SA-672 (electric-fusion-welded steel pipe for high pressure service at moderate temperatures) is headed by a note which requires application under the rules of Section III.
Does it mean SA672 cannot be used for conventional coal fired power boilers?
SA-672 is listed in Appendix A of ASME B31.1 up to 800 °F.

H. Lorenz

Lorenz,

You cannot use SA-672 in Boiler Proper under Section I because it is not permitted in Section I construction, see Section II Part D, Table 1A.
You also cannot use this pipe for boiler external piping, see note 1 of Table A-1 in Mandatory Appendix A of B31.1. Note 1 is applicable for SA-672, if you see the third coulmn of Table A-1 of B31.1.

Hope it helps a little.

_________________
Thanks & Regards,
Nasir
Welding Engineer
DESCON Engineering Limited.
Lahore, Pakistan.
Mobile # 0092-336-4145402