Question... I have an old acetylene regulator, that seems to still work, but both the high and low pressure gauges are trashed. I also have a handful of other regulators (got them cheap at an auction), that I believe must be for carbon dioxide or argon, because of the flat faced connections where they'd hook up to the tank. Is there any problem with using the gauges from the non-flammable gas on the acetylene regulator?
Good question, one I've never thought about and have no knowledge about. And using that ignorance as a legal disclaimer (don't do as I suggest), my first thought would be that I don't thing the gauges matter whether it's flammable or non-flammable gas. However, acetylene gauges display at a far lower pressure in comparison to other high pressure cylinder gasses, especially on the high side gauge. Doing a quick search for "welding gas replacement gauge", I found several welding parts suppliers that offer replacement gauges of different pressure, none note being specific to type of gas. Given that, as long as it's a gauge from some form of welding gas regulator, I'd say it meets the proper specs for your application. Just my opinion.
Yeah, i guess I have to agree with Willie again. Like he said, the high side guage is usually 500 psi, and the low is 30 psi. Acetylene becomes unstable at pressures above 15 psi. I wouldn't worry much about acetylene, but I'd buy new guages for oxygen, because of the danger of contamination. (Besides, if it does blow up, me and Willie won't even be able to hear it this far south.) New guages can usually be gotten for less than $10, anyway.
Yes, if there's any oil at all in the confines of an oxygen regulator/gauge, it will cause rapid combustion within the regulator when tank valve is cranked open.
Willie nailed it as usual.:notworthy Like he said, just buy some new acetylene pressure gauges, they are not that expensive and will have the proper range to work with your acetylene regulator.
Don't know over with guys in the US but here in the UK we have left for fuel gas and right for non-fuel gases, so wouldn't fit here. I have used used argon reg on an oxygen fine.
You could've stopped right there you know. :tong Actually, I have one new gauge, that I bought years ago and never used. It goes to 600, so it must be for the high pressure side of the acetylene regulator. Of the other old ones I got most of the low pressure ones go to 50. I have a brand new set sitting on the counter right behind me, and the Oxygen goes to 3000 for the high side, and 150 for the low side. The acetylene goes to 400 and 30, respectively, and, as Mitch would suggest, there's a big red shaded area for anything above 15. So the question is whether one of the ones that reads to 50 would be appropriate for the low pressure side of the acetylene gauge. I hadn't thought about the thread direction on the gauges. The hoses and connections to the bottles themselves are right and left here, as well. I just checked, and the gauges, even on the acetylene regulator unscrew right handed, so they seem to not be specific to fuel/non-fuel, at least as far as thread direction goes. I may have to look into that. One of the old ones I got has gauges that read in the same range as the Oxygen gauges, but the connection to the bottle has a flat face. (I'm correct in thinking that's for Argon, right?) I'd need to change the stem to one compatible with Oxygen. (And they say "Use no oil" on them. I'll check them out real good before I connect them to anything.) Yeah, but if he thinks I'm taking his advice he'll get all big headed.....
Wait a minute, don't bring my head into this, it gets me in enough trouble already. I don't see any reason you couldn't use the 50 psi gauge for the low side of acetylene. It's graduations would only be a little different. As long as you can use the graduations to set the low side to between 8 and 12 psi you should be fine. The "use no oil" applies mainly to oxygen. If you pop open the hand valve quickly, that causes rapid compression of oxygen within the regulator. If there's any oil inside the regulator components, this rapid compression (generates heat, source of combustion), the oil (source of fuel for ignition) and the oxygen (oxidizer) just like what fires a diesel engine. Goes downhill rapidly with an oxy regulator.
Wille's exactly correct about the oxygen gauges. My high pressure oxygen gauge broke so I grab a used one I have and install it. Well the second time I use the tanks the gauge blows up. I'm lucky I got hit in the eye but did no damage. I must have used it years ago to check oil pressure on something. Stupid!! Since then I've read any contamination can do the same thing. Everyone looks at the gauges when they turn them on. Now I look away.