Oil & Gas introduction Course for Non-Engineers SEC

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Module 4

Pipe laying

Oil & Gas introduction Course for Non-Engineers SEC

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1. Pre-lay Survey

Inspecting the seabed along the intended pipe line route before construction

Consisting of:

- Desktop study- Bathymetry profile (side scan)- Geotechnical sampling- Visual inspection

Oil & Gas introduction Course for Non-Engineers SEC

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2. Sand Waves (or Dunes)

San Francisco Bay Dubai Coast

Ridges on the seabed formed by current

Oil & Gas introduction Course for Non-Engineers SEC

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3. Span Correction

Measure to prevent free span of pipe line

Free Span

Oil & Gas introduction Course for Non-Engineers SEC

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4. Landfall

Land fall Ca Mau

Location where pipe line comes onshore

Trenching

Oil & Gas introduction Course for Non-Engineers SEC

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5. J-Lay

Application: Water depth more than 200m

Pipes have J-shape when in laying process

J-lay Tower

Lay direction

Oil & Gas introduction Course for Non-Engineers SEC

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6. S-Lay

Application: Shallow water (Vietnam)

Pipes have S-shape when in laying process

Monitoring

Lay direction

Oil & Gas introduction Course for Non-Engineers SEC

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7. Stinger

Support frame to guide pipe line overboard during S-laying

To prevent small bending radius

Oil & Gas introduction Course for Non-Engineers SEC

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8. Pipe Laying Ship (or Vessel)

Application: Small diameter pipe with small bending radius

Mono hull vessels to lay pipe lines offshore

Oil & Gas introduction Course for Non-Engineers SEC

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9. Pipe Laying Barge

Flat barge or Semi used to lay offshore pipe lines

Application: Larger diameter pipe

Drivers for choice?;

- Water depth- Diameter pipe line

Oil & Gas introduction Course for Non-Engineers SEC

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10. Pipe Tensioner

Gripper on the vessel that holds the string during the laying process

Oil & Gas introduction Course for Non-Engineers SEC

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11. Beveling

Machining a sloped surface on the pipe end for welding purposes

Oil & Gas introduction Course for Non-Engineers SEC

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12. Line up Tools

Tool to align two joints of pipe before welding

IPEC Canada

Oil & Gas introduction Course for Non-Engineers SEC

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13. Field Weld

Welding two joints of pipe together offshore

Oil & Gas introduction Course for Non-Engineers SEC

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14. Field Joint

Completed connection between two joints done offshore

Oil & Gas introduction Course for Non-Engineers SEC

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15. Welded Pipe

Steel pipe made of plate steel

Longitudinal pipeSpiral welded Pipe

Use: Construction purposes/small Wall thickness

Use: Big diameter/Wall thickness Pipe lines

Oil & Gas introduction Course for Non-Engineers SEC

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16. Seamless pipe

Hot rolled steel pipe with no weld

Use: Petrochemical industry, small diameters/big wall thickness

Drivers for choice?;

- Wall thickness- Diameter pipe- Mechanical properties

Oil & Gas introduction Course for Non-Engineers SEC

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17. Weight coat

Concrete jacket around the pipe line to weigh it down and protect it

Use: Offshore Pipelines Length of one Joint: 12 m

Oil & Gas introduction Course for Non-Engineers SEC

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18. PLEM

Pipe Line End Manifold = Protecting structure housing valves and T-pieces

Purpose: Fix position of pipe line end and protect

valves/actuators from fishing nets and anchors

Oil & Gas introduction Course for Non-Engineers SEC

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19. Spool Piece

Small pipe piece made to order to connect two flanged pipe ends

Measurement by Divers: Geometrics

Can also be used as expansion piece

Oil & Gas introduction Course for Non-Engineers SEC

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20. Pressure testing

Testing the pipeline for leaks by pressurizing it and monitoring the pressure

Test pressure depends on design pressure and safety factor

Important moment for pipe laying contractor

Oil & Gas introduction Course for Non-Engineers SEC

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21. Testable Gasket

Sealing between two flanges that can be tested without pressurizing the line

Connection test kit

Flange connection

Oil & Gas introduction Course for Non-Engineers SEC

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22. Pigs

Plugs that are send trough the pipe line by compressed air or water to perform duties

Pig Launch

Duties:

CleaningMeasuringInspection

ROSENMalaysia

Oil & Gas introduction Course for Non-Engineers SEC

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23. Cleaning (Pre commissioning)

Remove all debris and particles from the pipe line

Oil & Gas introduction Course for Non-Engineers SEC

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24. Drying (Pre commissioning)

Remove all water residue and vapor before commissioning of the pipe line

Purpose:To avoid corrosion (Hydrate) and

contamination of product

Techniques used:

1. Glycol/Methanol2. Air drying3. Vacuum drying

Pig train