see also: YouTube/ drochmhada/ The Gulf oil spill could have been stopped
The complete incompetence of handling the Gulf of Mexico oil spill, Macondo well, Deepwater Horizon drill rig, was astounding. The basic goalwas to stop the flow of oil, the one thing that was not done was to physically collapse the pipe. What makes this particularly pathetic is that the US government pays lots of people to study how to collapse metal structures in the design of atomic bombs.
The first goal is to remove the stem so the pipe can be collapsed in a fairly smooth manner. In 2, the arm of an underwater robotic vehicle, URV, inserts a pipe , the end of which has a ring of thermite, aluminum based, high temperature incendiary material. If the stem is 6 inches in diameter, with the stagnation pressure of a fluid being
one half the mass density times velocity squared, the radius of the stem would be 1/4 of a foot and its area would be 1/5 foot squared, allowing a velocity of 40 ft/s, 12 meters per second, seawater has a weight density of 64 lbs per cubic foot which divided by 32, the acceleration of gravity in ft per second squared, gives a mass density of 2 slugs (mass) per cubic foot, the total pressure is 1/5 ft sq X 1/2 X 2 X 40 X 40 = 320 lbs. A reasonably shaped rod and ring charge of thermite would have a pressure resistance of less than 100 lbs, the URV arm should be able to insert it. Petroleum has less density than seawater and so the forces would have been even less.
In 3, a bracket, b, is shown attached to the stem to prevent it falling into the pipe. The ignition of the thermite charge burns through and separates the upper section of the stem, freeing it for removal.In 4, charges, c, are added on the upper and lower sides of the pipe. The explosive chosen would be one with high impulse but low brissance. Impulse is the integration, roughly multiplication, of force times time.
Brissance is the ability to shatter, it is a function of the detonation speed of the explosive. For this purpose the high velocity explosives would be excluded and explosives such as ammonium nitrate and aluminum powder would be used. The charges would be used successively to flatten the pipe. The center of the top of the pipe should move down faster than the rest of the upper pipe causing the pipe to indent, not actually shown.
The edges of the bending are problematic in terms of obtaining a fully effective seal and the emplacement of a section of metal with a rounded outer edge and an ogive inner section would enable the pipe to bend around it with the metal serving as a space-filling seal. As the pipe collapses it will expand outward as pi = 3.14 and the pipe will expand by about 1/2 its diameter. That means that the filler, ogive, metal would have to be curve similarly and would have to expand with the pipe. On possibility is to have two sections of the metal joined by tubes with one couched inside of another and a strong spring internally to spread the metal sections. Extensions from the metal could protrude from the end of the pipe and hook over the end of the pipe to secure the metal in position. An other option is to place thermite charges on the4 widest section of the metal and using the ignition of the thermite to weld the metal onto the pipe.
They had months to work on this and for some reason this was not tried even on experimental sections of pipe. That means that the persons doing the work were idiots. There would be some hammer effects as the constrictions of the pipe would cause the fluid to slow, but the closing of the blow out preventer, if it had worked, would have caused a much greater hammer effect in the well. the hammer effects in the pipe section with any cracking, would not have made the situation much worse.
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