kikeh gas pipeline installation - ccop · petronas-petrad presented by: ... to give an overview and...
TRANSCRIPT
Deepwater Workshop
Subsea Tie-back
PETRONAS-PETRAD
Presented by:
M Amirushah B Zakaria Project Engineer | PI | PRD | PMU
Deepwater Pipeline Design
Rigid & Flexible
Objective
Deepwater Pipeline Design Considerations
Project Execution Considerations
Conclusion
PRESENTATION OUTLINE
To give an overview and comparison between
deepwater rigid and flexible pipeline with regard to
design challenges and project execution aspect
OBJECTIVE
Main challenges for pipeline development in deepwater :
• Material selection
• Thermal insulation
• Free span
• Installation
• Repair
Flexi
ble Rigid
Gumusut - Kakap Development Project
Kikeh Development Project
DEEPWATER PIPELINE DESIGN CONSIDERATIONS
Description Rigid Flexible (unbonded)
Material A homogenous steel pipe –
carbon steel, CRA, clad etc
Consists of plastic and steel layers
which are hold by end fitting
Wall Thickness / x
Weight in Air / Water / x
Collapse Resistant / x
Minimum Bending Radius x /
Properties Comparison
Material Selection
Flexible Flowline – Courtesy of Technip Carbon steel pipe End Fitting
Legend:
/ - advantage
X - disadvantage
Description Rigid Flexible
Passive insulation Wet coated - PU, PP foam or
glass reinforced plastic, PiP
Plastic sheathes – additional foam
insulation layer can be added
Active insulation
Hot water circulation and
electrical heated PiP
Additional active heating can be added
For both, combination of insulation coating and pipeline burial can be more cost effective than the thick
insulation coating
Thermal Insulation
Courtesy of Technip
Syntactic PU Pipe-in-Pipe Flexible flowline
Description Rigid Flexible
Free Span Rectification / /
If the as laid free span length exceeds the maximum allowable free span length and confirmed with as
laid span analysis, the free span should be corrected using one of the mitigation methods:
- alteration of seabed
- mid-span supports such as mechanical legs or sand-cement bags / mattresses
Free Span
Several factors influenced the variation from the anticipated span length:
- Spanning predictions not calibrated with the actual field conditions
- Increase in laying tension to protect buckling probably increased the span length
- Accuracy of pipelaying in the pipeline corridor
Pipeline traverse on seabed
Installation
Rigid Flexible
J / S lay DP vessel
Reel lay
Reel lay
Deepwater Pipelay Vessel
Seabed
Installation Configuration
S lay Reel lay J lay
- The installable water depth by the installation vessel varies with pipe size and
weight. It can go to maximum water depth for small pipe sizes
Installation
TDP
Welding
station 1
NDT
station
Welding
station 4
Welding
station 3
Welding
station 2
Repair
station Tensioner 1 Tensioner 2 Tensioner 3
Surface
cleaning HSS
station
HDPUF
station
Station 1- 4) Welding
(GMAW using Serimax
dual torch machine)
Station 5) NDT API 1104 3 x 80 mT Tensioner Station 6) Repair (SMAW/GSFCAW)
Station 8) HSS coating
Station 7) Surface cleaning
Station 9) HDPUF injection Stinger
S lay
Installation
Installation
J lay
Workstation
Erector
J tower
Reel Drive System Vertical Lay System
Reel lay
Midline Connection
Installation
Description Rigid Flexible
Diverless Pipeline Repair
System (DPRS)
/ x
- Availability of DPRS would minimize the downtime due to pipeline damage
Repair
Pipeline damage possibly can happen due to:
- Local defect – weld defect, pin hole, internal corrosion
- Nature - landslide / seismic event, hurricane
- Anchor drag
- Installation
- Material fatigue
Permanent Repair Clamp
Vertical DPRS
Legend:
/ - advantage
X - disadvantage
Cost Comparison
Item Rigid Flexible
*Procurement Cost (USD/m) 750 – 850 2500 - 6000
**Installation vessel charter
rate (USD’000/day) - With high tension lay system (for
laying and recovering)
600 - 750
(S / J lay vessel)
~500
(Reel lay vessel)
Other materials More subsea
structure and
connection e.g.
PLET, jumper
Less subsea structure
and subsea connection
Note: *Estimated based on12” ID pipeline (with 1” GSPU insulation for rigid pipe)
**For high tension lay system, ~400t tensioner
PROJECT EXECUTION CONSIDERATIONS
Schedule Comparison
Item Rigid Flexible
Average Pipelay
Rate
*42 – 104 m/hr
(J / S lay)
**200 – 500 m/hr
Pipeline Storage
capacity
~ 4000t (min) Multiple reels Pipe length varies based on pipe size,
carousel capacity & deck size
Other activities Installation of subsea
structure, cleaning,
gauging etc
Less activities
Note: *Depends on pipe size and wall thickness
**Pipe alignment - midline connection can take hours
Understanding of the ways to manage challenges in deepwater pipeline
development will ensure safe design, safe operation and give benefit to
the overall project capital and expenditure.
CONCLUSION
THANK YOU