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NY attorney general wants vapor pressure regulations for tank cars
Regardless of whether the Reid Limit threshold was optimum (sounds like it was a WAG), this sounds to me much closer to addressing the root cause of the problem. At least compared to all of the tank car armor inch and ECP braking regs.
Maybe they should install several hundred basket ball into each tank car which could absorb some pressure as they float on top of the oil.
Mr. Cook, the problem isn’t the physical pressure on the tank car, but the tendency of vapors to form, which if ignited could cause fireballs.
And while we are at it lets require each tank car to be manned.
Each tank car could have a transmitter, giving the pressure, to be read by a trackside device!
Sounds to me like AG “Dr.” Schneiderman (D-NY, PhD in Physics?) is creating a diversion, after his outlawing some kind of football betting thingie in New York. His aspirations for being the next governor took a big hit in the polls. He has learned a lot from Sen. “Chuckie-Say-Cheese” Schumer (D-NY) and Sen. “Stolen Valor” Blumenthal (D-CT) in the PR department on things ‘railroadey’.
Wouldn’t a simple PRV (pressure reducing valve) work?
Michael J. Moss. You did not think through your reply or explain it? The problem is the space inside the tank car where the vapors can develop. The Basket balls or similar ball could fill that space and permit the car being fully loaded, and as expansion occurs, the balls would compress. The volume of space taken by the balls which would compress would reduce the internal pressure inside the tank. The balls of air or foam would be built to compress. The liquid does not want to compress. It would also eliminate the slosh that could happen with open air above the liquid. The vapors would not tend to form because there is no open space for them to form in, the space taken by the balls that would absorb a lot of liquid expansion. The oil can still be drained and tank refilled retaining the balls. An explanation where I am wrong would be welcome.
W. Cook. If the pressure in the tank car lessened as the ball compressed, what will keep the ball from reinflating? Please revisit high school physics.
Mr. Ted Kiefer Sr. from Florida, if you want to throw insults, go back to grade school. The balls fill the air space above the oil at normal air pressure while tank car is being loaded, and if the liquid expands later account higher temperature, that pressure in the tank is absorbed by the compression of the balls of foam. They do not re-inflate as they are sealed, but re-expand to normal size when the tank is unloaded. Filling the empty air space above the oil with balls prevents the gasses from leaching out of the crude oil and filling that air space with flammable gases. There is no empty air space in the tank with this loading method. And there is no slosh or oil movement.
They should put flares on the cars, with an igniter, so when the pressure builds a nice flame blows out the top of the car. That would look real neat at night, a train of torches.
Actually, the balls would not reduce the pressure. The pressure would stay the same but the gases would fill the volume that the balls had before they compressed. At a certain point, the balls being fully compressed would no longer allow the outgassing vapors to expand and the pressure would again increase.
And would set fire to bridges, electric lines, phone lines, trees, etc… Not a good idea.
At a certain point……fully compressed would no longer allow the out-gassing vapors to expand and the pressure would again increase.----- At that point the car has reached destination. If the travel was longer, next trip increase the amount of compressible bladders. Insertion of compressible bladders within hydraulics systems has been a common practice to prevent damage from hydraulic hammering.