Smith Torch Pressure Question

[jclay]

Simon,

If the secondary (delivery) pressure creeps beyond your initial setting then the regulator's orifice valve is leaking. That while in use the problem isn't apparent is consistent with that diagnosis. That is a serious issue and I recommend you get the regulator rebuilt before further use.

[jclay]

If you follow the link to the regulator diagram, left side, you'll see parts labeled "seat assembly" and "nozzle". The inside of the nozzle has a small volcano orifice pointing to the seat assembly. The seat assy has an elastomer seat that engages the orifice and those parts constitute the valve that controls gas flow from the primary (hi press) side to the secondary (low press, delivery) side. The diaphagm, spring and other hardware control the valve movement and provide secondary pressure control. If the secondary pressure creeps up under the conditions you described then it's because this valve can't seal completely. A tiny bit of foreign matter is all that's needed to compromise sealing capability. On a regulator I rebuilt recently it looked like a tiny bit of liquid had condensed on part of the orifice rim causing a little corrosion and roughness that deformed the elastomer, making the valve leaky.

firepower250

Acetylene is unstable beyond 15 psi so you don't want to ignore the problem; get it repaired.

[Catnap]

Thank you for your help! I happen to have some brand new regulators on hand so I will just junk the faulty one and switch to the new one. In the meantime I will make sure no one uses the current setup.

thank you both for your help and advice.

[Eric Estlund]

Simon- mark it as in need or repair and get it looked at. No need to really junk it; these are meant to be repaired and that would give you a new back up.

[Catnap]

Simon- mark it as in need or repair and get it looked at. No need to really junk it; these are meant to be repaired and that would give you a new back up.

good call, no need to be wasteful! thanks again for the help.

[JLP]

I had that going on with one of my Victor regulators. I took it to a guy who rebuilds them for a living. Good as new.