PGMAW

By Lawrence (*****)

Date 11-04-2005 16:32

Assuming PGMAW is synonomous with Pulsed Mig--GMAWP (love those acronems) It's reasonable to see why it's called out.

A 72' dia. cap is a lotta milege for GTAW. Especially if you have alot of them to do. The Mig Fill passes are economical, with what, about a 10x deposition advangate over Tig?

The SA-240 is a 300 series stainless I recall, but no super special heat input sensitivity to require GMAWP over Traditional Spray transfer unless material thickness is below 0.125 in and your worried about burn through. But your issues being lack of fusion suggest that at least a little more heat wouldn't hurt. The only other real advantage to GMAWP is the ability to get a spray transfer weld out of position. If your operation has this requirement than thats another reason.

What type of pulsed GMAW power supply are you using?

Is your pusled mig operation manual or automated?

Is your pulse equipment synergic?

Groove or Fillet?

Material thickness?

There are about 4 generations of Pulsed Mig technology out there and each generation has specific parameter issues to be dealt with in order to get good production..... However, some older GMAWP power supplies were never able to perform as advertised.

By NEQA

Date 11-04-2005 18:22

Thanks Lawrence - do not know the type of GMAW power supply being used - but based on your comments, I will find out.

Base metal is .1875" to 1.5"; position is 1G; PGMAW semi-automatic; joint is single or double bevel.

By jwright650 (*****)

Date 11-04-2005 20:45

Personally, I would turn off that pulsed feature, and use straight GMAW if the material is 3/16 - 1 1/2" thick.
John Wright

By Lawrence (*****)

Date 11-04-2005 22:25

Amen.

Why diddn't I just say that :)

If the WPS calls for Pulse it can't be prequalified. So if you switch the pulse off does that mean requalify the whole kaboodle?

By NEQA

Date 03-30-2006 18:49

This monster is rearing it's ugly head again. I am thinking that if I have them switch off the pulse, they will have to re-qualify their WPS. Agreed?

By GRoberts (***)

Date 03-30-2006 20:23

Not if you are using ASME IX for qualification. Transfer mode is not an essential variable except when switching to of from short-circuit mode.

By billvanderhoof (****)

Date 03-31-2006 09:07

I've never even seen one of these new fangled gadgets but (assuming this is all possible) suppose that instead of turning off the pulse thing you set it to produce square waves 99% high power 1% low power. For all practical purposes it's off but from a lawyerly point of view it's still on.
Bill