Welding non-critical non pressure retaining components

[ME231]

Hi All,
I have worked with PQR's and WPQ's for some ASME welds. What is the requirement for non-pressure retaining, non-critical welds - I am talking about mostly structural welds used to join non critical components together. Quite obviously, codes exist for the important stuff, but I cant seem to find guidance for any of the non-critical stuff (eg. welding a wire mesh to a ring that needs to be placed inside a pressure vessel to act as a filter)
Is a proper WPS/PQR/WPQ even required?
Thanks much!

 

[gtaw]

If the weld is to a part of the vessel, in the vessel, or to a vessel it falls under the applicable pressure vessel code.

If a leg is welded to a pad welded to the vessel pressure boundary, the reinforcing pad to the pressure retaining wall is a "code" weld. A leg welded to the reinforcement pad (not welded to the pressure retaining boundary) can be considered as being separate from the pressure vessel code.

In my opinion there is no such thing as a non-critical weld when dealing with a bomb, which is exactly what every pressure containing vessel is, a potential bomb.

Best regards - Al

 

[ME231]

i understand your point gtaw. but the weld i am talking about, or atleast, the welded part is only going to be placed inside a pressure vessel, not attached to it. your thoughts about that?

 

[gtaw]

The second paragraph provides an example of what would be a code required weld and one that is not.

I think it is silly to use an unqualified welder for any weld.

It is no different from calling a draughtsman an engineer. While the draughtsman may have plenty of experience with number crunching under the tutelage of an engineer, he is not a engineer until he has passed the P.E. examinations. A welder that has not passed the performance tests to demonstrate the ability to deposit a sound weld is only a "wannabe welder" in my opinion.

Not every welder has to pass a pipe test consisting of an open root groove weld in the 6G position. There are many different tests that can be administered to allow the welder to demonstrate his skill. The goal is to select the test that is appropriate for the production position, using the appropriate welding process, proper filler metal, and product form to demonstrate he possesses the skills needed to produce an acceptable production weld. There is no justifiable excuse to use an unqualified welder for work that will be sold to a customer.

If this is a garage project that will only endanger the person doing the work, then go for it. Should something fail and if the only person placed in harms way is the person that welded it, it is proof that Darwin was correct and it is one of many ways the gene pool is enhanced by eliminating the undesirable genes.


Best regards - Al