Welding 17-4 PH material with Low Carbonsteel 1

[bmoorthy]

Hello all

Background:

Supplier is American
Contractor: Non American
User:American
Standdard: API 2C
Item: Crane

We as contractor, are required to review the WPS and PQR and after our review the WPS and PQR are reviewed by the user.

After review there is a process of commenting and approval.
In order to reduce the cycle time, the review of the WPS and PQRs are reviewed simultaneously by the User and the contractor (This is also regularized contractually).

An american supplier had submited a WPS (With Supporting PQR) for welding 17-4 PH material with A 36 material (Load Bearing PIN)

The PQR has been tested to AWS D 1.1 (All tests have been performed (Bend, macro, Tensile, Etc) in full compliance to AWS D 1.1

Only one minor catch: The electrode used in E 6010 followed by E 7018.

The question is: is it permitted to use Carbon steel electrode to weld a high alloy material?

I Know generally one does not use CS electrode while welding CS and High Alloy.

My understanding is 17-4 PH is High Alloy.

The user did not have any objection for the given combination of material and choice of electrode.

I could not even fall back to AWS D 1.1 or API 2C or for that matter ASME Sec II C or any ANSI that gives the choice of electrodes to contractually enforce the usage of High alloy electrodes.

The next question is are there standards that give guidelines for the choice of electrodes?

 

[unclesyd]

Something is wrong here, even though you will be able to weld 17/4 with CS electrodes you will not get any of the chemical and physical properties of the heat treated 17/4 PH material.

Why would one want to weld on a load bearing pin in the first place.

There are more questions than answers for this post.


Checkout the brochures on welding 17/4 PH at this site.

http://www.aksteel.com/markets_products/stainless_precipitation.asp

 

[metengr]

The specific selection of a suitable filler metal is typically not addressed in almost all Codes and Standards. Codes and Standards are not substitutes for sound engineering judgment or relevant experience. Having said this, I agree with unclesyd's comments.

Have you actually reviewed the results of the PQR to determine and verify actual tensile values and bend test results? What is the weld joint configuration - fillet or groove?

As a minimum for this type of dissimilar metal weld joint, you should be using an austenitic filler metal - 3XX or Ni-base.