Developing welding procedures should always be done by someone who is properly qualified.  This does not mean you need a degree or many years of experience or a certification from a governing body..  It simply means you have a sound understanding of what is required to make a successful weld. When presented with metals that are unfamiliar, the person in charge of developing procedures must have a process to ensure that an adequate procedure is developed. This involves testing for which most codes and standards provide guidance. 

This week we are starting a series of articles on the most important things to consider and do when developing welding procedures.  Today we provide an excerpt from our guide Welding Procedure Development for Non-Welding Engineers to kick things off.  

Developing a welding procedure is the responsibility of the welding engineer. Most fabricators don’t have a welding engineer on staff and require that those with the most welding knowledge develop the WPS.  Many times this falls in the hands of the certified welding inspector (CWI).  This is not a bad thing, after all, CWIs are trained on interpreting and applying welding codes. However, keep in mind that a CWI may have sufficient knowledge of welding processes and may have experience writing procedures, but a CWI certification does not guarantee this.

A CWI may easily create WPSs for steel structures since the code (i.e. AWS D1.1) provides a lot of guidance.  AWS D1.1 will tell the user what steels are covered under the code, what the matching filler metals are for each of these steels, whether or not preheat is required, special considerations for specific steels such as quenched and tempered steels, and much more.  But what happens if you have a base metal not covered by the code?  What filler metal should you use?  Should you be concerned about excessive heat input and its effects on mechanical properties?  Should you be concerned about corrosion or other problems that cannot be detected through normal inspection?

Developing a WPS for materials that are not covered by a code or that are highly sensitive to cracking or other defects is a serious matter.  Even accomplished welding engineers struggle with this.  Not many welding professionals are able to develop a sound WPS without assistance.  This assistance may come from colleagues, books, the internet, the manufacturer of the base material, the manufacturer of the filler metal or other industry experts. 

What welding engineers that develop WPSs do well is they know what questions to ask. They have a process to follow in order to develop a welding procedure.  They use this process whether they are welding ASTM A36 steel, super duplex stainless steels, cast iron, aluminum, galvanized steel, or any other material. They never make the assumption that the welding procedure that worked on one base metal will work on another.  

Just like a CWI knows how to use welding codes and knows where to find answers, so does a welding engineer when it comes to developing welding procedures.  A problem in our industry is that we have a tremendous shortage of welding professionals.  This includes welders, fitters, cutters, inspectors, technicians, supervisors and welding engineers to name a few.  

This means that the responsibility to develop a welding procedure can land on anyone, regardless of their work experience, schooling or background.  And this can be a daunting task given the implication of writing a welding procedure.  The good news is that with a bit of welding experience, proper instruction and basic knowledge of welding processes anyone can write a welding procedure as long as a proven process is followed.

Over the next few weeks we’ll explore the key areas of developing a welding procedure that anyone, even welding engineers, should follow in order to develop sound welding procedures. 

Reference:

Welding Procedure Development for Non-Welding Engineers