exceed to range of WPS???

[duongwe]

dear all,
i have approved WPS for groove of Carbon Steel comply with ASME IX code ( max. 11mm thickness). so now can i weld with double bevel with 18 mm of thickness? because of with single bevel joint i can weld two side and with each side i have imagined as single bevel of 9mm thickness. (mid of 18mm is 9mm). please correct my thinking

 

[stanweld]

No. You will need to qualify a new procedure on material at least 9 mm thick to permit welding 18 mm thick material. Joint design is a non essential variable while base metal thickness is an essential variable.

 

[Duwe6]

Also, think about using a 38mm [1.5"] thick coupon. This will give you an Unlimited Thickness procedure. The extra time and cost of the additional thickness will be fairly small. And it is a capital expense; PQR's last longer than the building your company is headquartered in. PQR's and WPS's last forever.

 

[bhollands]

Dewe6 is correct about using a 1.5" weld test coupon, unless the material is impact tested. In that case you can run into a problem with the minimum base metal thickness. You would be restricted to 16mm minimum.

Bob