This standard specifies the basic requirements for the type of circular die frame, interchangeable dimensions and markings. This standard applies to circular die frames for hand use.
GB/T 970.3-1994 history
2008GB/T 970.1-2008 Circular screwing dies.Part 1:The types and dimensions for circular screwing dies and die stocks
1994GB/T 970.3-1994 Die stocks--interchangeability dimensions
GB/T 970.3-1994 Die stocks--interchangeability dimensions was changed to GB/T 970.1-2008 Circular screwing dies.Part 1:The types and dimensions for circular screwing dies and die stocks.