steel fittings with argon ok ?

[ttype]

Am adding a T in my tig gas line for a pipe purge.
Is using steel fittings with argon ok ?
All fittings are presently brass, so want to make sure the steel fitting will not corrode, react, explode etc

Looks like the fitting is cadnium coated.

Thanks

[fun4now]

i would be concernd about it seating properly. whatever you do, DO NOT use plumbers teflon tape in it to get it to seal.thats a big NO NO. it would be best to get the proper T, you should be able to get one at your LWS no problem. if not just get a brass hose T and install it after the regulators in the gas line going to the back of the welder. just cut it and splice in the T and add a 2nd line for a purge. would be a good idea to add a shut off valve in the purge line.

[SundownIII]

Brass hose T should be readily available at your local home supply outlet. HD or Lowes (don't know if there're in Canada).

Sounds like one way to go, rather than having two regulators. However, I question how well it will work for back gassing. Seems to me, you're going to have a lot of trouble controlling the flow. If the regulator is properly set for a combination of welding/back gassing, seems that when welding is complete and postflow is done, you're going to have twice (or thereabouts) the amount of gas flowing to the backgassing. Just something to consider.

I agree with Fun that you need some form of shutoff on the backgas line. Even then, I don't think it's the right way to go. Dual regulators are more expensive, but the way to go (in my opinion).

[JonnyTIG]

Steel fittings work fine. You can mix brass and steel / coated steel no problem. You wont have any problems with contamination or any sort of reaction. Shielding gas does just that. It shields metals from oxidization, welds, fittings, what ever you use.

[ttype]

The fitting coming off the regulator was sealed with a thread compound.

Had planned on using teflon tape for the connections, as the steel fittings dont give as much.

Whats wrong w teflon tape & argon ?

Teflon tape gets a bad rap for plugging orifices up, but a tired muddy farmer applying to much tape & plugging up a hydraulic valve is a different situation.

Reason for steel fitting , is they come in alot more choices. Ones with male ends shorten the settup by an inch.

Have a needle valve off another reg so should be able to control the flow quite well.

[calweld]

I think what Fun was referring to was the use of teflon on seated hose fittings . . . if you have tapered pipe fittings, proper thread sealant/teflon tape is essential, both for sealing and for eventual disassembly.