Home / Standards / GB/T 31049-2014 GB/T 31049-2014 Abolished Top drive drilling equipment for oil drilling rigs 石油钻机顶部驱动钻井装置 Standard Type GBT ICS 75.180.10 CCS E92 Status 废止 Issue Date 2014-12-22 Implementation 2015-10-01 Responsible Dept 国家标准委 Drafting Unit N/A