Home / Standards / MT/T 789-1998 MT/T 789-1998 Abolished 煤田钻探金刚石取心钻头 Standard Type MT ICS N/A CCS N/A Status Abolished Issue Date 1998-11-10 Implementation 1999-04-01 Centralized Committee 国家矿山安全监察局 Issuing Authority 国家矿山安全监察局