welded stainless steel pipe Material Grade: 304,304L,309,310S,316L,321,TP317,TP347 ... : Zhejiang, Jiangsu, Shandong of China (Mainland)* Mill: Qingshan, Baofeng, Taigang pipe* Certification: ISO* Material Grade: 304,304L,309,310S,316L,321 ... the Pluralism welding system, Heat treatment, Eddy current test on line, Hydraulic test, Mechanical and Technical performance test, Crystal erosion and ...