ASME IX weld qualification scaling
ASME IX weld qualification scaling
(OP)
Hi could you please let me know where can i find information in the ASME IX for the scaling thickness of the pipe for qualifying butt welding.
i have two different size pipes with two different thickness. So can I use the minimum thickness pipe to qualify for both butt welding or do I have to qualified separately.
i have two different size pipes with two different thickness. So can I use the minimum thickness pipe to qualify for both butt welding or do I have to qualified separately.





RE: ASME IX weld qualification scaling
This qualifies Diameters from Ø 0.84" and Larger, provided the material thickness of the larger pipe is equal to the tickness range qualified of 2T. For example: SCH 160 is .188" x 2 = .375" thickness qualified or XX Hvy is .294" x 2 = .588" thickness qualified.
For direction, refer to ASME Section 9:
- QW-450/QW-451.1
- QW-452.1(a)
- QW-452.1(b)
- QW-452.3
- QW-461.9
RE: ASME IX weld qualification scaling
The only problem with using 1/2" is you require multiple coupons.
This route is only usually used if qualification is required for welding 1/2" in production.
A 2" coupon will give almost the same diameter range, is easier for the welder and only requires 1 coupon.
A 1/2" coupon qualifies for size welded to unlimited.
A 2" coupon qualifies for 1" OD (25.4 mm)to unlimited. A 3/4" pipe has an OD of 26.7 mm so basically it is 3/4" (NB) to unlimited.
Regards,
DD
RE: ASME IX weld qualification scaling
I appreciate the input, it's nice to learn about how others handle Procedure and performance qualifications.
I'm not entirely sure if a Ø 1/2" coupon would require multiple coupons...
The lab we deal with is able to extract two root and two face bends from a single Ø 1/2" SCH 160 coupon to qualify 6G position according to QW-463.2(d).
What I typically do, is qualify the procedure (depending on the application) using a 3/8" plate [1/16" to 3/4" thk], single sided butt-weld in a 1G or 2G position. Then I qualify the welder using a 1/2" SCH 160 pipe in 6G position to cover the techniques and processes we require.
Since we are required to weld small bore piping, using 1/2" SCH 160 pipe works out best for us as you explained.
Thanks,
Don
RE: ASME IX weld qualification scaling
My apologies.
Based in the Southern Hemisphere for some reason nobody uses the mechanical option for welder qualification.
It is always volumetric (predominantly RT with UT coming into play now)
Regards,
DD