Purging parts

ok so ive had the hf inverter a while now (IFL 200 hf) and ive managed ok with the supplied twin gauge regulator , but will need to do some purging on stainless tube fittings ive got to weld up .
so today i bought theses bits

thinking about it tho i think i need another flow meter to go to the welder or would it work ok just using the purging line with the one flowmeter

oh and approx what flowrate shoulsd one purge at , ? or is it just suck it and see

cheers mike

If you know what flow you're getting through the pea shooter, and you know what you want at the torch, just add the two together and set that at the regulator. For better precision, put the peashooter to the torch line, and add the purge lpm to get the total.

If that's not clear , say you want 7 lpm at the torch, and ten to purge, set seven on the peashooter, 17 on the regulator, and ten will go to the purge.

Depends what you're doing as to what purge you need!

Thanks si , yep i understand that ,although my maths never was brillient
If i have a mental block another flowmeter is only £14 or so

cheers mike

Like that flowmeter! Where did you get it?

For small jobs I've been known to use a disposable cylinder (regulator borrowed off the mini MIG) for the purge.

Hi , i got the bits from my local(ish) supplier www.telfordgroup.co.uk
there not listed on the website tho .
The tee piece with the two valves was about £20 ,as i said the flow gauge £14 plus a hose tail ,lemon clip , hose etc so it all adds up

Im sure weldequip or any other decent shop would have them too

cheers mike

Mikey D said:

oh and approx what flow rate should one purge at , ? or is it just suck it and see

cheers mike

Click to expand...

Hi Mike, flow rate for purge will depend on tube/pipe dia. Personally I Would have the peashooter at the purge end, reason for this, as you begin to close the weld, you will require to back off the lpm flow rate, say about 2>4 lpm. Reason for this, as you close, pressure from purge will build up pushing out the root.

Re: suck it and see, again depending on wall t, if you have a gap, do the purge for a few to fill area with argon, then back off to around 8 lpm and, if gapped, try to see through the gap to view if root is coked up, if clean, should be fine to continue.

What are you using for dams? Also depending on gap and pipe dia, handy to tape up around the joint, peeling back as you progress, helps to eliminate the atmosphere outside flooding and coking up the root. Have to emphasis, all of the above is depends on pipe dia?

HTH n cheers...........

Mikey D said:

Hi , i got the bits from my local(ish) supplier www.telfordgroup.co.uk
there not listed on the website tho .
The tee piece with the two valves was about £20 ,as i said the flow gauge £14 plus a hose tail ,lemon clip , hose etc so it all adds up

Click to expand...

It's just so nice compared to my old medical salvage Oxygen one! And, then, to weld this Ti pipe I'm going to need 3 of them.............

Hi runnach , thanks for the reply some usefull info there
its basically some assemblys with non return valve ,short length of 40mm pipe a 1 1/2" - 2" reducer and 2" RJT union the wall thickness is about 1.5 mm . so no gap

cheers mike