I was first inclined to think, "No... that was just a loose cylinder" until
I saw the evidence of fire and the ruptured tank.
This was probably caused by friction: Some folks have surmised there may
have been oil or grease in the valve. That's not likely, even if the guy
was dumb enough to squirt some PB or Liquid Wrench on the valve. It
probably would not have gotten past the thread seals. It MIGHT have gotten
exposed to O2 if he had the valve loose enough. They didn't say anything
about the application of a rust-breaker oil, though, and I think they would
have, if that had been the case.
However, a tightly installed pipe thread engages metal-to-metal, even with
sealant present. Wrenching a threaded component apart always causes extreme
friction until the taper relieves the fit. Some metal would have been
abraded away as a fine powder, along with the generation of enough highly
localized heat to initiate combustion.
Once the fire started, it was self-sustaining. Then the O2 pressure (likely
above 2500psi to start with) rose high enough from the addition of heat and
combustion products to rupture the tank.
That slide show is definitely not breakfast fare.
At STP, most metals become pyrophoric at sizes smaller than about 1000 mesh
(around 0.5 micron).
I don't have the tables on it, but I'd guess that pure pressurized O2 would
lower that to more like 300 mesh.
Such small particles are the normal result of friction between threads.
That said, there WOULD be very high localized heating, so the two together
are almost a "gimme".
And if the tank was empty - there would not have been the massive oxidizer ready
Drain down the tank and fill with water.
Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH & Endowment Member
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member
Pete C. wrote:
But Martin, that's the whole thesis of this accident review... He COULDN'T
drain down the tank. The valve was either frozen or broken -- so he
intended to just loosen the fitting, and let the tank drain that way.
And that's a big mistake.
In the Navy, if a tank top was damaged in any way whatsoever, the whole tank
got AXED in our guillotine "tank disposer-of-er". Cam Rahn Bay got its
share of empty tanks with no valves...
Now, the military is a lot more cavalier about throwing away money than a
civvy company would be, but in this case, they should have a policy in place
to waste a little to save a lot.
I'd bet that hey have killed or injured far fewer people than, say,
light fixture falling off ceilings.
Don't grease them, dont try moving them about without the cover over
the valve, don't do stupid shit like trying to remove valves while they
are under pressure. You'll be fine.
Figure out the explosive energy potential in the gas tank of your car,
if you need some perspective.
Then you can try to find a nice couch to hide under while you try to
I know that. Now I wonder the next time I turn on the valve at work
if the guy that set the tank followed all of the above precautions.
What if some clueless idiot put grease or oil on threads not knowing
better and I'm the first to crack the valve?
It is pretty fair. Just bought 5# of black powder as part of a group
buy. Got it for 11.00 a pound. It still is in the trunk of my car.
I bet my little Saturn might have a chance to get close to its
namesake if a fire broke out.
My couch isn't that sturdy and I've gained a few pounds. Have you
kicked your dog today or did he bite you?
Five pounds of BP will lift an 120 lb. fireworks shell approximately 1000'
high (out of a fairly close-fitting mortar).
SFX guys use two to five pounds with a "pole cannon" to roll cars at speed.
Five pounds would definitely blow all the windows and the trunk lid. It
would probably also "alter" the basic body shape by inflating it. But I
doubt it would disintegrate the vehicle. The ensuing fire would, though.
On Wed, 01 Nov 2006 15:44:54 GMT, "Lloyd E. Sponenburgh"
I had a tech working for me who spent $3000 ordering ammo components
over lunch about a week before Y2K. He had 140# of smokeless sitting
in his living room. He moved on to another job not long after.
I got my all time favorite quote from him: "I believe the best value
for your entertainment dollar is gasoline." That was said with a
completely straight face. This was when I lived in Texas, not
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