1.25Cr-0.5Mo Pipe was designed and fabricated per ASME B31.3. The design temperature is above 455 DegC. Based on ASME Code, Carbon steel can be used below 427 DegC for pressure components. Can I use Carbon Steel structure steel member for the pipe support?
sw007;
Based on my Power Plant experience if the structural member is actually touching the pipe OD surface like a trapeze support or saddle, I would say use a Cr-Mo material. The hanger rods supporting the member can be carbon steel because they would be un-insulated and would be well below 455 deg C.