... boiler Seamless steel tubes for low and medium pressure seamless carbon steel tubepetroleum casing tube ,petroleum cracking tube, seamless steel tube ,seamless steel pipe,ASTM ... ,seamless steel tube,seamless tube,seamless carbon steel tube, product informationMETERIAL:ASTM A106. GRB ... ASTM, JIS, DIN, GB , and so on.Material: Q235, ST52,ST42,A106 -a, A106-B , and so on Boiler seamless carbon steel tube ...