Butt weld fittings

[strumech]

Hi,

Can we weld a 2.5"x1" reducer to a 1"x.5" reducer and then to a 3/4" tubing with butt weld prep at its ends.

All the reducers are ASME B16.9 butt weld fittings.
Any advise is much appreciated.

 

[racookpe1978]

Draw your configuration ((to scale! and with exact proposed part geometries and weld prep's)) and upload the sketch/"print to pdf" file.

I "think" I understand what you "think" you want to do/are planning on doing, but I'm not saying anything until I actually understand your situation.

 

[moltenmetal]

The preparation you've suggesting will probably not pass a radiograph unless you do the correct end prep on the 0.5" NPS pipe end that you intend to butt-weld to the 3/4" tubing. But if you match the tube OD and ID on the 0.5" butt welding end, I don't see a problem with what you're proposing to do.

I wouldn't join tubing to pipe in this way unless there was a good reason not to have a tube fitting there. Instead I'd butt- or socket-weld a tube fitting to the pipe, but that's just my preference.

 

[rcchap]

I agree with moltenmetal. Use a tube fitting.

I work in the nuclear industry, and we will typically use socket weld fittings on pipe that is 2" and smaller, and we almost always use Swagelok tube fittings.

If I were doing the design, I would cap the 2-1/2" pipe with a buttweld cap, and then use a 3/4" sockolet. The sockolet could be on the side of the pipe as a branch connection, or you could attach it to the end of the pipe on the cap. Then use a Swagelok adapter (part number -1210-1-12W) that has a male 3/4" pipe end (to be socket welded into the sockolet) and a 3/4" tubing compression connection.