Home / Standards / HG/T 21631-1990 HG/T 21631-1990 钢制有缝对焊管件 钢制有缝对焊管件 Standard Type HGT ICS 71.120 CCS G91 Status N/A Issue Date 1991-02-01 Implementation N/A Responsible Dept 化学工业部 Drafting Unit N/A