Pipeline Design and ConstructionPipeline Design and Construction

Presented by:Presented by:EngrEngr. Md. . Md. SanwarSanwar HossainHossainDyDy. Manager , Operation. Manager , OperationGas Transmission Co. Ltd.Gas Transmission Co. Ltd.

Pipeline designPipeline design

QQmmscfdmmscfd=0.00128084((P=0.00128084((P1122--PP22

22)/L)/Lmilesmiles))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 survey1. Market survey-- Present & future demandPresent & future demand2. 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)

Pipeline design ( contd.)Pipeline design ( contd.)

6. Pipe specification / grade6. Pipe specification / grade7. Bill of materials7. Bill of materials8. Total cost estimate8. Total cost estimate9. Selection of ROW 9. Selection of ROW 10. Detailed survey and Preparation of alignment 10. Detailed survey and Preparation of alignment drawingsdrawings

Pipeline design ( contd.)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)

Pipeline design (Contd.)Pipeline design (Contd.)

Modified Panhandle equationModified Panhandle equation-- most useful for most useful for transmission pipeline :transmission pipeline :QQmmscfdmmscfd=0.00128084((P=0.00128084((P11

22--PP2222)/L)/Lmilesmiles))0.510.51DD2.532.53

where , Pwhere , P11=Upstream pressure, PSIA=Upstream pressure, PSIAPP22=Downstream pressure, PSIA=Downstream pressure, PSIAD=Inside pipe D=Inside pipe diadia , inch, inch

Pipeline design (contd.)Pipeline design (contd.)

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

t=Pipe wall thickness, mmt=Pipe wall thickness, mmP=design pressure ,psigP=design pressure ,psigD=outside D=outside diadia of pipe in mmof pipe in mmY=minimum yield strength, psigY=minimum yield strength, psigF=design factorF=design factorL= Location factor based on class locationL= Location factor based on class locationJ=welding joint factorJ=welding joint factorT=Temp. T=Temp. deratingderating factorfactor

Line Line PipePipe: API 5L Grades: API 5L Grades

GradeGrade Minimum yield Minimum yield strength( strength( MPaMPa))

Minimum Tensile Minimum Tensile strength( strength( MPaMPa))

BB 241241 413413

X42X42 289289 413413X46X46 317317 434434X52X52 358358 455455

X56X56 386386 489489X60X60 413413 517517X65X65 448448 530530X70X70 482482 565565X80X80 551551 620620

DesignDesign and Location Factorand Location FactorCanadian Standards association (CSA) Canadian Standards association (CSA) suggests design factor of 0.8 While location suggests design factor of 0.8 While location factors are:factors are:

AreaArea Class Class LocationLocation

ASMEASME CSACSA

DesertedDeserted 11 0.720.72 0.800.80

VillageVillage 22 0.600.60 0.720.72

CityCity 33 0.500.50 0.560.56MetropolisMetropolis 44 0.400.40 0.440.44

Joint factor :Joint factor :

Weld typeWeld type ASME B31.8ASME B31.8

SeamlessSeamless 11

ERWERW 11

SAWSAW 11

But WelledBut Welled 0.60.6

Spiral seamSpiral seam 0.80.8

Temperature factor:Temperature factor:

Temperature ( Temperature ( ̊ F)̊ F) ASMEASME-- B31.8B31.8

Up to 250Up to 250 1.001.00

251251--300300 0.970.97

301301--400400 0.930.93

401401--450450 0.910.91

451 and above451 and above 0.870.87

Pipeline Construction ProcessPipeline Construction Process

DPP DPP Land acquisition & RequisitionLand acquisition & RequisitionTender Document PreparationTender Document PreparationTenderTenderBid EvaluationBid EvaluationTender AwardTender AwardProcurementProcurementMobilizationMobilizationClearing, Grading and StringingClearing, Grading and Stringing

Pipeline Construction Process (contd.)Pipeline Construction Process (contd.)

Welding and NDTWelding and NDTTrenching, Lowering & BackfillingTrenching, Lowering & BackfillingTieTie--ininHydrostatic TestingHydrostatic TestingCleaningCleaningCommissioningCommissioningOperationOperation

Pre constructionPre construction

ROW Acquisition & RequisitionROW Acquisition & Requisition--ROW SelectionROW Selection--DC OfficeDC Office--CompensationCompensation--Crop CompensationCrop Compensation

Pre construction (Contd.)Pre construction (Contd.)General Guideline for Pipeline RoutingGeneral 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.Provide adequate construction area.Provide adequate construction area.

Pre construction (Contd.)Pre construction (Contd.)General Guideline for Pipeline RoutingGeneral Guideline for Pipeline RoutingAvoid 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.)

Pre construction (Contd.)Pre construction (Contd.)

Land acquisition / Requisition: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.

Pre construction (Contd.)Pre construction (Contd.)

Submission of proposal for land acquisition & requisition: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.

Pre construction (contd.)Pre construction (contd.)

TenderTender--FloatingFloating--Bid Receiving & EvaluationBid Receiving & Evaluation--Contract Award & Contract ManagementContract Award & Contract ManagementProcurementProcurementMobilizationMobilization

Major steps for pipeline ConstructionMajor steps for pipeline Construction

Cleaning & Grading the ROWCleaning & Grading the ROWStringing the pipe along ROWStringing the pipe along ROWWelding the pipe joints togetherWelding the pipe joints togetherNDT of welding jointsNDT of welding jointsCoating & Wrapping Coating & Wrapping Ditching / Trenching Ditching / Trenching Holiday testHoliday testLowering & backfillingLowering & backfillingPiggingPiggingHydro TestHydro TestCommissioningCommissioning

Equipment used for Pipeline Construction: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 generatorTrailer/ 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.

Pipeline construction EquipmentPipeline construction Equipment

ExcavatorExcavator

Side boomSide boom

ROW Clearing & GradingROW 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.

Pre Welding ActivitiesPre 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--Charpy V notch testCharpy V notch test

StringingStringingStringing is aligning the Stringing is aligning the pipe along the ROW pipe along the ROW ready for welding .ready for welding .Trailer, Side boom etc Trailer, Side boom etc are used to stringing the are used to stringing the pipe.pipe.

WeldingWelding

Root pass/ Stringer passRoot pass/ Stringer passHot passHot passFilling pass Filling pass Cap PassCap PassCleaning the weldsCleaning the welds

NDT ( Non Destructive Test)NDT ( Non Destructive Test)

Dye Dye penetrantpenetrant testtestMagnetic Particle testMagnetic Particle testEddy current testEddy current testRadiographic testRadiographic testUltrasonic testUltrasonic testNDT personnel certification ( Level 1,2 & 3)NDT personnel certification ( Level 1,2 & 3)

NDT ( Non Destructive Test)NDT ( Non Destructive Test)

Radiography TestRadiography Testoo EquipmentEquipmentoo MethodMethodoo SourceSourceoo Film examination as Per API 1104 StandardFilm examination as Per API 1104 Standard

NDT ( Non Destructive Test)NDT ( Non Destructive Test)

Ultrasonic TestUltrasonic Testoo EquipmentEquipmentoo MethodMethodoo SourceSourceoo Weld examinationWeld examination

Common welding defectsCommon welding defects

PorosityPorosityCluster porosityCluster porositySlag inclusionSlag inclusionLack of fusionLack of fusionLack of penetrationLack of penetrationInternal concavityInternal concavityBurn throughBurn throughCrackCrack

Welding defects:Welding defects:

Welding defects:Welding defects:

TieTie--in weldsin welds

The final weld to join two separate section The final weld to join two separate section together.together.Should be properly aligned without use of Should be properly aligned without use of jacks or any external force.jacks or any external force.Should be done within operating temp ( 5Should be done within operating temp ( 5--30 30 deg. Celsius).deg. Celsius).NDT test.NDT test.

Roads and Railway CrossingRoads 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.

Open Cut methodOpen Cut method

Pipe CoatingPipe CoatingAll 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)--Polyethylene coatingPolyethylene coating

Bare pipeBare pipe

Steel Pipe without coatingSteel Pipe without coating

3 LPE Coated Pipe3 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)--Polyethylene coatingPolyethylene coating

Concrete Coated PipeConcrete Coated Pipe

Features:Features:--Apply 3LPE CoatingApply 3LPE Coating--Set wire mesh above 3LPE Set wire mesh above 3LPE

CoatingCoating--Apply Concrete coatingApply Concrete coating-- Provide Provide ––VeVe buoyancy buoyancy

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

pond, pond, khalkhal, small river , small river

SetSet--onon--WeightWeight

Features:Features:--Put on above 3LPE coated Put on above 3LPE coated

pipepipe--one on each pipeone on each pipe--Provide Provide ––VeVe buoyancy buoyancy

forceforce-- Apply on marshy areaApply on marshy area

Joint coatingJoint coating

Heat shrink sleevesHeat shrink sleeves--Approx. 14 inch length and Approx. 14 inch length and diadia larger than pipe larger than pipe diadia..--Shrink on applying heat and fitted to the pipe.Shrink on applying heat and fitted to the pipe.

Ditching, Holyday test, Lowering & BackfillingDitching, Holyday test, Lowering & Backfilling

DitchingDitchingHolyday 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 SetSet--onon--weightweight on on burriedburried pipe for antipipe for anti--buoyancy buoyancy forceforce

Testing :Testing :

Brush / cup pigBrush / cup pig--Clean internal rustClean internal rustGauge pigGauge pig--To check pipe To check pipe ovalityovalityFoam PigFoam Pig--To dry internal surfaceTo dry internal surface

Pig ReceiverPig Receiver

To receive pig at the To receive pig at the terminal pointterminal point

Pig TrapsPig Traps

Pig Receiver connected with pipelinePig Receiver connected with pipeline

Hydro testHydro 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 psipsiBefore 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 .

Hydro test (contd.)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.

CommissioningCommissioning

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.

Codes and StandardsCodes 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)