Home / Standards / JB/T 7021.2-1993 JB/T 7021.2-1993 Abolished 块式制动器 制动瓦块 Standard Type JB ICS N/A CCS N/A Status Abolished Issue Date 1993-09-21 Implementation 1994-07-01 Centralized Committee 机械工业部 Issuing Authority 机械工业部