SS Exhaust pipe weld settings? (PowerTig 225LX)

[todmorg]

Hi Todd,

yes, the T-fitting is after the single-flow regulator. I set it up so that the backpurge valve is pulling a constant ~2L/min argon flow and when I hit the Pedal, the tig torch makes the flow meter go up to ~8-10L/min. So, my understanding is that phenomenon means that flow is going to the torch, but maybe I should raise the flow?

Also, how do you guys mount your grounding clamp to the pipe when backpurging stainless steel pipe like this? I used aluminum tape on both ends, with a slit on the outlet end and small hole for the argon tube on the inlet. But, where do you put the grounding clamp so that it's secure during this process?

How are you setting flows? Are you setting the flow at 10L/M with the torch and then throttling the 1/4 turn valve to 2L/M with the torch off? Floating ball regulator?

My table is always grounded, but I keep a 2nd cable with 2 clamps for tubing or any low amperage work. One end clamps to the welders ground clamp and the other to the tubing. This stops any arcing between the the table and tube when rolling the tube during the weld.

You can practice without backpurge and then figure out your backflows, if you keep the heat low the back purge is not nearly as important.