DOES SS316L P 8.1 WPS/PQR QUALIFY FOR SS304

[AarnoudO]

Hi there,

We are manufacturing a sample cylinder made from SS304.

Normally all our welding is SS316(L).
We therefore have approved WPS/PQR for the welds needed for this product in SS316(L).

Both SS316(L) and SS304 are P8.1 accroding to ASME IX.

Can I have my SS304 welds made by our compannies welders and use the WPS/PQR with SS316(L)?
Are weldments made then approved according to ASME IX / ASME IIIV Div 1.?

Any light on this issue would be highly appreciated.

Thanks in advance,

Aarnoud

 

[2minto]

If you have a WPS and a PQR for P8.1 to P8.1 you can weld any P8.1 material to any other P8.1 material as long as your WPS allows, (i.e. may be limited by thickness)

I checked ASME II part D it has P8.1 materials available in both 316 and 304.

You may have a WPS and a PQR but you also nee to have a welder qualifeid to the WPS which you should have if you are using it for 316L material.

Once you have a WPS and it has a PQR and its approved by Authorized Inspector you are basically done with ASME IX.

If you are welding to a ASME VIII design your weld acceptance criteria will be identified there.

When joining different materials you need to ensure that the different thermal expansions and yield/allowable stresses are covered in the design the WPS/PQR may not be good for all designs.