Pressure vessel ASME code 1

[Marke525]

I recently came across a problem regarding material used in a pressure vessel. We have always used material specified to ASME SA249. Now I am being asked to supply material to SB691. Does this only apply to AL6XN material or to 316L also?

 

[metengr]

Yes, it applies only to AL-6XN. The Standard Specification of SB-691 applies to only UNS N08367 and N08366. The actual specification is titled "Specification for Iron-Nickel-Chromium-Molybdenum Alloys (UNS N08366 and UNS N08367) Rod and Bar".

 

[bssem]

SA-249/SA-249M Welded Austenitic Steel Boiler, Superheater, Heat Exchanger, and Condenser Tubes
SB-691 Iron-Nickel-Chromium-Molybdenum Alloys (UNS N08366 and UNS N08367) Rod, Bar, and Wire

Per your question, you are therefore comparing Tubes with Rod/ Bar/ Wires.

The spec. for AL6XN Tubes is ASME SA-249 (spec. common for AL6XN & 316L welded tubes)

The spec. for SS316L Rod, Bar, and Wire is SA 479.