Home / Standards / GB/T 31397-2015 GB/T 31397-2015 Active Heavy duty deephole drilling and boring machines—Specifications 重型深孔钻镗床 技术条件 Standard Type GBT ICS 25.080.20 CCS J54 Status 现行 Issue Date 2015-05-15 Implementation 2015-09-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A