selecting proper mig wire

By hadi Date 02-01-2006 08:46

I want to select solid mig wire for automated welding of "X70 grade" pipeline based on API.
The pipe is 56" in diameter and 1.4" in thickness.
As the standard say for this base metal, I should select the wire to reach tensile stress more than 565 MPa.
I want to know is it adequate to see only the tensile stress that the producer of mig wire mentioned in his catalogue, or there are some more notes to be attended.
One producer suggested me wire with Ni-Mo alloys with 700MPa tensile stress. this is too more than what is needed.
How should I select the proper wire?

many thanks to your answers.

By nimajavidan (*)

Date 02-01-2006 11:22

Dear Hadi
As u know minimum tensile of API 5L X70 is 565Mpa
so u r supposed to choose ER80S-6 which has same strength and high oxygen removability.

By hadi Date 02-06-2006 06:34

Thank you for answering to my question.
My problem is that ER70S-6 support 565Mpa tensile strength.
Why you have suggested ER80S-6?

By nimajavidan (*)

Date 02-06-2006 11:22

it is not true,
ER70S has maximum tensile of 70000 psi that is equal to 482 Mpa
So u r not able to use this filler metal.

By qiaoshf (*)

Date 02-07-2006 07:39

What do you think of ER80S-B2 which contains 1.2% Cr and 0.5% Mo ?
It can reach 550MPa at least.

By George-kh (**)

Date 02-07-2006 12:36

There is not any NACE requiremnet in your spec.?