need clarification

Date 08-25-2012 14:55

I need to qualify a WPS for GMAW (CJP) single bevel groove weld in 2" thick SA-36 materal W/O backing.. joint consists of a 7.5"OD x3/4" wall tube inserted in a 42" OD (formed pipe) with a 2" wall. tube will be flush with 42" OD creating a single bevel groove. Table 4.1 note C refers to Figure 4.25(A) for qualification testing; after testing and upon submittal it was not approved, reason: Table 4.5 Essential variable requiring retesting (Item 31) is a change in groove type. PQR was single V groove, WPS was single bevel groove. Looking for some input... Currently rewelding and testing new coupon with single bevel groove.

By 803056

Date 08-25-2012 18:28

The groove detail in figure 4.25 does not specify a groove angle. It simply suggests a 60 degree included angle.

You failed to provided detailed information with regards to the production groove, but if experience is a guide, I would bet someone specified a 45 degree angle for the single bevel groove. There in lies the problem. From table 4.5 item 33 addresses changes in the groove angle, fitup, etc. It would come as no surprise that a single bevel groove could run afoul of item 33.

Were you to qualify the WPS (as you appearently did), you could use any prequalified groove detail as per item 31.

Best regards -Al

By alumtig (**)

Date 08-27-2012 18:25

Hi Al,

Thanks for the reply, I intended to represent the production weld as a Single bevel groove with a 45 degree included angle. I see upon carefully reviewing figure 4.25(A) that the groove angle "a" references "production groove angle" I did not see that prior to reading your reply. I have rewelded a new coupon, and completed the qualification process, the new WPS has been approved but I needed to understand what I had done incorrectly. I think I have it now. :)

By S. WINAI (**)

Date 08-26-2012 06:31

Table 4.5 sub 31. A change in groove type(e.g..single-V to double-V), except qualified of any CJP groove weld qualified for any groove detail conforming with the requirements of 3.12 or 3.13
WPS not approve cause 3.13.4 Tubular Butt Joint (2) Nonprequalified Joint Detail. There are no prequalified joint details for CJP groove welds in butt joint make from one side with out backing.

if PQR was single V groove with out backing or back gouge u need to requalified PQR single bevel. unless u PQR qulified with backing or back gouging then can use prequalified joint detail in Figure 3.4 any groove type (single bevel,single v or double v)

if im missing some thing pls advise

Thanks

winai