Hello Bert, I believe that D1.1 may not make that sort of distinction or allowance. What hogan mentioned referencing seismic requirements and I mentioned about mixing processes, are also possibly different issues. The seismic issue is often imposed upon structures that are within specific geographical areas and based upon sound construction practices for buildings in these seismically affected areas. They spell out additional requirements for welding filler metals and limit use and application of them. These requirements would be based on D1.1 and likely include some of the FEMA specifications that can be imposed as an additional requirement, but are not code or part of D1.1 directly. The mixing of process or fillers that I mentioned are based on some of the metallurgical issues that can arise from using multiple processes or fillers that might not be compatible with one another, thus you would likely want to verify this compatibility either through testing or existing verifiable information on the specific combinations or processes. I am sorry if this seems rather confusing, there are others on the forum here who might be able to condense and clarify this better for you. The information that hogan and I have included is likely not directly related to your original question, yet I do believe that it is something to consider since you have not detailed the application of this process or processes. Best regards, aevald
D1.1 does not prohibit the practice of listing two practices on a single WPS, either prequalified or qualified. In fact, if you look at form N-1 in Annex N of D1.1 it clearly indicates that more than one process may be listed and it provides suitable space to record the essential variables of multiple processes. Note that Annex N is not mandatory, i.e. it is not mandatory to use this form - you can develop your own form to better suit your needs.
Mankenberg