Cold forging
Cold forging is the most widely used technique for producing screws and bolts from M1 and up to M24.
The process is characterized by cold pressing the fastening elements into a cold-forging machine by adding the material as wire lengths from coils / rolls of steel into the cold forming machine, as in various molds and shaping stages, depending on the design of the mold, the molds are cold-molded.
No heat is added to the steel in the process, but the heat arises through the friction and friction heat of the cold forming process.
The cold forming process is significantly faster and cheaper than heat forming.
Hot forging
Bolts and nuts over the M24 are heat-formed in most cases.
The process is characterized by inductively heating pieces of steel and flanges up to 1150 degrees centigrade. Then the blank is pressed into a mold tool at high pressures between 800 and 1000 tonnes. The steel flows into the mold under high pressure and the desired bolt or nut is formed.
Structure breaking of the steel
Cold forming as well as the thermoforming processes are characterized by not breaking the structure of the steel.
The structure is broken and the mechanical properties are changed if you process the material such as by milling and turning.
