Hi. I bought a brazing torch set and found that the valves are a little sticky. It is a National 3A torch. What do you recommend for greasing the valves to free them up? I would be tempted to use Black Swan, but this might not be safe. The welding supply sells Krytox, which is definitely oxygen safe, but this is $81 for a 2 oz tub (enough for hundreds of torches). Dupont 111 might be OK, but it is not recommended for liquid oxygen service. Somebody suggested silicone high vacuum grease. I suspect that any of the non-petroleum based greases should be OK for low pressure oxy service, but its best to be safe.

If the welding shop repairs torches see if you can get them to dab some on your parts if youi have them dissassembled and take them in...May have to pay a minimum fee but that beats $81

mixing the wrong grease with oxygen can cost you more than $81 use only a grease that is approved for oxygen service and don't guess at it. This is not the place to go cheap. The wrong grease + oxygen can result in fire or explosion.

Woody

i dont know the type you have ,but we use flake graphite the stuff for yale locks

Hi fellas. Thanks for the advice. It's very helpful. I disassembled one of the valves and found out that it has an interesting configuration for a needle valve. There is the usual needle, the usual driving thread, packing, and a top thread on the packing nut. The last one is where it is corroded and binding. There should be no oxygen up here, and I would be a huge slob if I left one milligram of flake graphite up there. A microgram would probably suffice, and the hazard of that at 6 psi oxygen in the lower part of the valve is very small. I found out that Black Swan is not really silicone grease (it is silicone bearing) and is therefore not safe for oxygen service.

I drive a truck and deliver dangerous goods.If we use any oil on the straps we get a real blast of XXXX. Any oil in contact with oxygen from the tank can and probably will result in a fire ball. I have picked up torches and regulators that have blown up in the man's face. Be careful........Tim

EV,
Why don't you just send that 3a to me. I'll take care of it for you. Or... Actually, my wife will. She uses that same torch for lampwork and beads. Maybe save me from having to buy her another one since she hates changing the tips...

ML

Here is what I have. Look down the page for Cristo Lube. $17.50 for a half ounce. Good welding supply store should give or sell you a little dab of what they have though.

Dive Rite RG2500 Regulators...Performance and Reliability