alloy steel, ASTM A213, ASTM A213 T12 Seamless alloy tube, ASTM A213 T12, heat exchanger tubes, steel tube, steel tubes, superheater tubes
ASTM A213 T12 containing the letter H in their designation have requirements different from those of similar grades not containing the letter H.
These different requirements provide higher creep-rupture strength than normally achievable in similar grades without these different requirements. ASTM A213 T12 tubes shall be made by the seamless process and shall be either hot finished or cold finished, as specified. Grade TP347HFG shall be cold finished. Heat treatment shall be done separately and in addition to heating for hot forming. The ferritic alloy and ferritic stainless steels shall be reheated. On the other hand, austenitic stainless steel tubes shall be furnished in the heat-treated condition. Alternatively, immediately after hot forming, while the temperature of the tubes is not less than the minimum solution temperature, tubes may be indivi