PIPING SYSTEM
CODES
A code gives guidelines about the subject.It tells
rejection and acceptance part of it. EX: ASME
SEC VIII DIV 1
Standards is for specific product and gives
guarantee for quality of that product. EX: ANSI B
16.5
Regulations
rules.EX:IBR
are
government
imposed
PRESSURE PIPING CODES B 31
B 31.1 POWER PIPING.
Piping typical found in electric power generation stations, in
industrial and institutional plants, geothermal heating systems, and
central and district heating and cooling systems,
B 31.3 PROCESS PIPING.
Piping typically found in petroleum refineries chemical,
pharmaceutical , textile , paper semiconductor , and cryogenic
plants, and related processing plant and terminals,
B 31.4 PIPELINE TRANSPORTATION SYSTEMS FOR
LIQUID HYDROCARBONS AND OTHER LIQUID .
Transporting products, which are predominately liquid between
plants and terminal and within terminals, pumping ,and metering
stations.
B 31.5 REFRIGERATION PIPING.
Piping for refrigeration and secondary coolants.
B 31.8 GAS TRANSPORTATION AND DISTRIBUTION
PIPING SYSTEMS.
Piping transporting product which are predominately gas between
sources and terminals.including compressor, regulating,and metering
station, and gas gathering pipelines,
B 31.9 BUILDING SERVICES PIPING.
Piping typically found in industrial ,institutional,commercials,and
public building and in multi-unit residences
B 31.11 SLURRY TRANSPORTATION PIPING SYSTEM
Piping transporting aqueous slurries between plants and terminal,and
within terminal and within terminal, pumping, and regulating stations.
SCOPE OF B31.3
a) This Code prescribes requirements for Materials and components,
design, fabrication, assembly, erection, examination, inspection,
and testing of piping.
b) This code applies to piping for all fluids, including:
1) Raw, intermediate, and finished chemicals;
2) Petroleum products;
3) Gas, steam, air, and water;
4) Fluidized solids;
5) Refrigerants;
6) Cryogenic fluids (-151o to –425oF).
EXCLUSIONS OF B31.3
This code excludes following:
•
Piping systems design for internal gauge pressures at or
above zero but less than 105kPa (15psi), provided the
fluid handled is nonflammable, nontoxic, and not
damaging to human tissue and its design temperature is
from –29oC (-20oF) through 186oC (366oF);
•
Power boiler s in accordance with BPV code Section-I
and boiler external piping which is required to confirm
to B31.1
•
Tubes, tube headers, crossovers, and manifolds of fired
heaters, which are internal to the heater enclosure; and
•
Pressure vessels, heat exchangers, pumps, compressors,
and other fluid handling or processing equipment,
including internal piping and connections for external
piping.
DESIGN PRESSURE
The design pressure of each component in a piping system shall be
not less than the pressure at the most severe condition of coincident
internal or external pressure (Minimum or Maximum) expected
during service
DESIGN TEMPERATURE
The design temperature or each component in a piping system is the
coincident temperature,under the coincident pressure, the greatest
thickness or highest component rating is required.
MINIMUM TEMPERATURE
The design minimum temperature is the lowest component
temperature expected in service.
FLUID CATEGORY ON B 31.3
CATEGORY D
A) The fluid handled is non flammable,non toxic ,and not damaging to
human tissues.
B) The design gauge pressure does not exceed 150 Psi and
temperature is from –29 c to 186 c.
C) Example water,air.(testing of the system not stringent.)
CATEGORY M
A fluid service in which the potential for personnel exposure is judged
to be significant and in which a single exposure to a very small
quantity of a toxic fluid,caused by leakage,can produce serious
irreversible harm to persons on breathing or bodily contact, even
when prompt restorative measures are taken.
Example .H2 SO4, CL2 Gas (Thread flanges are not recommended. Low
pressure testing is also one of the requirement.
HIGH PRESSURE FLUID SERVICE –K CATEGORY
If the pressure is in excess of 2500 rating for specified design
temperature and material group.
NORMAL FLUID SERVICE.
A fluid service pertaining to most piping covered by this code ie not
subject to the rules for category D,category M or high pressure fluid
service.
PIPE UNDER INTERNAL PRESSURE
•
For t<D/6, the internal pressure design thickness for straight pipe
shall be not less than that calculated below
t=
PD
2(SE + PY)
•
The minimum thickness T for the pipe selected, considering
manufacturer’s minus tolerance, shall be not less than tm..
tm = t + c
Where,
tm = minimum required thickness including mechanical,
corrosion, and erosion allowances.
t = pressure design thickness
PIPE UNDER INTERNAL PRESSURE
c = the sum of the mechanical allowance plus
corrosion and erosion allowances.
T = Pipe wall thickness
P = internal design gauge pressure
D = outside diameter of the pipe
E = quality factor from Table A-1A or A-1B
S = stress value for material form Table A-1
Y = Coefficient from Table 304.1.1, valid for t < D/6
and for material shown. The value of Y may be
interpolated for intermediated temperatures.
THICKNESS OF PIPE BEND
The minimum required thickness tm of a bend, after bending, in its
finished form, shall be determined in accordance with Eq.(3c) :
t=
PD
(3c)
2[(SE/I) + (PY)]
Where at the intrados (inside the bend radius)
I = 4(R1/D) – 1
(3d)
4(R1/D) – 2
and at the extrados (outside bend radius)
I = 4(R1/D) + 1
(3e)
4(R1/D) + 2
and at sidewall on the bend centerline radius, I = 1.0
R1 = bend radius of welding elbow or pipe bend .
THICKNESS OF BLIND FLANGE
The minimum required thickness of a permanent blank shall
be calculated in accordance with Eq. (15).
tm = dg√(3P/16SE) + c
(15)
Where,
dg = inside diameter of gasket for raised or flat face
flanges, or the gasket pitch diameter for ring joint and fully
retained gasketed flanges
E = quality factor from Table A-1A or A-1B
P = design gauge pressure
S = stress value of material from Table A-1
c = sum of allowances
IMPACT TESTING
For carbon steels, impact testing exemption is given in fig
323.2.2a of B31.3.If a design minimum metal
temperature-thickness combination is on or above the
curve, impact testing is not required.
NPS- A dimension less designator of pipe .It indicates standard pipe
size when followed by the specific size designation number with out
an inch symbol (eg NPS 2, NPS 12)
NORMALISING- A process in which a ferrous metal is heated to a
suitable temperature above the transformation range and is
subsequently cooled in still air at room temperature.
POST HEATING- The application of heat to a fabricated or welded
section subsequent to a fabrication, welding or cutting operation. Post
heating ,or the entire assembly may be post heated in a furnace.
POST WELD HEAT TREATMENT- Any heat treatment subsequent
to welding.
PREHEATING- The application of heat to a base metal immediately
prior to a welding or cutting operation.
Galvanizing – A process by which the surface of iron or steel is
covered with a layer of zinc
PREHEATING
Preheating is used, along with heat treatment, to
minimize the detrimental effects of high temperature and
severer thermal gradients inherent in welding.
Requirement and recommendations : Required and
recommended minimum preheat temperatures for materials
of various P-Numbers are given in table. If the ambient
temperature is below 0oC (32oF), the recommendation
become requirements.
Preheat Zone : Preheat zone shall extend at least 25mm
(1in.) beyond each edge of the weld.
HEAT TREATMENT
Heat treatment is used to avert or relieve the
detrimental effects of high temperature and severe
temperature gradients inherent in welding, and to relieve
residual stresses created by bending and forming.
Governing thickness : When components are joined by
welding, the thickness to be used in applying the heat
treatment provisions of Table 331.1.1 shall be that of the
thicker component measured at the joint.
BLOCK DIAGRAM OF DETAILED ENGINEERING
BID DOCUMENT
PRE-ENGINEERING
SURVEY
EQUIPMENT
LAYOUT
ISOMETRIC DRAWINGS
FABRICATION
DRAWINGS
FABRICATION
DRAWINGS
PIPING GENERAL
ARRANGEMENT
PIPE SUPPORT
GAD
PIPE SUPPORT
PRE-CONSTRUCTION SURVEY
INSTALLATION
MATERIAL TAKE OFF
PURCHASE
SPECIFICATION
PROCESS FLOW DIAGRAM (PFD)
- BLOCK DIAGRAM SHOWS UNIT OPERATIONS AND
UNIT PROCESSES INVOLVED.
-SHOWS ALL MAJOR EQUIPMENT AND MAIN PIPING
AND ITS FLOW. BASED ON THIS PROCESS FLOW
DIAGRAM ENGINEER PREPARES PIPING &
INSTRUMENTION DIAGRAM.
PIG
•Device that moves through the inside of a pipeline for
the purpose of cleaning .
NEED OF PIG A PIPELINE:
• Remove any debris left in the line from the new
construction
• To maintain line efficiency
•Types of pigs
1) cleaning pigs:equipped with wire brushes or blades
to do the cleaning
2) sealing pigs:used during hydrostatic testing of
pipelines
LAUNCHER & RECIEVER
•Pig launchers are used to launch the pig into the
pipeline & receiver to receive pigs after
they have made successful run
•Shall be installed horizontally with 5° slope in
the direction of flow
•Internal dia of launcher/receiver shall be atleast
2” higher than the pipe dia
•F.B valves on launcher/receiver must be round
•All distribution/collection header shall have their
dead ends blind flange
SCRAPPER TEE
•Purpose of scrapper tee is not to allow passage of pipe
scrapper / pig on to the branch pipe.
•Consists of concentric barrel tees
•Suitable for pigging operation with process
hydrocarbon/raw sea water
•Inside dia shall be same as that of inside dia of riser to
maintain smooth pigging operation.
•Maximum opening shall be provided through slots to
limit the pressure drop.
•Total opening shall be 1 to 1.5 times branch pipe area
FLANGE
BRANCH
PIPE
SOCKOLET
PIG DETECTOR
SCRAPPER TEE
TYPICAL SCHEMATIC OF PROCESS LINE.
SERVICE.
HEADER.
GAS TO VENT HEADER.
LIFT GAS.
VENT HEADER.
SERVICE
HEADER.
GAS
TEST
SEPERATOR.
OIL
+
WATER
+
GAS
PRODUCTION MANIFOLD.
CRUDE OIL MIXTURE
(OIL+WATER+GAS)
OIL WELL
WATER DISCHARGE TO SEA.
CRUDE
CONDENSATE DRUM.
PIPE
SEPERATOR.
CI
CHRISTMAS
TREE.
OIL MIXTURE
FROM
DRAIN.
GAS FROM
SERVICE GAS HEADER.
HEAT EXCHANGER.
HEATED GAS
TO CONSUMER
LINES.
LAUNCHER
CI
TO PROCESS
PLATFORM
(OIL+WATER+GAS)
PIPING & INSTRUMENTATION
DIAGRAM
THIS IS A DETAILED DIAGRAM WHICH IS DEVELOPED
BASED ON PROCESS FLOW DIAGRAM. IN THIS
DIAGRAM ONE WILL COME TO KNOW ABOUT THE
EXACT NUMBER OF FLUID SERVICES INVOLVED
APART FROM MAIN PROCESS FLUID. ALSO THIS
DIAGRAM WILL HELP PIPING ENGINEER IN
DEVELOPING HIS PIPING ARRANGEMENT.
THE INFORMATION WHICH THIS DIAGRAM WILL
PROVIDE TO PIPING IS
- CONNECTING POINTS OF THE PIPE
-SIZE OF PIPE
- MATERIAL CLASS OF PIPE
- FLUID SERVICE OF THE PIPE
- UNIQUE LINE IDENTIFICATION NUMBER
- INSULATION
- CONNECTING POINTS OF A PIPE
-VALVES, INSTRUMENTS AND SPECIALITIES INVOLVED
IN
THE PIPELINE.
- PRESSURE, TEMPERATURE FOR THE EQUIPMENTS.
-ALWAYS A P&ID IS ACCOMPANIED WITH LEGEND P&ID
IN WHICH ALL SYMBOLS (USED IN P&ID) ARE
EXPLAINED.
LINE NUMBER DESIGNATION –
1.5”-DH-A1N-1129SIZE
LINE NUMBER
FLUID SERVICE
MATERIAL CLASS
LINE LIST
PROVIDES SUMMARY OF ALL PROCESS
PARAMETERS OF SYSTEM. IT IS PREPARED FROM
P&ID.
PROVIDES INFORMATION ON :
-
LINE NUMBER
- FLUID IN SYSTEM SERVICE CLASS
- HEAT TRACING
PAINTING
- LINE SIZE
FLUID PHASE
OPERATING & DESIGN PRESSURE , TEMPERATURES
STRESS RELIEVING REQUIREMENT
RADIOGRAPHY REQUIREMENT
PWHT REQUIREMENT
TEST FLUID & TEST PRESSURE
INSULATION REQUIREMENT
LINE LIST
EQUIPMENT LAYOUT
THIS DIAGRAM INDICATES THE POSITION OF
EQUIPMENT IN THE PLANT. ALL EQUIPMENTS ARE
LOCATED WITH THEIR CO-ORDINATES OR THEY ARE
LOCATED FROM GRID REFERENCE POINTS. FOR EACH
EQUIPMENT ITS TAG NUMBER IS ATTACHED. THIS
DRAWING IS PREPARED BY PIPING ENGINEER WITH
THE HELP OF PROCESS ENGINEER
PIPING ENGINEER FURTHER DEVELOPS HIS GENERAL
ARRANGMENT DIAGRAM BASED ON THIS.
PIPING GENERAL ARRANGEMENT
DIAGRAM
THIS DIAGRAM SHOWS THE ROUTING OF PIPE AS
PER THE P&ID WITH RESPECT TO EQUIPMENT
AND EXISTING STRUCTURE.
INFORMATION
PROVIDED :
- EQUIPMENT LOCATION & ORIENTATION
- LINES WITH LINE NUMBERS
- INSTRUMENT TAG
- ROUTING OF PIPE BETWEEN EQUIPMENTS
- LOCATION OF EXISTING EQUIPMENT &
INTERCONNECTING PIPING
- ELEVATION OF PIPE LINES
PIPING SUPPORT GAD
- SHOWS TYPES OF SUPPORT AND THEIR
LOCATIONS IN THE PIPE LINE
- REFER STANDARD PIPE SUPPORT SKETCHES GIVEN BY CONSULTANT
- THERE CAN BE SPECIAL TYPE OF SUPPORTS
ALSO.
ISOMETRIC DRAWING
LINE DIAGRAM OF PIPING, SHOWS FOLLOWING :
- Operating and Design temperature
- Operating and Design pressure
- Insulation required
- Thermal tracing
- Hydro test pressure
- Bill of material
- Inch-dia, Inch Meter
- Piping Class
- Pipe support locations
- Service of fluid
- Points of weld, its marking
- Pipe support type
Activities in ISO’S
1) Numbering of shop joint & offshore joints in
successive numbers
2) Numbering of spool according to the individual spools
3) Check the BOM according to the item
no.,inch,schedule&description
4) According to the pipe size,the no.of shop,offshore
joints are added in the table inside the isometric.
5) Inch meter,inch dia is calculated
6) Inch meter =pipe length in meter x pipe size in inch
7) Inch dia =pipe size in inch x no.of joints
8) No.of spools are noted in the table
9) For the continuing sheets,the numbering of shop
joints,offshore & spool numbers will also be
continuous.
PIPE SUPPORTS
-
PROVIDE SUPPPORT SO THAT, PIPE DOES
NOT SAG OR BEND
-
SUPPORT LOCATIONS ARE IDENTIFIED AND
STRESS ANALYSIS OF PIPE IS UNDERTAKEN
-
SUPPORT LOCATION DEPENDS ON PIPE
DIAMETER AND THICKNESS
-
EXPANSION BELLOW FOR PIPE FOR WHICH
OPERATING TEMPERATURE IS HIGH
-
VARIOUS STANDARD SUPPORTS ARE AVAILABLE
-
THERE ARE SPECIAL SUPPORTS ALSO
MATERIAL TAKE OFF
- THIS DOCUMENTS GIVE THE TOTAL MATERIAL
REQUIREMENT FOR THE JOB WHICH INCLUDES
PIPES,
FITTING, FLANGES, GASKETS, FASTENERS, VALVES,
SPECIALITY ITEMS, STRUCTURES ETC.
- MAIN MTO FOR TOTAL JOB REQUIREMENT
- HYDRO - TEST MTO ( AT YARD, AT OFFSHORE )
- SPARES MTO (WHEN CLIENT REQUIRES)
- CONTINGENCIES CONSIDERED (DIFFERENT FOR
NEW BUILDING or REVAMP JOBS)
PRE – ENGG SURVEY
- FINALISE DATE OF SURVEY, TAKE CLIENT
PERMISSION & MAKE OFFSHORE PASS
- FORM THE TEAM WITH : INSTALLATION
CONTRACTOR, DESIGN CONSULTANT, MFF
MEMBERS
- CARRY OFFSHORE SCOPE OF WORK, DESIGN
STANDARD, CHECK LIST – FOR SURVEY
- CARRY OUT SURVEY & COLLECT ALL
RELEVANT DATA
- CHECK LIFTING CAPACITY OF EXISTING DECK
CRANE & MONO RAIL
- CHECK IF EXISTING EQUIPMENT HAS TO BE
DISMANTLED TO TAKE OUT
PRE – ENGG SURVEY
- CHECK, IF BREAK – DOWN AREA IS NEEDED
- CHECK, IF ANY STRUCTURAL MEMBER IS TO
BE CUT TO TAKE OUT AN EUQIPMENT
- CHECK IF TUGGER LINE / PAD EYE IS NEEDED
TO BE USED TO LIFT OR SHIFT WEIGHT
- CONSIDER APPROACH OF BARGE OR SUPPLY
VESSEL TO REQUIRED LOCATION WITH LOAD
- ON COMPLETION OF SURVEY, INSTALLATION
CONTRACTOR / DESIGN CONSULTANT IS TO MAKE
A PRE- ENGG SURVEY REPORT
PRE – ENGG SURVEY
- SUBMIT REPORT TO CLIENT FOR INFORMATION
AND TO SHOW MISMATCH, IF ANY, BETWEEN
ACTUAL & BID – PACKAGE DATA.
- NEGOTIATE WITH CLIENT FOR EXTRA COST &
TIME (IF SOME WORK IS TO BE DONE OUT OF
SCOPE)
- DECIDE THE ACTIVITIES FOR PRE-SHUT-DOWN,
SHUT-DOWN AND POST-SHUT-DOWN PERIOD, IN
DISCUSSION WITH INSTALLATION CONTRACTOR
AND ONGC PLATFORM PEOPLE.
PRELIMINARY DATA FROM
DESIGN CONSULTANT
- IN GENERAL, A DESIGN CONSULTANT IS
EMPLOYED FOR BASIC & DETAILED
ENGINEERING
- CONSULTANT REVISES P & ID (REFER NEXT
SHEET) & GAD, MAKES ISOMETRICS, PREPARES
STRESS ANALYSIS REPROT, PIPE SUPPORT
DRAWINGS & STRUCTURAL DRAWINGS BASED
ON SURVEY DATA
- ALL DOCUMENTS ARE SUBMITTED TO CLIENT /
CLIENT’S CONSULTANT FOR THEIR APPROVAL
- FIRST MTO IS MADE & CHECKED BY MFF ENGG
PERSONNEL, USE THIS MTO FOR ORDERING.
PRE – INSTALLATION SURVEY
- DURING THIS SURVEY, REVISED DRAWINGS ARE
CHECKED WITH EXISTING CONDITION ON
PLATFORM ONCE AGAIN.
- CHECK FOLLOWING :
- DIMENSIONS
- FEASIBILITY OF CONSTRUCTION
- HOOK- UP POINTS
- EASE OF INSTALLATION
- ANY OTHER POINTS - MISSED EARLIER
PRE – INSTALLATION SURVEY
- A PRE - INSTALLATION REPORT IS MADE BY
INSTALLATION CONTRACTOR
- ISSUES LIKE SHUT-DOWN REQUIREMENT AND
MARINE SPREAD ARE HIGHLIGHTED
- REPORT IS SUBMITTED TO CLIENT FOR
APPROVAL
- IF NECESSARY, MTO IS REVISED AGAIN
MARKING OF SHOP JOINTS
Shop joints are the welding joint done at shop. For
joining pipe to pipe, pipe to fittings, pipe to flanges
shop joints are marked. Shop joints are done to
minimize the erection joints. ( Normally joints after
rolling of pipe or joints connecting to existing flange of
equipment should be avoided at shop ).
MARKING OF ERECTION OR FIELD
JOINT
1.
2.
3.
4.
5.
Erection or field joints are the welding joint done
during erection. The following points to be followed for
deciding erection joint
The spool length shall be such a way decided that there is
no damage to other pipes while erecting ( Normally upto 6
mtr. ).
The spool length shall be decided so that it is easily
transportable.
To avoid distortion in spools more shop joints shall be
avoided ( Straightness after welding shall be checked by
fabricator ).
If there is branch connection and there are chances of
damage to it, then branch connection shall be erection
joint.
One field joint in x, y and z direction shall be kept so that
length adjustment can be made.
MARKING OF OFFSHORE JOINTS
•
1.
2.
3.
4.
5.
Joints made at offshore are known as offshore joints.
Piping Hook up connection between deck and bridge
shall be offshore joint.
Piping connection in between new erected equipment
at offshore with existing deck piping.
Some piping work is kept under hold at Onshore
because of equipment installation at Offshore.
Some piping below Cellar Deck may be avoided at
Onshore to avoid problem during deck installation.
If the instrument to be connected is of long delivery
and to be erected at Offshore then the joint shall be
Offshore joint.
th
t
tf
th = Header thickness
tf = Fillet size ( 0.7 x th or 6mm whichever is less)
t = Full penetration weld size = (th)
tw = Minimum total weld size = (t + tf)
THANK YOU