Home / Standards / GB/T 21471-2008 GB/T 21471-2008 Active Machining allowances and tolerances for steel open die forgings on hammer - Shafts 锤上钢质自由锻件机械加工余量与公差 轴类 Standard Type GBT ICS 77.140.85 CCS J32 Status 现行 Issue Date 2008-02-28 Implementation 2008-08-01 Responsible Dept 国家标准委 Drafting Unit 国家标准委