Re: propane gas tanks ballistics?

The men are in no danger really, unless something very hard hits the tanks going very fast. these tanks are made of very strong materials, and with all the pressure inside, it's very hard to put a dent in one of them even without considering the strength of the metal itsself. if the valve at the top is knocked off cleanly, the cylinder can become a ballistic missile capable of punching through cinderblock walls, but that break must be clean to ensure that the tank won't spiral off in some random direction. as for grenades, they are designed with specific weak areas in the body so that the metal its comprised of will shatter aand send as much twisted metal in all directions as possible when the explosives detonate.

Propane tanks generally aren't tall and slender, so maybe what you are seeing is oxygen nitrogen or argon cylinders being rolled across. These cylinders are thin and tall by design. These gases can't be liquefied at ambient temperatures so they compress them to about 3000 psi to be able to hold a decent amount of gases. This way they can fit about 300 cubic feet of gas into about 2 cubic feet. Otherwise the customer would be ordering new cylinders every hour.

Those cylinders are very heavy and made to withstand high pressures. They also put steel caps over the top valves so if they fall over, they won't break off the valve.

Even if they rolled one over without a cap, and the valve accidentally broke off, it wouldn't explode since it is just escaping gas. I t might be like a giant bottle rocket for a second while the gas escapes and you wouldn't want to be in its path.

Even the oxygen wouldn't explode. To explode you need two things 1 a fuel and 2 a oxidizer.

Oxygen is a oxidizer, but without being mixed with a fuel, it won't explode.

Same goes with propane. If these cylinders were propane, first off they are liquid under ambient pressure, so the steel holding these tanks doesn't need to be thick because the pressure isn't very high, usually under 100 psi even in 90F heat.

But even if the propane leaked out it would boil away, and not unless it mixed with air and ignited would it burn, and it would be just a big whoosh , more than a explosion

Grenades contain the two essential ingredients to a explosion... a oxidizer and a fuel. Plus they are jacketed with a steel container that holds in the gas pressure from the internal explosion ( with a oxidizer the fuel instantly burns inside the grenade) and doesn't explode until the designed jacket fails. This is done on purpose. You will see little cut block lines all over the grenade surface. Since it is mostly spherical, the grenade breaks up at all those cut places ad the force is radiated out equally.

You can probably go on YouTube or Mythbusters to actually see someone actually cutting off the top of those welding cylinders. The movies are greatly exaggerated. The pressure is great inside those cylinders, but it very rapidly goes down when the top is let off and probably around a second or two , it is empty

To the point of one of these high pressure tanks has the valve knocked off. Mythbusters did a test on one of these tanks. When they knocked the valve off it rocketed through a cinder block wall.