There have been a few times I was glad someone invented the blowout preventer (BOP). One was on a Gulf of Mexico gas platform in the late 1970s during the workover of a high-rate gas well. The well got real nasty on us after we returned from a hurricane evacuation. Hunkered on the boat deck in high seas and pitch black trying to figure out how to get off the platform that look set to launch itself to Mars, the only thing that mattered to us was that the severely strained BOPs would hold long enough. I am still here, so they did.

Another time, we hit the accumulator lever after a swift, 54-barrel pit gain on an inland-waters well. They closed and held.

I could go on, as could most of you.

At the time, we didn't really give much thought to the function of the BOPs, or their design evolution. We just expected them to work, and they did. I think that is the way it is with most of us and the technology we use. Every once in a while, we need to be reminded that we employ some really unique, complex and reliable equipment whose proper functioning protects lives, the environment and enables us to operate efficiently.

Thanks to the American Society of Mechanical Engineers (ASME) I was recently reminded of what a unique and important piece of technology the BOP is. That is because the ASME has designated the Cameron MO BOP an ASME Historic Mechanical Engineering Landmark. Hats off to ASME. We need more such recognition of the role of technical innovation in the oil and gas industry.

The MO preventer, the first ram-type BOP, has a fascinating history. Initially marketed in 1924, the MO solved some thorny, and dangerous, problems. Despite a number of attempts, no reliable method had been devised by the early 1920s to cap wells as they "blew in." Probably the best known example of uncontrolled well flow occurred in January 1901 when Captain Anthony Lucas' well "blew in" near Beaumont, Texas, ushering in the American oil boom. The well, cased to 880 feet, blew out at 1020 feet. The drillpipe was blown out of the hole and a "geyser" of oil erupted some 100 feet into the air. Estimates put the flow as high as 80,000 b/d of oil, by far the most prolific flow seen to that time. The well blew for nine days before it could be capped by hand. Hastily built dikes contained the oil, some 500,000 barrels, in large pits until the well was capped: several days later, the oil caught fire and all was lost.

The story was repeated countless times as the US oil industry developed. By the late teens and early 1920s, drilling in high prospect areas was so intensive that rigs, built of wood, were literally spaced yards apart. A fire in a pit, or wooden tank, close by sometimes meant the destruction of dozens of rigs. And, of course, the environmental damage was enormous, as was the sheer waste. There was a clear need for a device that could immediately stop the uncontrolled flow of wells.

Jim Abercrombie, a Texas oilman and drilling company owner, and Harry Cameron, a well-known south Texas machinist, decided to tackle the problem. Abercrombie came up with the idea of a ram-type preventer "with the faces of the rams (simple hydrostatic pistons) closing on the drill stem to form a seal against the well pressure."

"Abercrombie took his idea to Cameron and the two worked out the details of the design drawing in the dirt floor of Cameron's machine shop in Houston." When finished, they had the design for a simple BOP composed of a "minimum number of parts of simple and rugged construction." The key to the success of the MO BOP was in the packing. The rams "incorporated an ingenious V-shaped notch in one of the faces near the corner. This notch, when placed in the direction of the fluid pressure, opened, forcing the thin lip against the sealing surface . . . this cross-sectional configuration allowed the MO packing to hold 3,000 psi of pressure, an industry record at the time. Tests and improvements on the basic design extended over two years and in January of 1924, Abercrombie and Cameron began to market the MO." By 1925, the BOP was in use over south Texas, Mexico and Venezuela and the original cast iron parts had been replaced by steel. A patent, applied for in 1922, was granted in 1926. The MO BOP stood just 26 inches tall and weighed only 1,380 pounds.

The BOP's design has stood the test of time. Although today's subsea BOP stack may weigh 300 tons, stand 60 or more feet tall, and be rated to 20,000 psi of pressure, it still relies on the same ram principle as the original MO. During the design's life and numerous improvements, countless lives and untold equipment have been saved. Environmental disasters have been continually avoided. And the efficient development of the oil and gas industry has continued. For that, the Cameron MO BOP deserves an award, as do many other of our innovative technologies. Hopefully further recognition will be forthcoming.
Oh, about that gas platform that was going to turn itself into a Roman candle. The well bridged over about 12 hours after we evacuated. Not by boat - the seas were too rough. Not by escape capsule - it was too rough to launch them. We went by field helicopter, three at a time, with a pilot who was breaking every rule in the book flying in the dead of night without IFR instruments. Best pilot I ever flew with.


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