PQR essential: Groove angle and type

[nkvon]

Dear Experts,
I have confused when prepared WPS follow AWS D1.1
I qualify CJP groove bevel angle is 47 degree, Could it qualified for 60 groove weld degree or not, I not clear in" except qualification of any CJP groove weld qualifies for any groove detail conforming with the requirements of 3.12, 3.13"

table 4.5 state that:
31) A change in groove type (e.g., single-V
to double-V), except qualification of any CJP groove weld qualifies for any groove detail conforming with the requirements of 3.12, 3.13
33) A change exceeding the tolerances of 3.12, 3.13, 5.21.4.1, or 9.10, 9.11, 9.11.2, and
9.24.2.1 involving:
a) A decrease in the groove angle
b) A decrease in the root opening
c) An increase in the root face

Thanks all

 

[Mr168]

The CJP groove weld qualifies for all of the CJP prequalified joint details correlating to the process qualified. If you are outside the limits of the prequalified joint details, then you are limited by the requirements and tolerances of variables 31 and 33.

Short answer - yes, a groove weld qualified at 47 degrees can be used to weld at 60 degrees. The opposite (qualify at 60, weld at 47) would violate variable 33 and not be permitted.

 

[nkvon]

Thanks for your respond Mr168,
It rather clear but I have 1 case cause little confuse to make clear: example if I qualify 60, so it shall qualify all joint in CJP prequalified at fig 3.3 and It will cover join single bevel 47 degree (B-U4b-GF), because it in tolerance(-5, +10) but it sound like violate with variable 33,
May I could use WPS 60 degree to apply this case?

 

[Mr168]

The prequalified joint details stand alone, and then the qualified joint details stand alone. Variable 33 places a limitation only on a decrease in groove angle.

So, ignoring the prequalified joint details, you qualified a single bevel at 47°. Therefore, you have qualified a single bevel with a minimum groove angle of 47°, and no limit on the maximum groove angle provided it meets any detail drawing tolerances.

If you qualify a single bevel at 60°, you get any joint detail of Figure 3.3 by virtue of Variable 31. Therefore, you also get a 47° single bevel per detail B-U4b-GF. If you tried to weld a 30° single bevel with this qualification, you would not be qualified because you do not meet the conditions of variables 31 (you do not meet the limits of the prequalified joint detail) or 33 (you are not qualified for a decrease in groove angle for joint geometries other than those specified in Figure 3.3).