"Tim+" wrote in message
...
I was surprised at how long it took before the can exploded. I would
have expected the plastic valve near the nozzle to melt quicker than
that, and maybe to cause an impressive jet of flame for a while
before
the whole can exploded.

Bloody hell, assuming it was a *full* can that must be more than a
hand-grenade's worth of energy inside a not very strong cast iron
box.

If you watch videos of fires on the news, something normally "blows" on
LPG cylinders and you get a jet of flame, insufficient to turn it into a
rocket, and the cylinder itself doesn't explode.

As the Glasgow airport "bombers" found out. Such cylinders are fitted
with
a fusible plug that is designed to melt and release the contents rapidly
rather than explosively.

Yes, that's what I'd expect to happen with an aerosol can: that the valve in
the nozzle would melt and release the contents, rapidly rather than
explosively, long before the pressure built to the point where the metal of
the can sheared at its weakest point and dumped its contents explosively.

Even an inert propellant will increase in pressure enough to make the can
rip open; if the propellant or payload is flammable, then that makes things
even more dramatic - which is what you'd think they'd want to avoid with
aerosol cans.