Threaded/Screw Fitting for Fuel Gas Service

[ppmsb2008]

Hi,

There is some concern to use threaded/screw fitting for fuel gas line (150 Ib rating) for our newly installed fired heater.

Normally our company standard is to weld.

Any advise?

Thanks

ppm

 

[MikeHalloran]

Well, it's YOUR company standard.

What do you want US to do about it?



You might want to re-read it, and see if it allows threaded pipe below some threshold of size. You didn't give us a clue about that.



Mike Halloran
Pembroke Pines, FL, USA

 

[ppmsb2008]

This threaded joint is for fuel gas skid part of fired heater package equipment. The whole things supplied by the package vendor.

We didn't realize it until it was delivered to site for site erection.

Just checking whether is it common to have threaded connection for below 4" line (150Ib rating) for fuel gas service.

 

[MikeHalloran]

I suppose you could take the position that it's part of a packaged unit, and the detail design of what's inside it should not be your problem, unless it actually becomes a problem. I would probably escalate that decision to a higher pay grade, with appropriate background material.

Some of the specs I've read recently specifically allow threaded pipe in sizes 2" and under for low pressure services like fuel gas. It must be an old paragraph; my shop crew automatically butt welds 2" and up if they possibly can.



Mike Halloran
Pembroke Pines, FL, USA

 

[eadwine]

I take it this is thr'd C.S. pipe. If so, just seal weld it and your done. Just make sure the line isn't operational already, for obvious reasons.