hers another incident , whats different was it had only 600 psi in it , ..... Cylinder Training Services. 600 PSI Cylinder Travels 1/4 mile
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There are a few details that need to be considered. For one, older tanks with older valves that have larger orifices are more dangerous because force in this situation is basically PSI times cross sectional area. Because of this, a valve who's threads fail would give the largest cross sectional area possible & the most pronounces effect.The thread name is misleading, the cylinder travelled 1/4 mile, not the valve which it sort of implies. This is consistent with the Mythbuster's test back in about 2007 or 2008. The one there went through a Bessa block (cinder) wall and smashed another one before stopping. Not sure of the pressure in that tank.
See the video .
Basic Newtonian mechanics tells us that S=ViT+1/2ATT. On the way down, acceleration is 32 feet/second squared. On the way up, F=MA gives us our acceleration. As pressure decreases, the force decreases, & so does the weight of the cylinder. This creates a fairly sticky calculus equation that I don't want to get into, so I'll just use some approximations. Lets say that the opening in the end of the cylinder is 2 square inches (which would be on the large side). 600psi x 2 sq in =1200 pounds of thrust. The cylinder was said to be around 200 pounds. 1200=200 x A Therefore, A = 6 on the way up. If we estimate that it takes 10 seconds to empty the tank (a long time for a 2" opening) and estimate that average force over 10 seconds is half of max because force decreases as gas escapes then A = 3 & T =10. Since initial velocity is zero, S=Vi T + 1/2 ATT becomes S = 1/2 ATT S = 3 x10 x 10 /2 = 150 feet traveled during acceleration. If we assume that it went up at 45 degrees (which gives the longest total travel distance) then the vertical distance is 150 x sine 45 or about 106 feet high while covering 106 feet of distance (forgetting that air has some resistance due to viscosity). At this point, we must also consider that the velocity is 30ft/sec at a 45 degree angle, and the upward component of that would be 30 sign 45 or about 21. With acceleration due to gravity at 32, rise time would continue for another 2/3 of a second, giving us another 21 feet of distance for a total of 171' so far. Using the same formulas, we calculate the fall time as roughly 170 = 1/2 x 32 x TT or TT = 19.6 so T = about 3,25 more seconds at 30 ft/sec, that only adds about another 100' for a total of like 270 feet horizontal travel or about a football field (American football), not 1/4 mile.hers another incident , whats different was it had only 600 psi in it , ..... Cylinder Training Services. 600 PSI Cylinder Travels 1/4 mile