... mm 4.Place of origin:China 5.Certificate:API.ISO9001:2000.BV structure seamless pipeHebei shengtian (group) seamless steel pipe Co,. LtdWe manufacture ... ,16Mn, 10# 20#,45# S235JR, S355JR;ASTMA252 Gr.2,Gr.3; ST37,ST42,ST52;Gr.B,X42,X46,X52,X56,X60,X65,X70, etc11 ... Africa, Spain, Italy, France, England, the Netherlands,Belgium, etc13.CertificatesAPI 5L; ISO9001:2000