Home / Standards / JB/T 4720-1992 JB/T 4720-1992 Abolished 管壳式换热器用非金属垫片 Standard Type JB ICS N/A CCS N/A Status Abolished Issue Date 1992-05-07 Implementation 1992-10-01 Centralized Committee 机械工业部 Issuing Authority 机械工业部