I want to be able to internally purge stainless pipe fabrications, but
can't justify hiring two full size bottles. Can you buy an adaptor to
run two regulators off one full size Argon mix bottle? One to run the
TIG and one with desperate pressure control, to purge the fabrication? I
am in the UK if anyone knows who sells such a thing. Thanks.
You should be able to make your own manifold. The standard configuration
for Argon regulators in the US is a CGA580 to 1/4" NPT pigtail coming
into the regulator. A good welding equipment supplier will have 1/4" NPT
T's, elbows, and nipples. Unscrew the CGA580 pigtail from your regulator
and screw it into the T. A pair of 1/4" NPT close nipples to a pair of
elbows followed by a pair of 1/4" NPT long nipples to the regulators and
you are good to go. Use pipe dope or teflon tape during assembly and
leak test with soapy water when done.
If your gas supplier does not have these parts, Swagelock or
Parker Hanifin (sp?) will have them in brass or stainless. I would use
brass, assuming that your regulator bodies are brass.
|----------- Regulator 1
close nipples -> |
CGA580 ------| |----------- Regulator 2
This seems to be the accepted method. at least when I asked my welding
supply about purging they immediately fished out the fittings to adapt
two flow meters/valves to the regulator.
The Swagelock and Parker stuff certainly would be rated for full
cylinder pressure, and I would be pretty surprised if the gas dealer did
not carry fittings rated for cylinder pressure. 2500 PSI is not that big
of a problem for brass fittings.
The T after the regulator with a pair of flowmeters and needle valves is
certainly worth trying. It would be less expensive. My only concern on
that path would be whether the regulator could handle the vloume well
enough to keep the flow stable on the torch with the variability on the
If you look at it you are probably not using above half the flow
control capacity and certainly the regulator will supply the flow
control opened all the way. The way I have seen items purged was to
push a sponge plug in both ends, stick the hose in one end and a vent
in the other and purge till clear. After that it only takes a little
flow to keep gas inside the item.
Thanks for the replies, I have looked on Ebay UK and found a Y piece and a
second flow meter. I also found a few other bits on the site that I jusy=t
"had to have" so i have done my bit for our ailing economy, too :)
For the amount of TIG welding i do this set up was cheap and should be more
than adequate. I like the sponge idea, too, save me making umpteen bungs
and fittings ;) Will work on irregular shaped holes too, great tip!