... boilers, heat exchangers, super heaters, condensers, and catalytic tubes, refining furnaces etc. 1 General usage pipeProduct Description: ... boilers, heat exchangers, super heaters, condensers, and catalytic tubes, refining furnaces etc. Standards: ASTM/ ASME A213/SA213, ... 321.Surface Type: These tubes can be supplied with BA surface finish or with polished outside surface and inside surface. Outside ...