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Up Topic American Welding Society Services / Technical Standards & Publications / metal core
- - By hogan (****) Date 12-07-2007 00:01
our shop is looking at running metal core. from what i have been told, in 2008 d1.1, that it is a prequaifiied process and all i would have to do is qualify my welders. this would not be the first time someone trying to sell me consumables told me what i wanted to hear, not what was accurate.anyone have any info on this?
Parent - - By Lawrence (*****) Date 12-07-2007 00:23
Metal Core is considered GMAW now (D1.1 2006)  So as long as you are running spray transfer you could write a pre-qualified WPS right now!

It would be a pretty major change for them to declare it a new process for next year........  Don't really know anybody on the committee though.
Parent - By hogan (****) Date 12-07-2007 14:01
thanks
Parent - - By pax23 (**) Date 12-07-2007 19:34
Metal core was originally categorized as FCAW many, many years ago. I believe it was in the mid or early 90s that the A5 Filler Metal Committee reclassified metal core as GMAW wire.

Metal core has been considered a prequalified for many years and many D1.1 editions. It shows up in Table 3.1 in the filler metal requirement's column.
Parent - - By Bill M (***) Date 12-17-2007 18:48
I have used the metal cored wires in overlay applications a while ago -so I am not current at all ...but have a question.

Is using straight CO2 considered a short circuit transfer then with the metal core wire?
What shielding gas do you need to get the metal core wire into a transfer mode to be considered prequalified?

thx
Parent - - By Lawrence (*****) Date 12-17-2007 22:01
Good question Bill

Trimark posts paramater guidelines from 75-95% argon balence C02
http://www.hobartbrothers.com/pdf/datasheets/Metalloy70X.pdf

They say it can be both short arc and spray...

I would hazard to speculate that the same gas mixes for solid wire would probably produce similar transfer to the cored wires.....

If it sprays you ought to be able to see the pinch effect ..... Not very scientific but hey... D1 considers cored wire and solid wire pretty much the same anyhow.
Parent - - By rvarpazos Date 12-17-2007 22:08
Spray transfer with metal cored is very easy with a 80-85% Ar and 15-20% CO2.
Parent - - By Bill M (***) Date 12-18-2007 13:33
We have either Straight CO2 or we also use a lot of C25 gas here.  I am trying to avoid a third bottle gas variety, (yet stay pre-qualified).

So if I need 80% minimum Argon to spray transfer the metal cored wire, what transfer mode will the 75% Ar, 25% CO2 gas give us?
Parent - By petty4345 (**) Date 12-18-2007 13:51
It's been a while since I ran that but we used 75% Argon/25% C02 and it "appeared" to be spary transfer.
Parent - - By rvarpazos Date 12-18-2007 21:56
75% Ar  is enough to get spray transfer with metal cored.
Parent - By welder5354 (**) Date 12-23-2007 05:51
Using 75/25 with Metal Cored is that u will get more worm holes, porosity and a lot more smoke.
The best mixture is 85-90 argon and the rest CO2.
My preference is 90/10 with .045 wire.
Up Topic American Welding Society Services / Technical Standards & Publications / metal core

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