1,Material:Carbon Steel 2,Standard:ASME, DIN, BS, JIS, JB, GB, 3,Cert:TUV ... Certificate,OHSAS18001 Occupational Health & Safety Mangement System Certificate, acquired the license for manufacturing special pressure Pipline equipments from AQSIQ , passed ... and China National Petroleum Corporation.We are also qualified the standard material supplier of China National Offshore Oil Corporation and ...