using gas welding regulators for propane

Al,

I've been running an acetylene regulator on a propane tank for the last 8 years firing my melting furnace - no problems what-so-ever.

Andrew Mawson Bromley, Kent, UK

Thanks for the info. On to the next step, finding the old regulators in my garage:-) I know I have some or at least one somewhere.

Al

Well, all the plumbing for acetylene is Left Hand Thread, and all the plumbing for poopane is Right Hand Thread, but other than that...

Charly

Charly,

That is NOT the case in the UK - fuel gases are all lh threads - cannot speak for far flung remote parts of the Empire where odd habits may have sprung up !

Andrew Mawson Bromley, Kent, UK

Not in the US, propane tanks aren't RH threads. No way, Jose.

I just took my acetylene regulator off my tank and threaded it right into the propane tank I use for my forge, just to make sure. Perfect fit.

Grant Erwin Kirkland, Washington

I have no idea - I've often wondered.

I've got official BOC instruction leaflets here saying both that their acetylene regulators may be used for LPG, and that they may not be ! I can only assume that it's age / model specific.

BOC's flashback arrestors may be mixed around though (if you're using a torch too). Some of the (the large resettable 35+) older ones don't have enough flowrate to run a large propane burner, but the current model claims to. The small non-resettables don't have enough flowrate.

Fittings OTOH are easy - they're all the same for either gas.

Then where did the one I've got come from? RH thread and no mistake. It's old, but I didn't think it was THAT old.

I'm having a helluva time parsing this without the punctuation.

I've used my acetylene regulator for propane. Sure appeared to me to work.

Let's see. 1.5 bar is about 22 psi, right? 4 bar is about 58 psi, right? I think Carl is saying that a propane regulator can regulate to higher pressure (although I've never heard of anyone using propane above about 30 psi, it costs too much) and can deliver a much larger flowrate as well. That's how I parse it, anyway.

Grant Erwin

There are two questions; does it work, and should you be doing it ?

"Does it work" is a question of flowrate. I often use a 6" long oxy-propane flame-cleaning line burner and I _know_ that no acetylene regulator is going to feed it. The smaller propane regulators can't cope, and I can manage to ice up the propane cylinder even in the height of summer.

"Should I do this" is a question of materials compatibility. LPG shouldn't be run through acetylene hose, and many of us are wondering about similar questiosn regarding the diaphram and seals.

This was my original concern and why I started this thread.

Things that I think I have learned from this thread:

1) Check handiness of hose. I just checked and my propane hose has left-hand threads. I know the regulator is left-hand threads.

2) determine pressure needed. From studying other forge burner sites it seems that 15-20 lbs should be plenty so the

1.5 bar or 22 psi that seems to be normal max for acetylene regulators should be ok.

?? how about the volume of gas delivered.

I still need to go home and find the regulator and check the gauge. I think I remember that the gauge goes beyond 20psi.

I'm hoping that the diaphragms and o-rings hold up.

I guess I could change the o-rings.

Should be o-rings be made of a specific material or would any o-ring that I use in the car be OK.

Changing the diaphragm sounds hard.

Does anyone know the actual rubber or rubber-like material that would be correct for propane use? and how would I if I had the right stuff.

Thanks to everyone that told me they have it working. It gives me hope. What brand, model or year regulators have you found to be useful.

I'm sure there is a big difference between one made by victor a long time ago and one made today in cheapistan by the tie-eye-wan company. Al

There are propane regulators which will work for a forge. I have a Fisher (?), which goes up to around 35psi (way high) and cost about $50 bucks a few years ago. I think I've seen similar for around $35 recently. Your local gas supplier/welding shop should sell them.

don