Cold heading machines form a metal blank into shaped parts by using a reciprocating ram to force a punch into a preformed die. Heat is not added during part manufacturing.
The cold heading process uses high speed automated "cold-headers" or "part formers." This equipment has the ability of transforming a wire into an intricately shaped part with tight and repetitive tolerances using a tooling progression at speeds up to 400 pieces per minute.
A length of wire is placed into a die, and a hammer then upsets or extrudes the material into various desired forms.
Because the cold heading process is volume specific, and the process uses a given volume to form a finished intricately shaped part of the exact same volume, the material will simply be rearranged. Loss of material, or scrap, is minimal.
In addition to upsetting and extrusion, cold heading is often performed along with other cold forming operations, such as:
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Types of Equipment
The two basic types of equipment used in cold heading are "cold-headers" and "part formers." Both use horizontal reciprocating rams and stationary bolsters. Stalcop uses equipment from single blow up to 5-die progression machines with cut-off sizes from 1/8 inch to 1 inch from global manufacturers.
The two major components of cold heading tooling are punches and dies. Punches transfer the required force from the machine to the material and provide close dimensional control on the internal part features. Dies confine and direct the material into the desired geometry and provide close dimensional control on the external part features.
CNS B 7106 - Testing standards for cold heading machines.