I doubt anyone does such tests.
Remember that drillpipe is only part of a typical drill string.
The bulk of the weight on bit required to drill is provided by "drill collars", which are far more massive and thick walled even than drillpipe tooljoints.
While drillpipe is in tension while drilling, collars are mainly in compression.
If we require a shear ram to be able to cut a tool joint, why stop there? Someoene will say we must also require it to cut a drill collar. That , I suspect , would put unacceptable size requirements on the BOP stack.
I think people are putting rather too much emphasis on the BOP. Another 48 hours and they would have removed it entirely.
Good point. Somewhere you have to quit. Does that mean it cannot be improved? Since it is touted as the doomsday preventer?
Actually, I thought we(here) pretty much had determined ,as well as we can, with available fact, that safe operating procedures were not followed, and some fail-safes were not? Did you read the 'RigZone' link I provided earlier?
Way back, I said that we will never know everything concerning the incident. TransOcean's missing data for the time from 1500 till !boom, I can maybe shed some light on.
Some companies use satellite links to keep in touch with office. This data is stored until the satellite passes over, and queries for data. This could be why the data are missing. And sometimes it just vanishes. There's always a reason, though we may not know it.
Or, the NWO- mooselimb-xian-atheist- Fed -ninjas did it.
(I don't think so)
Ehocking pooh-poohed the bonus system. Which bonus do you think these guys were suspending, and why?
http://www.dailyfinance.com/article...orm-had-safety/1044363/?icid=sphere_copyright
Why things may get worse:
http://blog.al.com/live/2010/04/deepwater_horizon_secret_memo.html
Here's an interview with a survivor fairly early on:
http://www.drillingahead.com/video/video/show?id=3116006:Video:99439
And another interesting article, Times-Picayune:
If you want, read the comments ,too. I am going to go cry a little.
Begin quote:
Uh oh'
A transcript Bea collected from a witness says the companies were confident enough they had a lucrative oil source that they decided to convert from an exploratory well to a more permanent production well, a process that requires them to apply a metal and cement casing to the well hole. They chose casing 7 inches in diameter, Bea said, and that was further sealed with cement pumped in by Halliburton. Bea said his sources reported that Halliburton was using a "new" kind of cement for the seal, something the scientist said made him say, "Uh oh."
"The cement is infused with chemicals and nitrogen, and those chemicals and nitrogen form a frothy cement that is like shaving soap sprayed from a can," Bea said. "It was put in there because of the concern about damage or destruction of the seals by methane hydrates."
The crew on the Deepwater Horizon waited 20 hours for the cement job to cure before opening a key valve at the wellhead so they could place a final cement plug about 5,000 feet down the well. Bea gives Halliburton credit for writing "many excellent papers" in the past two years about the challenge of setting cement seals in the presence of large amounts of methane hydrates, which the Deepwater Horizon crew encountered in spades.
"Because of the chemicals they've added, they think the cement can cure rapidly," Bea said.
But Halliburton's awareness of cementing's challenges did not stop the cement from failing in the Deepwater Horizon's well. The chemicals they added for the curing process also create a lot of heat, which can thaw the methane hydrate into the gas that causes dangerous kicks, Bea said.
"I call that 'Uh oh' again," he said.
A heated debate described
One of Bea's witness transcripts describes in detail a heated debate among BP, Halliburton and Transocean officials as they are about to add the final cement plug to the well, 5,000 below the wellhead and 10,000 feet below the rig. They argued about whether to set the plug with drilling mud still in the well and riser, or if they should do it with lighter sea water there instead.
Oil Rig ExplosionMichael DeMocker / The Times-PicayuneA cloud of smoke that could be seen for over 25 miles rises over the gulf as fireboats try to extinguish the blaze on the Deepwater Horizon. Robert Bea said the first explosion occurred in the mud pit room, where drilling mud is mixed and stored. The two engineers ion that room were killed instantly, Bea said.
As The Times-Picayune reported last week, Bea's witness claims the decision was made to displace the heavy mud barrier with water before the final plug was set in order to finish the job more quickly.. The crew was planning to temporarily abandon the well, and before leaving, they would need to remove the riser and the blowout preventer, a massive stack of valves and slicing rams that are supposed to shut off the well in case of an emergency, and some time later another operation would re-tap the well to extract its riches.
The mud in the riser would have to be replaced with salt water before the crew could take the final step of removing the blowout preventer, or else polluting mud and chemicals would spill into the sea, angering environmental regulators. But based on Bea's witness, who describes the debate on board the rig and with officials in Houston, there was still a question about whether to replace the mud before the final plug was set.
"The debate comes back that it's been pressure-tested, the coast is clear, so they will displace the upper 10,000 feet of heavy mud and replace it with salt water," Bea said. "This is a crucial step, and the reason it's crucial is if the seal at the bottom is fine, it's OK, but if it's not OK, we're screwed. We don't have enough pressure (from mud) in the column anymore to fight the reservoir (gas and liquid) pressure."
Bea says it's unclear how far down the well the crew managed to get the final cement plug before the destructive blowout. But he said it's clear the process was under way because an important valve in the blowout preventer stack, called the annular valve, was open to allow the plug assembly pipes through. Once the well's lining or bottom plug was breached, the gas had a 10,000-foot path clear of both mud and shut-off valves all the way to the water's surface.
'A geyser of water'
Three witness reports gathered by Bea describe what happened next. "A geyser of water" shot 240 feet into the air, he said, followed by "gas that spills out in the moon pool area, onto the drill deck and begins spreading. They can smell it, they can see it, but in this stage it does not ignite. It looks like ice slush, and they can see the gas emanating from it."
The next thing workers on the drill floor saw was mud, the three accounts say. The workers know there's trouble because the mud can only be coming from 10,000 feet down, not from the riser where it can block a gas kick, Bea said.
"At this point, calls come from the rig asking for more mud," Bea said the transcripts show. "I'm certain these radio calls will ultimately be traced and produced. This is at 7 p.m."
The reason nothing ignited initially is that the 21-by-93-foot moon pool, a well in the center of the drill ship, is carefully designed to remove any sources of sparks. But in the mud room and the galley and elsewhere, there are pumps with exposed metal parts. Soon, the gas did ignite when it came in contact with those, Bea said, and the descriptions in the transcripts are dramatic.
Bea said that the first explosion occurred in the mud pit room, a room where drilling mud is mixed and stored in big bins. The two engineers responding to requests for more mud in an attempt to control the runaway well were killed instantly, he said.
That explosion also blew out the wall leading to the galley, where a party was being held.
"The party is to celebrate the Transocean Deepwater Horizon going for seven years without an accident," Bea said. Present were several BP engineers or executives, who traveled to the rig for the celebration, he said.
'Here's where I broke down ...'
"The explosion hurls them against the other wall" of the galley, Bea said. "Here's where I broke down when I read it.... It describes bodies being broken, necks gashed and people bleeding, and now everybody's in the dark. People are screaming for help. People are busy helping their comrades get to two lifeboats.
"People in the lifeboats are screaming, 'We've got to get out of here!' but the lifeboats aren't full," Bea said. "The doors slam and they drop the (lifeboats), and as they do, they can see some of their colleagues jumping into the sea. They can see their outlines because the rig is burning behind them.
"Back on the drill floor, all hell has broken loose. Explosions are propagating from the mud pit room back toward them," Bea said. "At that point, one transcript that's obviously been an observer heading toward the lifeboats says the drill floor disappears in a ball of flame. And at that point, the three on-board transcripts stop."
Bea said the concluding paragraph from one of those observing the explosion summed up the depth of the failure.
"In order for a disaster of this magnitude to happen, more than one thing has to go wrong, or fail. First, a ****** cement job. The wellhead packoff/seal assembly (the equipment directly below the blowout preventer that connects the lower pipe casing to the preventer) while designed to hold the pressure, is just a backup. And finally, the ability to close the well in with the BOP somehow went away," the witness said.
David Hammer can be reached at
[email protected] or 504.826.3322.
Mark Schleifstein can be reached at
[email protected] or 504.826.3327.
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