Ormen Lange Mid North includes the detail and follow-on engineering contract for flowlines and umbilicals.
Mid North-project is the tie-back of Template C to the Phase I gas transportation pipelines going to the Nyhamna onshore process facilities. The tie-in to existing facilities will be via the 30" PLET and Template B located 5.5 km South from Template C. The water depth ranges from 850 m at Template B to 925 m at Template C. The flowline system includes 2x12" production lines, a 6 % 7" MEG line and a control umbilical. The seabed is dominated by deposits from the Storegga slide. This means the seabed is very irregular and with very soft clay and stiff clay features spread out in the area.
REINERTSEN's was awarded the detail and follow-on engineering contract for flowlines and umbilicals.
The main topics included:
- Field layout architecture and flowline routing
- Flowline and coating design
- Pipe-soil interaction definition
- Free span, fatigue and expansion design
- Tie-in spool design
- Seabed intervention design (excavation, rock jumping, jet trenching)
- CP design
- HSE engineering including dropped object analyses
- Lead interface
- Offshore supervision and onshore duty service
Major challenges for the project are related to the very rough terrain and varying seabed conditions and the project development schedule. The technical challenges concern routing and field lay-out, pipeline integrity (static and dynamic), expansion design, seabed intervention methods and optimization and tie-in design.
Animation of the project: http://bit.ly/17QeK9x