Valve Socket Weld Question

[af09]

Note: Please see pictures below for a visual.

A friend asked me regarding the integrity of a socket weld done on a connection from a drain valve to a tee. Essentially, the drain valve ordered came in threaded on the end that was intended to be welded into the tee. So, he decided to go ahead and weld it as such. The customer came back with concerns about the weld's integrity once informed about the end being threaded prior to it being welded. Does anyone have any insight on how one could go about analyzing the strength of such a weld; whether from a calculation-based or even simulation-based perspective? Or any physical test that can confirm the integrity of the weld? Also, would this be considered in compliance with ASME B16.11?

Any thoughts or recommendations would be greatly appreciated. Thank you.

Pic 1 (parts separated):

https://files.engineering.com/getfi...7e-86b5-b6a8db45c9ea&file=20230727_110052.jpg

Pic 2 (fully inserted):

https://files.engineering.com/getfi...81-3d8e54628362&file=IMG-20230727-WA0004.jpeg

Pic 3 (full inserted close-up):

https://files.engineering.com/getfi...7e-89ef-512e4a80d1b2&file=20230727_110153.jpg

Pic 4 (Welded final result):

https://files.engineering.com/getfi...2a-8285-cc46b8818574&file=20230727_110401.jpg

Pic 5 (Welded final result 2):

https://files.engineering.com/getfi...50-0ead756810c5&file=IMG-20230727-WA0008.jpeg

 

[LittleInch]

Can you use the image function please to load the images?

but I can't see the issue myself. might look a bit odd, but welds , well weld stuff together so the screw bit is not relevant IMHO.

Socket welds are pretty crappy welds anyway being dinky little fillet welds but people seem to like them for small bore stuff so I just let it go.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Krausen]

It appears you basically have a seal-welded threaded connection on this drain valve now. This isn't a big deal, but the thing to realize is the integrity of this joint is really only determined by your thread engagement, with the seal weld only being considered "insurance" for any kind of potential leakage from the threads. The seal weld itself is typically not given any credit for joint integrity, and is therefore not analyzed. So you basically just have a B16.11 threaded joint here & should hydrotest it as your physical test to confirm integrity.

On the subject of socket welds - I'd much rather have a socket weld joint compared to a threaded joint (or threaded & seal-welded) in general on any small bore connection that isn't buttwelded.

 

[LittleInch]

Well look on the bright side here - no one will know!

But ref your other thread - I would leave the threads on and not get the valve too loose in the socket weld hole.

Then next time do it properly....

I don't think this is a seal weld threaded connection as the threads are doing nothing and it's all down to the fillet weld top of the socket weld tee.

I think you essentially have a socket weld joint here and act accordingly.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[af09]

Yeah, my apologies, I didn't explain that the tee internal bore was not threaded. It was intended for a welded connection. He ultimately decided to replace one of the two parts in order to make it a more reliable connection. Thank you guys.

 

[mk3223]

Agreed that this is basically a seal welded which looks like a bridge weld similar to the connection with a short nipple.
Of course, the weld may be tested with required NDE and padded the leak test.