>Wait .. drill pipe, or casing? Everything I read as well as what I heard from a well placed source says casing. The WSJ is discussing a bad cement job as the cause, as are a number of other papers. What I've heard from my source is 100% consistent with the well having been cased and cemented. Indeed, the source was talking about it happening during the changeover in mud fluids to salt water. I presume the pressure was kept in check by heavy mud before, but once it is cased and cemented, the casing and the cement should hold back the pressure differential between 16k psi of salt water (IIRC, it' was below 30k feet), and the gas. I haven't read the last casing size, but making reasonable guesses from what I read, we're talking about at least 3/4" thick pipe. I'm guessing an ID of 3.5". If they were "really" good at drilling, maybe 6" ID and 7 3/4" OD.....but that's about as big as I could imagine with that kind of depth.
>Looked like they were in the process >of casing the well to get it ready for production, which would mean >casing. I'm pretty sure it was after that, and this is _really_ critical. If my understanding is correct, they were switching the wellbore fluid to salt water in preparation for completing the well by shooting holes in the casing and the cement (perforating), to allow the oil to flow. Since they measured pressures on the way down, they knew where all the high pressure zones were, and could just perforate the oil zones (natural gas is so cheap and abundant, it's not worth producing in an expensive well right now its like $25 dollar/barrel oil). But, they hadn't gotten that far. I think (speculation) that once the heavy mud was gone, the pressure was enough to break the casing away from the cement and send it up 6 miles. > in which case you're absolutely right about the magnitude of >the forces involved and what they'd do to the cutoffs and blowout >preventers at the underwater wellhead. Unless the casing wasn't set >right, or the cement hadn't cured enough .. I think that the cutoffs were designed for the pressures encountered. But, can you imagine how hard it would be to close the cutoffs if some steel pipe were still stuck in it? I don't know that's a fact, but I do know that the cutoffs were each designed to shut under enormous pressures. It's not that hard, you don't have to push back against the pressures, just go sideways. But, if you have a big steel pipe in the way, then you have problems. Dan M. _______________________________________________ http://box535.bluehost.com/mailman/listinfo/brin-l_mccmedia.com
