Pipeline Design and Construction

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Pipeline Design and Construction

Presented by: Presented by: Engr

Engr. Md. . Md. SanwarSanwar HossainHossain Dy

Dy. Manager , Operation. Manager , Operation Gas Transmission Co. Ltd. Gas Transmission Co. Ltd.

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Pipeline design

QQ_mmscfd_mmscfd=0.00128084((P=0.00128084((P₁₁22--PP₂₂22)/L)/L_miles_miles))0.510.51DD2.532.53

For successful implementation of a pipeline project, For successful implementation of a pipeline project,

the following steps are to be considered in general: the following steps are to be considered in general:

1. Market survey

1. Market survey-- Present & future demandPresent & future demand 2. MAOP & Design pressure

2. MAOP & Design pressure

3. Map of the preliminary selected pipeline route (L) 3. Map of the preliminary selected pipeline route (L)

4. Pipe Size (D) 4. Pipe Size (D)

5. Wall thickness (t) 5. Wall thickness (t)

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Pipeline design ( contd.)

6. Pipe specification / grade 6. Pipe specification / grade

7. Bill of materials 7. Bill of materials

8. Total cost estimate 8. Total cost estimate 9. Selection of ROW 9. Selection of ROW

10. Detailed survey and Preparation of alignment 10. Detailed survey and Preparation of alignment

drawings drawings

(4)

Pipeline design ( contd.)

Load consideration: Load consideration:

In earlier days , pipeline design was done In earlier days , pipeline design was done

considering the present load and 15 to 30% considering the present load and 15 to 30%

increment of load. increment of load.

NowNow--a days, the use of natural gas increased a days, the use of natural gas increased

tremendously. As a result the concept of pipeline tremendously. As a result the concept of pipeline

design has also changed. design has also changed.

Presently pipeline design is being done considering Presently pipeline design is being done considering

the present load as well as the assumed gas load of the present load as well as the assumed gas load of

the that particular area for the next 20 years ( the that particular area for the next 20 years (

effective life of the pipeline) effective life of the pipeline)

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Pipeline design (Contd.)

Modified Panhandle equationModified Panhandle equation-- most useful for most useful for

transmission pipeline : transmission pipeline :

QQ_mmscfd_mmscfd=0.00128084((P=0.00128084((P₁₁22--PP₂₂22)/L)/L_miles_miles))0.510.51DD2.532.53

where , P

where , P₁₁=Upstream pressure, PSIA=Upstream pressure, PSIA P

P₂₂=Downstream pressure, PSIA=Downstream pressure, PSIA D=Inside pipe

(6)

Pipeline design (contd.)

t= DP/(2YFL JT)t= DP/(2YFL JT)

where, where,

t=Pipe wall thickness, mm t=Pipe wall thickness, mm

P=design pressure ,psig P=design pressure ,psig

D=outside

D=outside diadia of pipe in mmof pipe in mm

Y=minimum yield strength, psig Y=minimum yield strength, psig

F=design factor F=design factor

L= Location factor based on class location L= Location factor based on class location

J=welding joint factor J=welding joint factor

T=Temp.

(7)

Line

Pipe

: API 5L Grades

Grade

Grade Minimum yield Minimum yield strength(

strength( MPa)MPa) Minimum Tensile strength( MPaMinimum Tensile strength( MPa)) B B 241241 413413 X42 X42 289289 413413 X46 X46 317317 434434 X52 X52 358358 455455 X56 X56 386386 489489 X60 X60 413413 517517 X65 X65 448448 530530 X70 X70 482482 565565 X80 X80 551551 620620

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Design

and Location Factor

_{and Location Factor}

Canadian Standards association (CSA)

suggests design factor of 0.8 While location

factors are:

Area

Area Class Class Location

Location ASMEASME CSACSA Deserted Deserted 11 0.720.72 0.800.80 Village Village 22 0.600.60 0.720.72 City City 33 0.500.50 0.560.56 Metropolis Metropolis 44 0.400.40 0.440.44

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Joint factor :

Weld type

Weld type ASME B31.8ASME B31.8 Seamless Seamless 11 ERW ERW 11 SAW SAW 11 But Welled But Welled 0.60.6 Spiral seam Spiral seam 0.80.8

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Temperature factor:

Temperature (

Temperature ( ̊ F)̊ F) ASMEASME-- B31.8B31.8 Up to 250 Up to 250 1.001.00 251 251--300300 0.970.97 301 301--400400 0.930.93 401 401--450450 0.910.91 451 and above 451 and above 0.870.87

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Pipeline Construction Process

DPP DPP

Land acquisition & RequisitionLand acquisition & Requisition

Tender Document PreparationTender Document Preparation

TenderTender

Bid EvaluationBid Evaluation

Tender AwardTender Award

ProcurementProcurement

MobilizationMobilization

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Pipeline Construction Process (contd.)

Welding and NDTWelding and NDT

Trenching, Lowering & BackfillingTrenching, Lowering & Backfilling

TieTie--inin

Hydrostatic TestingHydrostatic Testing CleaningCleaning CommissioningCommissioning OperationOperation

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Pre construction

ROW Acquisition & RequisitionROW Acquisition & Requisition

--ROW SelectionROW Selection

--DC OfficeDC Office

--CompensationCompensation

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Pre construction (Contd.)

General Guideline for Pipeline Routing

Minimize overall pipe length.Minimize overall pipe length.

Parallel existing utility corridors (Highway, High Parallel existing utility corridors (Highway, High

tension Electric transmission line). tension Electric transmission line).

Avoid areas of high population density.Avoid areas of high population density.

Minimize highways, railways, river, Minimize highways, railways, river, khalskhals, canals, , canals,

ponds, hills & mountains crossing to reduce the ponds, hills & mountains crossing to reduce the

project cost. project cost.

Cross highways, railways, river, Cross highways, railways, river, khalskhals, canals at or , canals at or

close to 90 deg. angle. close to 90 deg. angle.

Minimize crossover of existing facilities.Minimize crossover of existing facilities.

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Pre construction (Contd.)

General Guideline for Pipeline Routing

Avoid the following areas:Avoid the following areas: •

• Swamps and WetlandsSwamps and Wetlands

•

• Rocky areasRocky areas

•

• Unstable soilUnstable soil

•

• Populated areasPopulated areas

•

• Historical areasHistorical areas

•

• Environmentally sensitive areas ( Forest, Tea Environmentally sensitive areas ( Forest, Tea

garden , Rubber garden etc.) garden , Rubber garden etc.)

•

• Religious sensitive areas ( Mosque , Graveyard, Religious sensitive areas ( Mosque , Graveyard,

temple etc.) temple etc.)

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Pre construction (Contd.)

Land acquisition / Requisition:

Normally Normally 10 m10 m wide strip along the proposed wide strip along the proposed

pipeline route is to be acquisition and a

pipeline route is to be acquisition and a 15 m15 m wide wide strip on one side of the acquisition strip is to be

strip on one side of the acquisition strip is to be requisition.

requisition.

Acquisition is permanent possession for use of land Acquisition is permanent possession for use of land

but requisition is completely a temporary affair , only but requisition is completely a temporary affair , only

for the working period. for the working period.

For scraper station and Valve station separate block For scraper station and Valve station separate block

lands of required size have to be acquisition. lands of required size have to be acquisition.

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Pre construction (Contd.)

Submission of proposal for land acquisition & requisition:

The company submit the proposal with requisite no. of The company submit the proposal with requisite no. of

drawings (Normally

drawings (Normally mouzamouza map) showing acquisition & map) showing acquisition & requisition strip in two distinct colors (red for requisition strip in two distinct colors (red for

acquisition & green for requisition) to DC office. acquisition & green for requisition) to DC office.

The process of acquisition & requisition in our country The process of acquisition & requisition in our country

is done through the DC office of the particular district. is done through the DC office of the particular district.

The whole process continues in accordance with The whole process continues in accordance with

Ordinance, Acts, Rules & Regulations issued by the Ordinance, Acts, Rules & Regulations issued by the

government from time to time. government from time to time.

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Pre construction (contd.)

TenderTender

--FloatingFloating

--Bid Receiving & EvaluationBid Receiving & Evaluation

--Contract Award & Contract ManagementContract Award & Contract Management

ProcurementProcurement

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Major steps for pipeline Construction

Cleaning & Grading the ROWCleaning & Grading the ROW

Stringing the pipe along ROWStringing the pipe along ROW

Welding the pipe joints togetherWelding the pipe joints together

NDT of welding jointsNDT of welding joints

Coating & Wrapping Coating & Wrapping

Ditching / Trenching Ditching / Trenching

Holiday testHoliday test

Lowering & backfillingLowering & backfilling

PiggingPigging

Hydro TestHydro Test

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Equipment used for Pipeline Construction:

BulldozerBulldozer-- Used to clearing & grading of ROW.Used to clearing & grading of ROW.

ExcavatorExcavator--Used to trenching , pipe lifting, pulling the Used to trenching , pipe lifting, pulling the

welding machine etc. welding machine etc.

Side boomSide boom-- Used to lift the pipe during welding and Used to lift the pipe during welding and

lay the pipeline in the trench. lay the pipeline in the trench.

Crane Crane –– Used to handle heavy equipments and Used to handle heavy equipments and

machineries. machineries.

Welding generatorWelding generator

Trailer/ TruckTrailer/ Truck-- used to carry the line pipe from store used to carry the line pipe from store

yard to the working site. yard to the working site.

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Pipeline construction Equipment

Excavator Excavator

Side boom Side boom

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ROW Clearing & Grading

ROW is cleared of barriers and graded for ROW is cleared of barriers and graded for

movement of construction equipment, materials movement of construction equipment, materials

and ultimately construction of pipeline. and ultimately construction of pipeline.

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Pre Welding Activities

Welders testWelders test -- an exam for the welders before an exam for the welders before

going to production weld. going to production weld.

Selection CriterionSelection Criterion-- Visual inspection & NDT ( Visual inspection & NDT ( API API

1104) 1104)

PQR / WPS TestPQR / WPS Test

--Tensile strength testTensile strength test

--Face bend testFace bend test

--Root bend testRoot bend test

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Stringing

Stringing is aligning the Stringing is aligning the pipe along the ROW

pipe along the ROW

ready for welding .

Trailer, Side boom etc Trailer, Side boom etc are used to stringing the

are used to stringing the

pipe.

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Welding

Root pass/ Stringer passRoot pass/ Stringer pass

Hot passHot pass

Filling pass Filling pass

Cap PassCap Pass

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NDT ( Non Destructive Test)

Dye Dye penetrantpenetrant testtest

Magnetic Particle testMagnetic Particle test

Eddy current testEddy current test

Radiographic testRadiographic test

Ultrasonic testUltrasonic test

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NDT ( Non Destructive Test)

Radiography TestRadiography Test

o o EquipmentEquipment o o MethodMethod o o SourceSource o

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NDT ( Non Destructive Test)

Ultrasonic TestUltrasonic Test

o o EquipmentEquipment o o MethodMethod o o SourceSource o

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Common welding defects

Porosity

Cluster porosity

Slag inclusion

Lack of fusion

Lack of penetration

Internal concavity

Burn through

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Welding defects:

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Welding defects:

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Tie

-

in welds

The final weld to join two separate section

together.

Should be properly aligned without use of

jacks or any external force.

Should be done within operating temp ( 5

-

30

30 deg. Celsius).

deg. Celsius).

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Roads and Railway Crossing

Two different ways Two different ways

Thrust boring/ Horizontal boring methodThrust boring/ Horizontal boring method

--Drill a hole under the roadway without disturbing Drill a hole under the roadway without disturbing the road/ rail surface.

the road/ rail surface.

A casing pipe is placed through the hole and then A casing pipe is placed through the hole and then

the pipeline is placed inside the casing. the pipeline is placed inside the casing.

Spacer is used to center the pipeline within the Spacer is used to center the pipeline within the

casing pipe. casing pipe.

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Pipe Coating

All except a portion ( about 6 inch ) of each pipe is All except a portion ( about 6 inch ) of each pipe is

often coated in the factory before deliver to the site. often coated in the factory before deliver to the site.

Three types of coatingThree types of coating

--3LPE coating3LPE coating

--FBE coatingFBE coating

--Polyethylene coatingPolyethylene coating

3LPE coating 3LPE coating

--Apply adhesive on clean pipe surfaceApply adhesive on clean pipe surface

--Epoxy paint ( 40Epoxy paint ( 40--100 micron)100 micron)

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Bare pipe

Steel Pipe without coating Steel Pipe without coating

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3 LPE Coated Pipe

Features:Features:

--Cleaning ( sand Cleaning ( sand Blasting)

Blasting)

--Apply AdhesiveApply Adhesive

--Apply epoxy paint ( 40Apply epoxy paint ( 40- -100 micron thick)

100 micron thick)

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Concrete Coated Pipe

Features:Features:

--Apply 3LPE CoatingApply 3LPE Coating

--Set wire mesh above 3LPE Set wire mesh above 3LPE Coating

Coating

--Apply Concrete coatingApply Concrete coating

-- Provide Provide ––VeVe buoyancy buoyancy

force force

-- Apply on ditch, canal , Apply on ditch, canal ,

pond,

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Set

-

_-

on

_on

-

_-

Weight

_Weight

Features:Features:

--Put on above 3LPE coated Put on above 3LPE coated pipe

pipe

--one on each pipeone on each pipe

--Provide Provide ––VeVe buoyancy buoyancy force

force

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Joint coating

Heat shrink sleevesHeat shrink sleeves

--Approx. 14 inch length and Approx. 14 inch length and diadia larger than pipe larger than pipe diadia..

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Ditching, Holyday test, Lowering & Backfilling

DitchingDitching

Holyday testHolyday test

-- Apply 10 KV on coated pipe surfaceApply 10 KV on coated pipe surface

--Any coating defect will result an audible sound.Any coating defect will result an audible sound.

LoweringLowering

-- Lay pipeline on Trench of approx. 1.2 m depthLay pipeline on Trench of approx. 1.2 m depth

--Put Put

Set

-

on

-

weight

on burriedon burried pipe for antipipe for anti--buoyancy buoyancy force

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Testing :

Brush / cup pigBrush / cup pig

--Clean internal rustClean internal rust

Gauge pigGauge pig

--To check pipe To check pipe ovalityovality

Foam PigFoam Pig

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Pig Receiver

To receive pig at the To receive pig at the

terminal point terminal point

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Pig Traps

Pig Receiver connected with pipeline Pig Receiver connected with pipeline

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Hydro test

After mechanical completion of pipeline After mechanical completion of pipeline

Min test pressure should be 1.5 times of design Min test pressure should be 1.5 times of design

pressure. pressure.

Conventional hydro test pressure for high pressure Conventional hydro test pressure for high pressure

pipeline= 1.5 X 1135

pipeline= 1.5 X 1135 psipsi = 1703 = 1703 psipsi

Before commencing pressurization need to obtain Before commencing pressurization need to obtain

necessary permission from the competent authority necessary permission from the competent authority .As per Gas Safety rules Department of explosive is .As per Gas Safety rules Department of explosive is

the competent authority in Bangladesh. the competent authority in Bangladesh.

Prior notification of testing should be given, in Prior notification of testing should be given, in

writing to persons in the vicinity of the pipeline . writing to persons in the vicinity of the pipeline .

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Hydro test (contd.)

Prior notification of testing should be given to local Prior notification of testing should be given to local

police and other authorities, who may be affected. police and other authorities, who may be affected.

Warning notice stating “WarningWarning notice stating “Warning--PipeLinePipeLine Under Under

Test” and “No Parking” should be placed at Test” and “No Parking” should be placed at

appropriate locations for the duration of the test. appropriate locations for the duration of the test.

Patrols should be provided to watch special points of Patrols should be provided to watch special points of

hazard during the test, in particular road, rail and hazard during the test, in particular road, rail and

water crossing and points of public access. water crossing and points of public access.

Standby emergency crew should be available to deal Standby emergency crew should be available to deal

any unwanted situation. any unwanted situation.

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Commissioning

Prior to the commissioning the pipeline should be dry Prior to the commissioning the pipeline should be dry

up. up.

Methods available for drying up are:Methods available for drying up are:

--Using dry air (compressor) push a series of foam Using dry air (compressor) push a series of foam pigs through the pipeline collecting water until the pigs through the pipeline collecting water until the

required dryness is achieved. required dryness is achieved.

The pipeline should be purged of before the The pipeline should be purged of before the

admission of the gas to be transmitted . admission of the gas to be transmitted .

Use inert gas to purge of air.Use inert gas to purge of air.

After drying up a pipeline can be commissioned After drying up a pipeline can be commissioned

straight to gas. straight to gas.

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Codes and Standards

ASME B31.8 ( Onshore & Offshore)ASME B31.8 ( Onshore & Offshore)

ASME B16.5 (Flange & Flange Fittings)ASME B16.5 (Flange & Flange Fittings)

ASME B16.21 ( Gaskets for Flanges)ASME B16.21 ( Gaskets for Flanges)

API 5L ( Line Pipe)API 5L ( Line Pipe)

API 6D (Valves)API 6D (Valves)

API 1104 (Welding Inspection)API 1104 (Welding Inspection)

ASME UASME U-- Stamp ( Pig Traps & Launcher)Stamp ( Pig Traps & Launcher)

ASME Boiler & Pressure Vessel Code ( Scrubber, KOD ASME Boiler & Pressure Vessel Code ( Scrubber, KOD

and Other pressure Vessels) and Other pressure Vessels)