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I’ve received information on a pipelay vessel estimated to lay 3.5km 42" pipe per day on DP. In the Nordstream project, I believe the vessel lay speed could go up to 4km.
Someone commented that a rate of 4km per day is too fast. Is there a higher likelihood of wet buckle the faster the laying? On the other hand, is there such a thing as minimum km per day?
Lay rate is greatly controlled by 3 parameters:
- Pipe diameter, ie. length of weld/pass,
- Wall thickness, ie, number of weld passes,
- Length of barge, ie. how many weld layers you can make simultaneously vs number of weld stations that you can fit on it, assuming one pass per weld station.
(With a J-Lay, the number of weld stations in the tower).
Obviously a tiny barge with only 1 weld station is going to have a very slow rate of progress as only a small number of passes can be made at the same time.