Welding 321 SS tubing to P22 Sch 40 Pipe

[tdowd151]

I am looking for some information on WPS requirements for welding 321 Stainless to P22 pipe. The information is below:

Process conditions

Plant life: 30 years
Temperature cycles once every day, constant pressure
Max temp: 750 deg F
Min temp: 180 deg F
Pressure: 230 psi

Materials

Pipe spool: P22 schedule 40 piping with a beveled end, beveled down to .079" thickness
Tubing: 321 SS, 2.5" diameter, square land, .087" thick
Pipe: Carbon Steel schedule 40 piping with a beveled end, beveled down to a .079" thickness

I need procedures to weld:

-Pipe spool to tubing
-Tubing to tubing
-Tubing to Pipe


With this information can anyone tell me what is needed. I would like to do a bi metal PQR if at all possible to keep the costs down.

Any info would help.

T. Dowd
CWI
NDT Level II - MT, PT, UT, RT, VT
ICC Certified
Nuclear Leaad Auditor Trained

 

[stanweld]

Recommend welding filler metal to be ERNiCr-3 or similar. Preheat @ 300 F.

 

[Duwe6]

You might look at ER309L, to save a little money over ERNiCr-3. And it welds 'easier'.

 

[stanweld]

Dewe6,
The daily temperature cycles would limit the thermal fatigue life using ER309L vs a Nickel base filler.

 

[ione]

Well spotted stanweld. We've had good results with Inconel 625

http://www.specialmetalswelding.com/products/datash/fm625.pdf

 

[gtaw]

What welding code or standard are you welding to?

The CWI credential alone does not qualify an individual to develop a WPS. If you are on unfamiliar ground, consult with a professional that is expereinced in developing WPSs and one that is familiar with the materials your are working with.

Your starting point should be a review of the applicable welding standards. In this case I suspect ASME Section IX and either B31.1 or B31.3 would be applicable.

Best regards - Al