1.mild carbon steel pipe astm a 106 gr.c 2.ASTM A213,A210-C,A179,A192,DIN17175ST37. ... heater tube2 Production Standard mild carbon steel pipe astm a 106 gr.cASTM SA213, SA335, A369, A209, A250, G3462, G3467, DIN17175 ... seamless steel carbon pipe mild carbon steel pipe astm a 106 gr.c