AWS D1.1 T, Y and K Joints

By swnorris (****)

Date 07-31-2007 16:51

Not sure what you're asking. T-K-Y joints are just that. They have a shape of a T, Y, or K. Sounds like your situation is a Y joint. What is the welding requirement of the joint? There are prequalified PJP and CJP joints that have to meet specific criteria in order to be deemed prequalified. For example, an angle of less than 30 degrees is not prequalified.

By Richard V. Roch (**)

Date 07-31-2007 17:16

It is an angle of less than 30 degree. There has been some discussion that the definition for this joint is that it has punching design criteria and that not just because we are using pipe for bracing should it be considered a T, Y or K joint. I guess that what I am being told is that just because it looks like a T, Y or K joint does not necessarily mean that it is per AWS D1.1?
thanks again

By hogan

Date 07-31-2007 17:33

can you elaborate on that?

By swnorris (****)

Date 07-31-2007 18:03

I'd think it would still be a T-K- or Y, it's just not a prequalified T-K- or Y.

By Richard V. Roch (**)

Date 08-01-2007 15:37

I guess the question is, does a T, Y or K joint need to meet a certain design criteria to be considered a T, Y or K joint per AWS D1.1, or is any pipe to pipe bracing on structural considered a T, Y and K joint?
Thanks

By swnorris (****)

Date 08-01-2007 19:13

I think that if the pipe or tube is in the T-K-Y configuration, then it is considered a T-K-Y joint.......Am I missing something here?

By Richard V. Roch (**)

Date 08-02-2007 11:43

I don't know? Again there is a debate going on with eng. about this subject. The thought is that T, Y and K joints are where a branch member is welded to a main member and has punching load applications. This is why I decided to ask for help from all the good folks at this forum.
Thanks

By swnorris (****)

Date 08-02-2007 13:04

That is correct. T-K-Y connections are a generic term that describes tubular connections where branch members are welded to a main member, or chord, at a centering point. All three are subjected to punching loads, but each one reacts differently and has to meet different design criteria.

By Richard V. Roch (**)

Date 08-07-2007 18:50

Thanks, our client just recently came back to us and pretty much said the same thing. No T, Y, or K joints existed on the project even though we had some pipe to pipe joints that resembled T, Y, and K Joints.
Thanks again everyone