This standard specifies the structural type and size, technical requirements and markings of cold heading GB 70 hexagonal socket head screws M4 ~ M20 hexagonal concave die. This standard applies to the molds of double-mold automatic cold heading machines and multi-station cold heading machines.
JB/T 4212.12-1996 history
2014JB/T 4212.5-2014 Cold heading dies for hexagon socket head cap screws.Part 5: Die pieces
1996JB/T 4212.12-1996 Mold for cold heading interior hexagonal cylindrical head screws Hexagonal female die
JB/T 4212.12-1996 Mold for cold heading interior hexagonal cylindrical head screws Hexagonal female die was changed to JB/T 4212.5-2014 Cold heading dies for hexagon socket head cap screws.Part 5: Die pieces.