Screw punch is the "heart" component in cold heading technology, working under extremely harsh conditions (high impact, high stress, high friction, high temperature, high fatigue).
Screw punches are usually cylindrical stepped shafts, consisting of a working part (front end), a transition part, and a clamping part (rear end).Under the high-speed impact of the cold heading machine (hundreds of times per minute), the punch new accurately and quickly swages the head of the wire (disc) into the shape required for the screw (such as hexagonal head, round head, disc head, slotted head, inner hexagonal head, etc.).
Generally, heat treatment and vacuum quenching are used as mainstream processes to prevent oxidation and decarburization, ensure surface quality, and achieve precise tempering. Multiple tempering (usually 2-3 times) is carried out to fully eliminate residual austenite, improve toughness and dimensional stability. The selection of tempering temperature is crucial and requires a balance between hardness and toughness. In addition, it is often subjected to cryogenic treatment to further improve hardness and wear resistance, and stabilize dimensions.
The material of screw punches is usually top-grade high alloy tool steel, high-speed steel, or powder metallurgy high-speed steel/tool steel. Common choices include high-speed steel, high alloy cold work tool steel, hard alloys, etc.
Only by comprehensively optimizing all the above factors can we manufacture screw punches with long lifespan, high efficiency, and stable quality, thus meeting the needs of modern and large-scale screw production. Our technological content and value are both very high, worthy of your attention.
