Home / Standards / GB/T 12773-2021 GB/T 12773-2021 Active Valve steel and superalloy bars for internal combustion engines 内燃机气阀用钢及合金棒材 Standard Type GBT ICS 77.140.60 CCS CCSH44 Status 现行 Issue Date 2021-05-21 Implementation 2021-12-01 Responsible Dept 中国钢铁工业协会 Drafting Unit N/A