Welding stainless to carbon steel

[dlkg]

Is it allowable to weld stainless steel to carbon steel using AWS D1.1? I have a WPS for AWS D1.1 that welds carbon to stainless steel using AWS D1.1. Is this allowed by the code AWS D1.1?

 

[metengr]

No, you cannot use AWS D1.1 for DMW. I reviewed an older version of AWS D1.1. The structural welding code does provide a list of approved base metals which are carbon and low alloy steels (section 1.2 Base Metal). There is no mention or reference to stainless steel base material.

You need to obtain AWS D 1.6 Structural Welding Code - Stainless steel

 

[HgTX]

Not that D1.6 addresses welding to carbon steel.

Hg

 

[SJones]

Clause 1.2 item (4) of AWS D1.1 states "Whenever
contract documents specify AWS D1.1 for welding
stainless steel, the requirements of AWS D1.6 should apply."

Don't forget that the D1.1 series of standards are for welding not the application of materials. I also love it when US standards bring in the "Responsible Engineer" who can do what he, or she, likes providing that they stand liable for it. D1.1 also, therefore, states that "the Responsible Engineer is encouraged to use other standards when welding..... stainless steel (D1.6)..". In short, there's nothing really stopping one from applying D1.1 or D1.6 to a dissimilar metal weld.

Steve Jones
Petroleum Development Oman LLC
Muscat
Sultanate Of Oman