D1.1 Welder qual on mismatch base metal/electrode class

Date 12-04-2015 15:26

Under D1.1, can you perform a welder qualification test plate with A36 steel using FCAW A5.26 E111T1-K3M-JH4 (Lincoln ULTRACORE PLUS) without using RT?
Would I be in conformance using 2-1/2" dia. plunger for bend test for the high high yield wire (or is this strictly for base metal as stated in the bend test jig figure)?

By jwright650 (*****)

Date 12-04-2015 16:15

Does the welder already hold certification that was tested per Clause 4 in D1.1?
If so, I wouldn't retest him/her unless the EOR has requested the retest or unless they haven't used the FCAW process within the last 6 months.

I've been asked to mis-match base metal and filler like that before and in my mind the base metal wants to give up first due to shrinkage stresses that build up and overcome the base metal strength. I can understand a slight over match of filler, but why do people insist on these larger mis-matches? What are you gaining by mis-matching like this?

By dbrizor (*)

Date 12-04-2015 16:28

Thanks for the reply.

No, they do not already hold a FCAW qualification.
In production the filler metal is matched to the production base metal and they use no other FCAW classification electrode to do tests on. They also do not have test plates of this material though but rather A36. Hence the mismatch test specimens.

I tried some test bends with 1-1/2 dia plunger but all fractured at weld with no indications of voids or slag inclusion. That's why I was wondering if a larger plunger would be acceptable under these variables

By jwright650 (*****)

Date 12-04-2015 16:55

I would expect those fractures to be right at the base metal/filler metal interface.

If it were up to me, I would purchase a small roll of E71TXX or E70TXX just to perform welder quals with. If you are running 1" coupons, you'll use up the wire in a reasonable amount of time. Your local electrode rep may even have a spare roll to give you if you are already purchasing large quantities of their products. Just a thought.