Welding End Caps to Reducing Tee 1

[pipeneer]

Hi
since I'm not well versed in Welding, my question is Can one weld 24" end caps to run of the 24"x10" Red.tee (Hydrostatic testing)Mat. A234-WPB and cut them away after testing without damaging the bevels on the Tee ? so it could be welded again in the 24" header? As it was mentioned, can I use pup pieces and then Cap them and after test cut the caps but leave the pups and weld the Tee with the pups in the main 24" line after cutting back the Pup pieces to fit?
Thanks in advance

 

[unclesyd]

You can do it either way, size on size, as I understand the OP. Cutting out a weld and rewelding is no different that making a repair during fabrication. When you reweld the line make sure you check the bevel, We use PT.
On our 24" steam lines we will target the line and then weld on cap for the hydro. We have a lot tees in our system where the run was caped for future expansion. I have used pup pieces but I can't recall leaving one installed.
Also I have used a pup piece with a reducer and smaller flange to failitate hydrotesting.

When you are doing this use the same weld procedures as the piping code calls for.

 

[Mr168]

In my experiences, you'll have less of a problem with weld end prep damage with a cap, and more of a "he just gouged the living daylights out of my fitting" problem, as welders and fitters have a tendency to get a little carried away with gouging rods and whiz wheels.

Thankfully, most of those bigger fittings have plenty of meat in them to stay above min wall when it happens, and the situation can typically be rectified with some grinding and weld build-up.

 

[racookpe1978]

It will be better to weld out the piping to the runs to the flange points (where your valve will be) and then cap off the test rig at the permanent flanges.

What's your hydro pressure" There are bolt-on temporary fittings that might work for a shop hydro.

 

[11echo]

SO don't you have to hydro-test again when you cut the cap off and re-weld? I'd suggest using flanges with blinds on them. You can hydro-test everything once and "IF" you need to connect some other line or equipment down the line is just a bolt-up connection.

 

[pipeneer]

Thank you all for the suggestions, but since I do not have any flanges in the 24" run of the line, can not go with welding 2 new 24" flanges and blind them for the test, so I guess I just weld the Caps on the Tee, Cross my fingers!!! and after the Hydrotest and cutting away the Caps, weld the whole spool includung the Tee into the line with some touch up on the bevells of the Tee.

 

[unclesyd]

Talk to your Authorized Inspector about a "Golden Weld". All that is normally required is that the weld be checked RT.
flanges are bad news in 24" steam lines. The only flanges we have in our 24" steam lines are at the PRV and RV.