Home / Standards / GB/T 13344-2019 GB/T 13344-2019 Active Down-the-hole hammers and bits 潜孔冲击器和潜孔钻头 Standard Type GBT ICS 73.100.10 CCS D92 Status 现行 Issue Date 2019-08-30 Implementation 2020-03-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A