Aut cum scuto aut in scuto
That's what happens. Really. I've seen it with vertical tanks. Kind of scary to hear and see.
I seen that happen with a 55gal drum and a 30hp shop vac.
A 30hp shop vac? Come TF ON!
I'm guessing he meant 3 hp, that would have more than enough suction to collapse the drum.
Absolutely. Same thing happens to a tank being emptied of liquid without a vacuum breaker or inert gas system on it. These tanks are designed to hold pressure, not vacuum. Now you know why a vac truck has a special tank construction, and can't be made out of any old tank truck.
Yes this is accurate. This was prepared as educational, note the reinforced hose no doubt connected to an unloading pump and the tank car sitting on pavement not rails. Pretty amazing.
It's real. The stresses caused by the increasing vacuum eventually load up hoop stresses sufficiently to cause just such a collapse. It happens in the P-tanks used for powdered materials in the O&G drilling industry, too.
Me - when I heard Fox "called" Arizona.
i work in a refinery. this is something we worry about every time we take a tower or vessel out of service
More likely unloading and not opening the dome lid. I worked tank haul for 15 years and would see this every now and then on a tanker that a rookie was unloading.
Mythbusters did a show on this. Their experience required a 'dent' to compromise the "structural integrity" of the tank cars they were using.However, "YMMV" - those vents are there for good reasons, "safety regulations are written in blood" (as in "Yes, enough people were dumb enough to do that that eventually some were injured, maimed, or killed. You'd think we wouldn't have to tell people ...")
Everything is fine until it isn't. I suspect we'll see that this applies in places other than tank cars.
seen it done while cleaning with steam. guy got half way thru and when he came back from lunch, was he surprised!