Speed of pipelay per day

SOURCE
https://www.eng-tips.com/viewthread.cfm?qid=331234
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QUESTION
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?

REPLIES

BigInch
Lay rate is greatly controlled by 3 parameters:

  1. Pipe diameter, ie. length of weld/pass,
  2. Wall thickness, ie, number of weld passes,
  3. 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.