In casingproductionstraighteningdetermines the shapeprecisionandresidualstress in casing, which have stronginfluenceon the collapse resistance of casing.
"We have known for some time that the cement used to secure the productioncasing and isolate the hydrocarbon zone at the bottom of the Macondo well must have failed in some manner, " the letter said, noting that BP used a "nitrogen foam cement" recommended and supplied by Halliburton.
Although the unit we saw today has functional guts, we're told that the casing is pre-production -- not to say that "production" BUGbases need to look amazing, anyway, considering that they're frequently used for prototyping themselves.
Then there is Halliburton, which was contracted to cement the production liner in the well casing, effectively sealing off the reservoir from the well bore.