Argon gas regulator for ibw

By BGM dharan Date 01-30-2005 10:29

Can any one help me with some information on using the right type of Argon gas regulators for doing internal bore welding?

I find the conventional double stage regulator with ball-type flow meter (the ball is of stainless steel material) is not good enough.

Would appreciate receiving your comments.

By sparx

Date 01-31-2005 13:26

I think that you need to elaborate on the problems that you are having with the flowmeter. The "tube" style meter is actually the better design that will give you a more acurate reading than the flow gauge. I have a feeling that the problems are not with the flowmeter.
let us know what the issues are......

By BGM dharan Date 02-02-2005 09:17

1. This internal bore welding is done in 5G position by autogenous GTAW.
2. To get a bead profile without any concavity on the OD, a flow rate of 9 LPM is kept.Though this flowrate is giving good profile from 9`0 Clock to 3`O Clock position through 12`0 Clock position, it gives a convex profile in the bottom half of the weld.
3. We have found the optimum flow rate in the bottom half is about 7 LPM.
4. Is it possible to have a flowmeter which can be programmed to the welding cycle, so as the welding can be executed with flowrates of 9 LPM during the top half welding and 7 LPM during the bottom half of welding?

Thanks

By Lawrence (*****)

Date 02-02-2005 13:53

Off the top of my head, I would expect that (assumimg a consistantly good fitup) you would have better luck with a constant (but lower) purge and adjusting torch travel speed to produce the desired weld face profile.

Maybe this is something thats new to me but I've never heard of adjusting bead contour by pressurizing the pipe with argon. 9LPM sounds like more than necessary just to get a clean purge.

By backpurge (*)

Date 02-02-2005 19:57

The penetration bead should be controlled by correct parameter selection not by "pressurising" the internal bore.
This practice is potentially fraught with probems
Cheers - Bob