welded steel pipe Grade: 304.321.316L.309S.310S O. ... ,thermostats ect welded steel pipe Features: 1) Production Standard :ASTM A269;ASTM A554,2) Material of commonly used stainless steel:TP304,TP321, ... TP316L,TP309S,TP310;Material of other stainless steel:202,302,INCOL800,840,8253 ... ,middle,low.8),cuting without burr. Capillary welded steel pipe