I missed the staff meeting but the minutes show Ian Stirling
wrote back on 26 Jan 2005 18:50:11 GMT in
rec.crafts.metalworking :
pyotr filipivich wrote:
I missed the staff meeting but the minutes show "Glenn"
wrote back on Sat, 22 Jan 2005 16:15:27 -0800 in
rec.crafts.metalworking :
I hesitate to jump in here as my knowledge of the subject is limited to
reading, but IIRC the problem lies in the superheated water in the
container. The pressure allows the water to be heated to well above boiling
point at atmospheric pressure. When you release the pressure as in opening
the steamcleaner valve, all the water can now turn to steam very rapidly.
If your popoff valve does not have sufficient capacity to dump the excess
pressure fast enough the vessel can become overpressured and turn into a
bomb. Seems there was also a greater problem as the water level gets down,
the flash over can occure more rapidly.

For the "Rube Goldbergs" among us, it shouldn't be "too difficult" to
rig a water quench on the steam tank. That is, when the "Oh ****"
pressure valve cuts loose, it trips water reserve, which floods around the
boiler, which "should" soak up heat from the boiler, and hopefully lower
the temp enough to keep the superheated water from trying to become steam.
Or just lower it back to "really hot water".

Me, I'd be tempted to dig a biggish hole, and place boiler inside.

Good idea too. Tends to channel any explosion "up and away".

Or you could take a tip from the gun powder mills or old powder
magazines. Three stout walls and a flimsy fourth and roof. That way, if
the mill blew up, the blast goes "that way" in stead off "everywhere."

--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Niccol wrote "It used to be that the USA was pretty good at
producing stuff teenaged boys could lose a finger or two playing with."