WPS/PQR for joint design

[andyweld]

For TIG welding, according to Section IX, joint preparation is not an essential variable. But if the weld root open is much larger than in WPS or the bevel angle changed, do you need to prepare another WPS and using the same PQR?
Thanks

Andyweld

 

[metengr]

andyweld;
Using Section IX, QW-256, the above variables you mentioned are considered nonessential, meaning changes can be made without requalification.

 

[andyweld]

Thanks for the reply. Requalification is not required, but do I need to prepare anothor WPS which covers the changed root open? or use the same WPS?

Thanks

Andyweld

 

[Mr168]

I would prepare a revised WPS to permit the alternative joint preparation if it's a repeating occurrence, or at least document it as a one time exception if it's an isolated incident.

While something may be permissible by code, welding beyond the limitations imposed by your procedures violates both the procedure and (more than likely) your quality control program.

 

[stanweld]

Nonessential variables must be addressed in the WPS.

 

[andyweld]

Normally what is the best way to do this? Increase the range of the root open on the WPS and makes it much larger range than PQR or make a new WPS with some weld parameter development for that?

Thanks

Andyweld

 

[Mr168]

How much larger is this new root opening? You have to take into consideration whether the opening is physically possible to weld. Then factor in whether the parameters needed to weld that root opening fall outside those on your WPS. This will dictate the necessary level of revision.

 

[metengr]

You can revise the current WPS to reflect a larger root opeing and included weld angle. Developing a new WPS just adds unnecessary paperwork to the weld program.