Are you saying that all the human beings out there that know how to do such things would go work at mcdonalds if halliburton failed?
No, they work work for Schlumberger or BJs. They both do Offshore cementing, as well as land work. In fact most of the rigs I have worked on, have Schlumberger Cementers. On the rig i currently work, one of the Schlumberger Cementers started out in the oil field working for Halliburton up in Oklahoma.
http://latimesblogs.latimes.com/gree...onnection.html
According to experts cited in Friday's Wall St. Journal, the timing of last week's cement job in relation to the explosion -- only 20 hours beforehand, and the history of cement problems in other blowouts "point to it as a possible culprit." Robert MacKenzie, managing director of energy and natural resources at FBR Capital Markets and a former cementing engineer, told the Journal, "The initial likely cause of gas coming to the surface had something to do with the cement."
The cementing operation might have been an contributing factor of gas being being in the hole but also its what happened before the casing the job that is equally important.
Normal SOP is to finish drilling 100+ feet past the lowest zone they want to produce and in usually in a non-porous rock such as shale. Next, they circulate the hole clean of cuttings & gas and ensure that the well is static. Short trip to the casing shoe, trip to bottom and then circulate the hole clean some more. Then trip out of the hole.
Rig up casing equipment and run in the hole with casing. While setting casing on bottom, normal SOP is to circulate bottoms up and ensure that there is very little to no gas in the whole. If there is still a high amount of gas the mudweight can be increased to keep the gas low. This can happen before they trip out of the hole or while circualting on bottom with casing. Then Cement, Disconnect the landing Drill pipe from the casing and circulate bottoms up to get any gas out, and again ensure the well is static.
It will be interesting to found out what was done to prepare the hole prior to the cement operation.
http://rigzone.com/news/article.asp?a_id=92021
Halliburton had completed the cementing of the final production casing string in accordance with the well design approximately 20 hours prior to the incident. The cement slurry design was consistent with that utilized in other similar applications. In accordance with accepted industry practice approved by our customers, tests demonstrating the integrity of the production casing string were completed.
I wonder if that means they did a casing pressure test, or something to ensure that the cement and casing was holding. I hope that also mean the casing hanger was properly set and sealed. If gas came up the back side of the casing and the casing hanging was not properly set and sealed, then that not on Halliburton cementers. That is the rig and ultimately the company that BP hired to provide the casing hanger.
There are a lot of causes and factors that still need to be investigated. The cement job is just one of the many pieces to the puzzle that need to be explored. But lets not be judge and executioner until the investigation is over
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