Qualification of wps as per aws d1.1

By santosh Date 03-25-2015 04:19

I want to qualify a WPS as per AWS D1.1. I am using SMAW process and E7018 electrode. I cannot use pre qualified wps because both the materials are not listed in AWS D1.1 code. That's the reason I am going for qualification of procedure.

Both the materials are carbon steel and have some difference in mechanical properties.Since both materials are not listed in AWS code i cannot do the grouping as well.The two materials to be welded have mechanical properties as follows.
Material A - Yield strength min 310 Mpa and Tensile Strength min 450 Mpa-This material may fall in Group I (Grouping is just approximation)
Material B - Yield strength min 350 and and Tensile Strength min 490 Mpa -This material may fall in Group II (Grouping is just approximation)

At the moment, stock of material A is not available with us. Can i qualify the procedure with' Material B' ? I am going to prepare test coupon with butt weld having base metal as' Material B'. Test coupon will not have base metal 'Material A' .

Question is
1) If the process gets qualified with 'Material B', then, can it be used to perform production weld between' Material A' and 'Material B'. My logic is, if procedure gets qualified for higher strength of material then it will definitely work for lower strength of material.
'Material B' is having higher strength than 'Material A'.
2) Does AWS D 1.1 allows it.

Regards,
Santosh

By SCOTTN

Date 03-25-2015 13:49

What are the ASTM spec designations for Material A and Material B?

By welderbrent (*****)

Date 03-25-2015 14:37

Santosh,

WELCOME TO THE AWS WELDING FORUM!!

So, for my non- metric mind, we are dealing with yields between 45k - 55k and tensile of 65k - 75k, very approximate. Thus, it is not because of the limitations on strength of steel that they are not pre-qualified to D1.1.

As Scott asked, could you give us the actual ASTM designations? And, you may be able to determine your groupings for the PQR from B2.1. Have you checked into that yet?

He Is In Control, Have a Great Day, Brent

By 803056

Date 03-25-2015 17:51

If the material is not included (listed) by D1.1, it can still be used if it is qualified in accordance with Clause 4 and when approved by the Owner's Engineer.

Material A must be welded to Material A. Material B must be welded to Material B, and if the materials are mixed, Material A must be welded to Material B.

I would qualify each combination using the fillet test that only requires the coupon pass visual and macroetched. Using the parameters established while qualifying the fillet welds, qualify the combinations using grooved plates (or pipe) to demonstrate the mechanical properties can be met.

Best regards - Al