ASME IX, QW-403.6 3

[0707]

For a SMAW process according ASME IX, QW-403.6, a WPS qualified with a test coupon of 7.5mm thickness qualifies 15mm thickness? Between thickness of 6 and 15mm how should we interpret QW-403.6?

Thanks in advance

Luis Marques

 

[Carburize]

Between 6 and 15 mm the minimum thickness qualified is the actual thickness of the test coupon.

 

[metengr]

QW-403.6 refers to weld coupons qualified with impact testing - see QW-253. Have you qualified for impact testing?

 

[0707]

According QW-253 a change in qualified thickness is an essential variable. According QW-403.6 the minimum base metal thickness is T of the test coupon or 16mm. For T less than 6mm the minimum test thickness qualified is T/2.
Bellow 16mm down to 6mm the minimum qualified thickness is also T/2? In other words A WQR with a qualified test coupon of 7.5mm can be used to weld all the thickness from 7.5mm up to 15mm?

Thank you for the empathy

Luis Marques

 

[metengr]

I must be missing something - are you qualifying this procedure for impact testing?

If yes, QW-403.6 is treated as an essential variable, and as such, the minimum thickness qualified for impact testing is T (coupon thickness) or 5/8", whichever is less. If the thickness of the weld coupon is less than 1/4", the minimum thickness qualified is 1/2 of T. The limitation does not apply if PWHT results in a re-heat treatment of the base material.

If No - QW-403.6 does NOT apply.

 

[stanweld]

Since QW-403.6 only applies for impact test qualifications, and if the design Code requires requires impact testing and qualification per ASME IX, you are correct. Impact test qualification on the 7.5 mm thick coupon qualifies you to weld from 7.5 mm to 15 mm for production materials requiring impact testing per the design Code. Qualification on 6 mm thick coupons qualifies a thickness range between 3 mm and 12 mm.

 

[pandithan]

Agree with Stanweld (material)