BANG! goes the weasel

You know those innocuous-looking little safety knobs that sit unobtrusively on the sides of gas cylinders, liquefied gas containers, and other high pressure equipment? They are LOUD when they blow.

We got a new Argon tank delivered yesterday with a dodgy regulator, and when the 150 bar safety knob blew I practically jumped out of the courtyard. Luckily it was downstream of the valve, so I could just shut it off, but man, what a shock. It’s a good reminder, though, that gas cylinders- even those filled with inert gasses- store a huge amount of energy and should always be treated with respect. On of the problems with a lab is that if you aren’t careful, the routine nature of things like gas cylinder swaps can potentially lull you into a false sense of complacency. Given the huge potential for harm that exists in a lot of lab equipment, that would be a bad thing. Ear protection wouldn’t be a bad idea either.

But what I’ve actually been pondering is exactly which bit failed. The reg is only supposed to put out about 80 bars or so. The safety release is rated to 150. But the gauge on my gas line was reading 105 as the blowout pressure. The fact that it got that high tells me that the reg must be busted. But I don’t know if the knob blew 45 bars low, or if my pressure gauge is miscalibrated. That’s an experiment the lads from the gas company will have to do, though- I ain’t touching that thing again, and the sooner they pick it up, the better.