Can you bend a stud back from 30 deg to something less like 15 deg. 1

[fabengr]

I am on a project where the contractor has changed the requirement for bending a stud from the 30 deg that is in the D1.1 to holding us to only bend the stud to 15 deg to satisfy the Clause 7.6. We had several studs that are bend at 30 deg and are being told to bend them back to 15 deg. I am not sure that the D1.1 allows you to bend a stud back. The only Clause that I can find that comes close to addressing this is Clause 7.8.3 titled "Bent Stud Acceptance Criteria."
The question is can or can you not bend a stud back from the 30 deg to 15 deg.

 

[gtaw]

AWS D1.1 Clause 7 addresses the requirements for stud welding. Clause 7.6 states studs welded in the shop or field are prequalified provided the manufacturer performed the qualification tests specified in clause 7.9 provided they are welded to a surface classified as being in the flat position. The maximum angle of inclination is 15 degrees. That refers to the surface on which the studs are welded.


If the welding of the stud is not prequalified, testing per clause 7.6.3 is required. The 30 degree angle referenced be clause 7.6.6.1 is the angle of the stud after being bent.

Clause 7.7 Production Control does include requirements (clause 7.7.1.4)for bend testing the first two studs to an angle of 30 degrees before starting production welding for the shift.

Clause 7.8.1 addresses the bend testing of studs that do not display evidence of flash around the entire circumference of the stud. Should a stud not exhibit the required flash or if it has been repaired, the stud is bent 15 degrees.

Clause 7.8.3 states studs bent during the course of ensuring the production welds meet the requirements of the code may be left in the bent condition. Only if specified by the contract (project specifications, etc.) do the studs have to be straightened.



Best regards - Al

 

[fabengr]

Thank you for this information.
I have two additional questions.
First, I understand that the stud needs to be bent to 30 deg to be qualified. If the customer limits us to only bending to 15 deg (as directed in the project spec) is the stud qualified? My concern is that we have not put enough demand on the weld if we are limited to the 15 deg bend. They do allow us to bend the test (pre-production) stud to 30 deg but they do not want any stud in a final part to have a bend of more that 15 deg (plus 5 deg as a tolerance).
Second, if we have studs on production parts that are bent to 30 deg and the customer requires us to bend them back to the 15 deg spec requirement, are we violating any other AWS requirements?
Is there any information in AWS C5.4 that will provide me with a better understanding of my problem?
Thanks again for your help.

 

[gtaw]

These questions should be directed to the Owner's Engineer (as defined in AWS D1.1). The contractor has no authority to counter what is required by the code. Only the Engineer (the Owner's representative) has the authority to modify the requirements of the structural welding code. Refer to clause 1.4.1.

AWS' C documents are recommended practices and are only to be used as guidance. The recommended practices published by AWS do not override the code requirements.

Are these studs welded directly to the structural member or are they welded through metal decking. If the latter is the case, there re additional requirements imposed.

Best regards - Al

 

[dik]

The Contractor should raise the question if he is knowledgeable, and in this case since he is, the question should be resolved by owner's engineer. The Contractor's responsibility is to construct in accordance with the Specs. If the contractor were not informed, then he is correct to construct in accordance with the specs. He is not normally responsible for knowledge of the design codes.

Dik

 

[Mr168]

Straightening is permitted, but must be done without heating.

That said, I don't understand where 7.6 is coming into play, as that is relative to procedure qualification, and those bent studs are tested to failure when the alternating 30 degree option is invoked. You cannot just bend 10 studs to either 30 degrees or 15 degrees and consider your application qualified per 7.6 (not counting prequalified applications, which are only subject to pre-production testing per 7.7. This is why 10 stud qualifiers are not performed on a production part - they are done on a piece of test material.

Unless there are interference issues, I also have no idea why they would want you to bend previously bent studs back to a lesser degree of bend.