How many oil rigs have a similar design flaw to the one that failed in the gulf?

Question by retrovertigo: How many oil rigs have a similar design flaw to the one that failed in the gulf?

Everybody is saying how BP cut corners on that rig…or wellhead equipment. (you have to pardon me, I am not an expert) Does anybody know how many other ones there are?

Best answer:

Answer by Bad Moon Rising
What design flaw?
I think you are confusing wellhead equipment with the rig specifications!
EDIT:
The design of every wellhead is pretty much unique. It depends on a large number of technical factors relating to pipe sizes which vary from well to well. The rig design had very very little to do with the “accident”. It is a complicated series of technical issues that are to blame, but at the end of the day it is/was bad decisions that were the cause of the blowout. The circumstances that led to the problems, although not unique, are rare. They have to do with the position (vertically) of reservoirs of different reservoir pressure, and an inability to cement in “production casing” if you lose “circulation” of the much heavier cement in behind the production casing. Normally this is not a fatal problem, but reliance on faulty backup systems, some which appear to have been known to be faulty (Blowout Preventers).
The rig and even the equipment itself, had very little to do with the problem.

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