, rules and methods to be used during
piping design & plant layout for the Tinrhert Fields Development EPC2 Lot1 Construction of
Separation and Decarbonation Units at Alrar. All criteria defined in this specification are general but
not mandatory; applicable Codes and good engineering practice and judgment shall prevail when
related to specific systems.
3.0 RESPONSIBILITY
The Piping Department Manager or the delegated Piping Lead Engineer shall be responsible for the
contents of this specification and for verification of its compliance with all relevant specifications and
codes.
4.0 UNITS SYSTEM
Unless otherwise stated, the International System of Units shall be used, except for nominal diameters
of pipe and fittings, which shall be expressed in inches.
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5.0 TECHNICAL DOCUMENTATION FOR REFERENCES
Latest editions of below listed international codes and standards prevailing as on 21st July 2022 shall
apply. The new facilities also shall be designed in accordance with Algerian Laws and Legislation,
Company standards and Project specifications.
API STANDARDS
- API RP 520
Sizing, Selection and Installation of Pressure Relieving Devices in
Refineries.
- API 610
Centrifugal Pumps for Petroleum, Petrochemical industries.
ASME STANDARDS
- ASME B31.3
Process Piping.
- ASME B16.5
Steel Pipe Flanges and Flanged Fittings NPS ½ through NPS 24
- ASME B16.47
Large Diameter Steel Flanges: NPS 26 through NPS 60
Metric/Inch standard
- ASME B36.19M
Stainless Steel Pipe
- ASME B36.10M
Welded and Seamless Wrought Steel Pipe.
- ASME B 1.1
Unified Inch Screw Treads (UN &UNR Tread Form).
- ASME B1.20.1
Pipe Threads, General Purpose.
- ASME B16.9
Factory made Wrought Steel butt welding fitting.
- ASME B16.10
Face to face and end to end dimensions of valves.
- ASME B16.11
Forged Fittings, Socket welding and threaded.
- ASME B16.20
Metallic Gasket for Pipe Flanges – Ring Joint, Spiral Wound and
Jacketed.
- ASME B16.21
Non-metallic Flat Gaskets for Pipe Flanges
- ASME B16.25
Butt Welding ends for pipe, valves, flanged &fittings.
- ASME B16.34
Valves - Flanged, threaded & welding ends.
- ASME B18.2.1
Square and Hexagonal bolts and Screws.
- ASME B18.2.2
Square and Hexagonal Nuts.
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OTHERS
For Control Valve dimension standards & rating refer to General Instrument Specification and
Control valve specification
PROJECT SPECIFICATIONS
22009-TRHT-SP-PI-00-OO-404
Process Basis of Design
22009-TRHT-SP-PI-00-OO-408
Piping Stress Analysis Specification
22009-TRHT-SP-PI-00-OO-409
Pipe Support Specification
22009-TRHT-SP-MT-00-OO-403
Painting and Coating Specification
22009-TRHT-SP-MT-00-OO-406
Insulation Specification
22009-TRHT-TB-CV-00-OO-401
Civil & Structural Design Basis
22009-TRHT-AE-PI-00-OO-401
3D CAD Modelling Procedure
22009-TRHT-AE-PI-00-OO-402
3D Model Review Procedure
22009-TRHT-TP-XA-00-OO-405
Fire Fighting System Philosophy
22009-TRHT-SP-IN-00-OO-401
General Instrument specification
22009-TRHT-TB-PR-00-OO-401
Process Basis of Design
6.0 BASIS OF PIPING DESIGN
This document along with the Codes and Standards listed constitutes the basic documents, guides,
rules and methods to be used for the piping design for Tinrhert Fields Development EPC2 Lot 1
Construction of Separation and Decarbonation Units.
6.1 GENERAL
Piping must always be designed by taking the following criteria into consideration:
- PROCESS: The design must meet process and operation requirements and follow a logical flow
sequence when it comes to piping and plant layout. The number and the attributes of the piping
system shall be as indicated in the corresponding P&ID, while the Project Line list shall indicate
particular service and design conditions for each piping system for example, operating and design
conditions, paint and insulation requirements etc.,
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- SAFETY: The safety of the plant, plant personnel and third parties shall be ensured by adherence
to, the relevant safety standards, codes and recommendations developed for the project and
observed by means of Risk, Hazard and Operability (HAZOP) analysis.
In addition, all appropriate access and escape ways shall be provided for.
- OPERATION AND MAINTENANCE ACCESS
The design shall enable suitable access to the equipment, valves, instruments and manholes for
facility operation and/or maintenance.
- SPECIFIC REQUIREMENTS, STANDARDS AND SPECIFICATIONS
That which is stipulated in international and local codes and standards, as well as specific Company
specifications and/or requirements that have been agreed and laid down in the Project shall all be
complied with.
- STRESS
The design must be sufficiently flexible in order to prevent excessive stresses on the pipes, equipment
nozzles and/or flange leakage due to thermal expansion and contraction. The complete range of
temperatures to which the piping may be subject shall be taken into account, as must the effects of
design condition operating, emergency, start-up, shutdown and test conditions. Special attention shall
be paid to the design of piping systems connected to critical equipment given their particular influence
on the process or their operating conditions. (For details refer Piping Stress Analysis Specification,
Doc. No. 22009-TRHT-SP-PI-00-OO-408)
- COMMON DESIGN PRACTICES
Good engineering practices shall be followed when designing piping with respect to plant layout and
design, line, routings, setting out of piping elevations, piping layout around equipment, etc.
- COST
All piping shall be laid in order to achieve an economic design, while at the same time comply with all
the afore mentioned criteria, bearing in mind the shortest routing possible and requiring the minimum
amount of fittings in such a way as to save time, material, and the costs associated with the
construction and operation of the plant.
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- CONSTRUCTION FACILITY: The design shall take into account all available construction facilities
during the piping fabrication, transportation and equipment/piping erection stage.
6.2 PIPING DESIGN CRITERIA

All lines within the battery limits and between processing units shall be aligned on a common
bottom of pipe (BOP) for uninsulated pipe inside pipe racks, or bottom of pipe shoe for
insulated lines. When necessary, changes of direction shall be accompanied by a change of
elevation.

Piping shall not be run diagonally, except where diagonal runs offer substantial savings or are
required for layout reasons.

Specific elevations shall be selected for lines running North-South and other specific
elevations for those running East-West. These elevations shall be used throughout the unit,
except where pockets must be avoided.

The bearing plate shall be installed between pipes (SS, DSS) and structure, sleeper and
support with 3 mm of thickness also welded from four sides.

For future piping on racks, Pipe bridges and sleepers, a free space of 20% shall be left
unoccupied.

In pipe racks, the small pipe diameter shall be intermixed with the large pipe diameter, so that
the small diameter pipe can be supported by the large diameter pipe to avoid numerous
intermediate pipe supports.

All pipes shall drop out of racks 900 mm from rack column centerline as a minimum and with a
common back of pipe or underside of shoe.

Butt-welded elbows shall be long radius type 1.5 D.

Pipes shall lie on sleepers or steel supports. The lines will be in piping trays or elevated pipe
supports, with a common BOP or – for insulated lines – underside of pipe.

The minimum height of piers or concrete sleepers shall be 500 mm from FGL if there is a drain
connection in that line else minimum height shall be 300 mm from FGL.

The
minimum
distance
between
welds
is
in
accordance
with
figure
shown
below
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
All pipe, fittings and valves shall confirm to the piping material specification for the services
specified on the Piping drawings, Isometrics, Pipe fabrication spool drawings, Line schedule
etc. Pipe diameters of NPS 1-1/4, 2-1/2, 3-1/2, 5, 7, 9 and 22 shall not be used

Reducer at pump suctions shall be eccentric with the flat side up

All piping specification break in one piping system shall be executed as flanged connections.
In case a break is for same material such as carbon steel and carbon steel, a flange
connection is not required.

Emergency shutdown valves, process control valves, self-regulating valve etc., shall be
located to provide ready access on at least one side.

In pipe racks, pipe bridges and sleepers there shall be 50mm clearance minimum between the
outside of pipe or insulation and any flange on adjacent piping. Exceptions to this minimum
requirement due to stress considerations, anti-vibration guidelines, limited space available etc.
shall only be allowed with the express approval of Company.
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
All slope requirements for piping shall be as reflected in the P & ID's.

With regards to the pipe slope, the slope refers to the horizontal plane.

Lines will be designed to avoid pockets of gas or liquid; where this is not possible, vents and
drains shall be installed at high and low points in the system respectively.

Unless stated otherwise, the minimum pipe size allowed shall be no less than 1/2” diameter.
However, on Pipe rack and on Sleepers the minimum pipe size shall be 2”.

Reductions in horizontal lines shall be made generally through eccentric reducers; in vertical
lines, concentric should be used. The maximum allowable reduction shall be a size smaller
than half the nominal diameter unless otherwise specified in applicable codes and standard.

The elevations will be referred to the axis of the pipe or the BOP whenever indicated.
7.0 PLOT PLAN AND PIPING LAYOUT
For existing plants, a plot plan will be developed based on the latest revision of the existing plant.
The plot plans produced in the FEED equivalent phase will be subject to review during the early
stages of detailed engineering to ensure they fully reflect the design basis.
Plot plans and equipment layouts shall include multidiscipline input to optimize them with respect to
issues such as:
- Emergency exits and assembly point.
- Extend of the plot along with co-ordinates, north direction and grade elevations
- Fence and gates as applicable
- Layout of roads (main and secondary)
- Equipment and their location
- Pipe rack and sleepers
- Buildings and shelters
- Laydown / maintenance areas
- Storm water drain trench
- Process flow direction.
- Safety (gas release, H2S, fires, etc.) and safe distances between equipment.
- Prevailing wind direction.
- Location of flare and offsite facilities.
- Accessibility and ease of operation and maintenance and escape routes.
- Vicinity of existing facilities.
- Environmental impact.
- Ease of construction, especially future works.
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- Potential future expansion
The new facilities will be connected to the existing plants, with the connections between units
documented in the Project Tie-in list.
The minimum height for the equipment foundations and the Pipe support foundations, the Civil &
Structural design basis shall be followed (Doc. No.: 22009-TRHT-TB_CV-00-OO-401)
7.1 CRITERIA OF DISTANCES AND SPACINGS BETWEEN UNITS
The criteria of minimum distance separation between units or marked systems are based on access
and security-related charges (see Summary table of minimum distances between units document
22009-TRHT-TP-HS-00-OO-401 HSE DESIGN PHILOSOPHY)
Deviations from these criteria may be permitted on the basis of the integration of new equipment, or
process reasons.
These adjustments shall not affect the safety of installations and operating personnel.
7.2
ROAD AND ACCESSWAY CLEARANCE
Inside the new facilities, roads will be planned around each unit and on the outskirts of the plant.
Access routes to equipment, buildings and structures shall have sufficient vertical and horizontal
clearance for firefighting, operation and maintenance.
6m wide roads must withstand loads of 12 tons per axle.
Access ways to equipment, buildings and various structures shall be 4 m wide minimum.
- Clearance above access road shall be 5.5m height minimum
- The recommended personnel access widths are as follows:
Criteria
Primary Escape Route (*)
Secondary Escape Route(**)
Horizontal Clearance
Headroom Clearance
1200mm
900mm
2200mm
Operational Access Way
800mm
Access stairs on Tank
750mm
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(*) Allow for primary escape route: typically on the perimeter and centre of the facility, which lead
directly to muster points.
(**) Allow for Secondary Escape Route: typically leading to a primary route
Wherever possible the access ways for fire- vehicles will be free from overhead structures and must
not cross obstacles.
Access for firefighting vehicles must not end in dead ends.
7.3 ACCESSIBILITY AND MAINTENANCE
Piping shall be arranged to allow access for operation and maintenance to all equipment.
For items that require frequent access for operation and maintenance but are not readily accessible
from grade, access platforms shall be provided. In general:
- Platforms are required:
On pipe racks where valves (manual, actuated ON / OFF, Relief valves and control valves) require
operation and maintenance
On vertical and horizontal vessels
Around safety, control and motorized valves, actuated ON / OFF valves and any items requiring
frequent operation and maintenance
At Air Coolers
At Furnaces
Permanent platform will be considered for valves that require frequent access for operation and
maintenance if the valve height exceeds 1.6 m from grade or platform.
If permanent platform is not possible due to layout constraint, mobile platform shall be considered.
- Ladders can be used:
as a means of escape
where infrequent operating access is required
at restricted operating areas
- Stairs are the preferred means of access:
for platforms
for emergency escape
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All control valves and actuated ON / OFF valves shall be accessible from ground level or from
permanent platforms; valves shall be placed in horizontal lines. Actuator orientation shall typically be
vertical for control valves and ON/OFF valves, however may change depending on the application.
Access shall be provided for hand wheel and control panel mounted on the actuator for actuated ON /
OFF valves and control valves, wherever applicable.

Platforms shall be provided at all elevated equipment and controls that are beyond reach from
grade for manual operation and maintenance. When horizontal exchangers and condensers
are located in groups, the platform shall be continuous.

Handrails shall be provided on all open sides of platforms and walkways which are 500 mm or
more above adjacent floor or ground level.

At air coolers, platforms shall be provided to facilitate access to fans, motors and gearboxes
for maintenance and removal. If there are several air coolers grouped together the platforms
shall be combined.

Platforms shall be provided at the transition piece of multi-sized stacked vessels so that the
ladders will be kept in a vertical position. However, where the upper section of the vessel is
smaller in diameter than the lower section, a maximum slope of 15 degrees from the vertical
will be permitted.

Manways, with their axis (center line) elevation above 3600 mm above grade, shall be
provided with platform.

Platforms with ladder shall be provided on battery limits, in order to facilitate operation of
valves, instruments and the rotation of blinds.

Removable sections of handrail shall be provided for exchanger bundle removal or any other
equipment requiring space for removal.

Ladders shall have a constant slope from platform to platform, or to grade. Ladders shall be
used as primary access to platforms attached to vessels and to auxiliary service platforms.

On vertical ladders not equipped with cages, the horizontal distance from the centerline of the
rungs to the nearest permanent object on the climbing side of ladder shall not be less than 750
mm. A clear width of at least 375 mm shall be provided each way from the centerline of the
ladder in the climbing space.

Side step ladders shall be used. Double side step ladders at the same elevation are not
permitted; minimum difference in elevation between two platforms serviced by the same ladder
shall be 600 mm. Step through ladders without platforms are not permitted.
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
Ladders should not be oriented facing open spaces; they should be oriented facing walls or
equipment.

All indicating Instruments and Instruments requiring adjustments shall be adjustable for
servicing from floor levels, walkways, platforms and ladders. A mobile platform / permanent
platform shall be considered if the access height of valve exceeds 1.6m.
Orifice plates,
temperature elements etc., may be accessed by temporary means provided they are less than
3 metres above the floor level. Above 3 metres they shall be provided with permanent access.

Minimum straight run requirements of pipe upstream and downstream of flow orifices shall be
followed as per applicable Instrument standard requirements.

Orifices shall be installed in horizontal lines wherever possible. If installed in vertical lines, flow
shall be upward for liquids and downward for gases. Vertical line installation shall be avoided.

The minimum pipe size for thermowell installation is 4”. Piping smaller than 4” NB shall be
locally swaged up to 4” NB. Minimum pipe size shall be checked with Instrumentation if the
thermowell size is 2”. Location, orientation and accessibility of thermowells shall take account
of the withdrawal space required for the instrument.
The stairways are required in accordance with the criteria below:

Where process, inspection and maintenance operations are required daily.

Where exposure to hazards from acids, gases and the like may be possible.

For access to platforms around groups of vessels and other equipment located adjacent to
each other.
Stairs shall not be less than 900 mm wide between handrails and shall be clear of any obstructions,
except in the case of handrails attached to walls.
7.4 MAINTENANCE
The Piping designers shall take into account the maintenance operations for different equipment,
considering the vendors recommendations and below criteria:

Where mobile cranes are required to approach process equipment for regular maintenance,
piping and structures shall be arranged so as not to cause obstruction.

Manway covers shall be hinged or equipped with handling davits. Hinge shall be located so
that manway closes in the direction of escape way.

Access shall be provided for portable bundle pullers used for servicing channel and tube
bundles of tubular units
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
Exchanger piping and pipe supports shall be located so that they do not interfere with the
removal of channel covers and tube bundles when mobile lifting equipment is used.

Orientation of davits and manways shall be such that:
o Internals removed through manways are accessible for lifting by davit.
o Drop-out areas provided at the tower are accessible for mobile equipment.

In case of extraordinary maintenance activities, provisions for removable sections of walls or
roofs enclosing such equipment shall be considered according to manufacturer instructions.

Where bolt tensioning equipment shall be used, adequate clearance shall be provided around
flanged connections for installation and operation of the bolt tensioners.
8.0 PIPING PUMPS
Pumps shall be adequately supported to minimize the stress on the pump during operation and also
to allow the disassembly of equipment; the piping layout shall ensure sufficient clearance space
above, in front, behind the pumps and space for electrical junction box and the push button operation
and maintenance.
Pump piping shall contain removable spools to permit disassembly of conical strainers; removable
spools are not required, not necessary for permanent strainers.
Permanent filters will be type “T” or “Y”, according to the nominal pipe size and specification, with the
piping connections in accordance with the line class ratings per the piping specification
Suction lines will be drained through a drain located at the lower point of the pump housing
discharging to the drainage system, as indicated on the P & ID's.
Piping design should include the following design criteria.
• Wherever practicable pumps shall be arranged in rows with the centre line of the discharge
nozzle on a common straight line.
• For end suction pump, elbows shall not be directly connected to the suction flange.
• Pump discharge check valve, if installed in vertical lines shall be fitted with a drain
connection as close as possible downstream of the valve.
• Piping shall be arranged that the forces and moments imposed on the pump nozzle do not
exceed the allowable values/ manufacturer's recommendation.
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9.0
SAFETY VALVE
Relief piping shall be adequately supported to protect against the thrust effect of the discharging
medium.
The nominal size of the inlet pipe is equal to or greater than the size of the inlet flange of the safety
valve.
Safety valves that discharge to a closed system are positioned at the level of the collector on a
platform.
The discharge pipe of a safety valve which discharges to a recovery system will be self-draining to a
relief header.
All flare collectors have the slope indicated in P&ID’s; if this slope is not practical, a lesser slope may
be used upon approval by Company.
Any increases in the diameter of a flare header shall be made using bottom-flat eccentric reducers.
The discharge flare connections shall be made at 45º to the flow direction and preferably from the top
of the pipe; where top branch connections are not feasible, side connections at 45º are permissible;
however, branch connections from below the horizontal are not permitted. Also, 90° tapping will be
considered according to layout requirement and Stress analysis,
Relief piping shall be adequately supported to protect against the thrust effect of the discharging
medium.
For hydrocarbon relief piping discharging to atmosphere, the valves shall be located at the high point
with the vent line terminating 3m above the highest operating platform within a radius of 15 m of the
point of discharge; for gas, the minimum discharge height above ground shall be 6m subject to
confirmation of vent dispersion study and 2m for water vapour.
Drains will be provided for low point in vent lines, discharging to a safe place.
10.0 PIPE CLASSIFICATION
The Pipe classification is based on design pressure and temperatures that can be considered as a
simultaneously-occurring condition and is used for the selection, metallurgy of components, types of
flanges and valves, wall thicknesses.
The various operating and design temperature and pressures are reflected in the Project Line List.
The piping material classes specification (see document 22009-TRHT-SP-PI-00-OO-404) defines the
pressure and temperature service limits, material class, corrosion range and pipe wall thickness for
each individual pipe class.
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11.0 PIPE SUPPORTS
There are three categories of pipe supports as detailed below:
Standard pipe supports
Common detailed pipe supports are detailed in Standard pipe support specification, doc. No. 22009TRHT-SP-PI-00-OO-409). These supports are placed by the pipe support designer.
Engineered pipe supports
These are pipe supports structures specifically designed for the duty; the supports are located and
identified by the pipe support designer, but become part of the civil ’s deliverable.
Special pipe supports
These are individual pipe supports that may be built up from common pipe supports or an engineered
support and may include a special nonstandard item. Each special pipe support shall have its own
data sheet and drawing “SPECIAL PIPING SUPPORTS”
12.0 STRESS ANALYSIS ACTIVITIES
“Piping Stress Analysis Specification” will be developed to define the criteria and guidelines required
for the stress analysis of all the piping systems in order to ensure appropriate flexibility and
compliance with the requirements established in applicable codes, standards, reference
documentation and specific Company conditions relevant for this project. Mentioned specification will
define in detail the critical lines that should be analyzed during detailed engineering using CAESAR II
computer software, the maximum allowable stress in the piping systems, the loads (sustained,
thermals, occasional…) to be considered in the calculations and in general the methodology to carry
out the stress analysis.
This specification also describes the content of the corresponding stress dossier each critical piping
system to be issued during detailed engineering with all the relevant information obtained from the
calculation. Refer Piping analysis specification, Doc. No. 22009-TRHT-SP-PI-00-OO-408
13.0 MATERIAL TAKE-OFF
The Materials Take-Offs (MTOs) and the preparation of the Material Requisitions (MRs) of the piping
bulk materials, valves and special piping items in such a scheduled way as to ensure the timely flow of
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materials to fabrication shops and Field shall be carried out by the piping material department in
cooperation with other Disciplines.
Based on preliminary P&IDs and piping layout, and piping documents, the Material department shall
generate a preliminary piping material take-off (MTO) to provide input for cost estimates, stating the
relevant margins.
The MTO will be provided as a spreadsheet showing number of line, service, piping class, material
identification code, insulation and painting material - if required - and spare parts if applicable.
14.0 U/G PIPING
Buried metallic piping shall have a minimum cover of soil as follows:
• In Areas accessible to traffic - 0.9 m.
• In Areas inaccessible to traffic – 0.6 m.
For buried non-metallic piping, the minimum cover of soil shall be as per vendor recommendation.
Buried piping passing under roads with soil cover less than that specified above shall pass through
pipe sleeves or concrete duct banks / culverts.
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