Groove change and groove angle change

By StaceyD Date 08-19-2009 23:25

The contractor changed the groove they had a qualified/approved WPS for, from a Double V butt joint (welded by OD and ID SAW) to a Double bevel butt joint. I am told that this change in grooves does not require re-qualification per D1.1 because a double bevel butt joint can be found among the Pre-qualified joints in Section 3 for CJP welds. However, the groove angle went from 60 degrees down to 30 degrees. This I am now told is the reason that a new PQR must be run. What was explained to me was that in the diagram for the double V, the SAW tolerance for decrease in groove angle is -5 degrees. What confuses me is that I see no direction in D1.1 that tells me I should go to the diagram for the joint that was instead of the joint that is. 1) Is the interpretation that was provided to me true? 2) What in D1.1 tells me which pre-qualified joint to look to for the tolerance in the groove angle?

Responses appreciated.

Thanks!

By Lawrence (*****)

Date 08-19-2009 23:39

First off you say, "qualified/approved"

There can be a big difference between qualified and approved procedures.

If you requre qualified procedures than you are limited to the tollerances in the PQR period... If you go beyond them you must qualify a new procedure per section 4 to be in compliance.

If you mean you have a prequalified procedure that has been approved by your engineering authority this may be another matter entirely. You may possibly then be able to select another prequalified joint for your SAW operations and simply generate another prequalified WPS for production, so long as you are compliant to your contract and the rest of section 3 of D1.1.

By StaceyD Date 08-20-2009 16:15

Thank you for the reply. My questions were not answered though.

By js55

Date 08-20-2009 12:59

A double bevel TC-U5-S allows only a 55deg min bevel as fit.

By StaceyD Date 08-20-2009 16:20 Edited 08-20-2009 16:24

Thank you. The question remains...what in D1.1 tells me to go to the original groove configuration or to the new groove configuration? In which pre-qualified joint configuration do I find my tolerance? I understand that TC-U5-S has tolerance of -5 degrees. What tells me to look there?

By js55

Date 08-20-2009 17:40

If I understand the question, nothing 'tells' you to look there. You decide based upon the bevel configuration you intend to use. If there is one prequaled you go there, for example TC-U5-S. If there isn't a prequal then you have to qualify one.

By hogan

Date 09-16-2009 08:27

StaceyD,
Maybe it's just me but I think "the question is not anwsired...." & "the question will remain...."
It seems clear to me that your lacking the ability to ask your question in a way that the forum can respond to.

By motgar

Date 08-20-2009 16:34

StaceyD,

Let me see if I have this right. The original WPS was qualified and has a supporting PQR. The original WPS was approved for production. The original WPS utilized a 60 degree double V groove weld. It may appear similar to joint designation B-U3c-S, in Section 3 of the D1.1.

Assuming you have a qualified procedure as per Section 4, then Table 4.5.31 states: A change in goove type (e.g., sigle-V to double-V), except qualification of any CJP groove weld qualifies for any groove detail conforming with the requirements of 3.12 or 3.13. Assuming that your qualified procedure is a CJP.

Since the original joint design, double V, was qualified then changing it to a double bevel is allowed. Provided it meets the requirements of 3.12 or 3.13. In other words, a change in joint design is allowed as long as it is to a pre qualifed one. However there is no joint designation for the 30 degree double bevel SAW joint. Therefore a qualification will need to done per Section 4 for the new WPS.

As for you second question. See also Section 3.12 and 3.13 for pre qualified joint tolerances. From there it will direct you to figures 3.3 and 3.4. Main difference between them are; figure 3.3 are all PJP while 3.4 is CJP with some limitations. Usually in base metal thisckness. + 10, - 5 degrees angle tolerances seems to be the norm.

Hope that helps.