The production of a Plastic Injection Mold involves multiple precision machining and assembly stages. Each step must be carefully controlled to ensure dimensional accuracy and long-term durability.

The process begins with mold design and engineering validation. Once finalized, tool steel such as P20, H13, or S136 is selected based on production volume and material compatibility. Steel blocks are then rough-machined using CNC milling to form the basic mold structure.

After rough machining, heat treatment is applied to improve hardness and wear resistance. Hardened steels may reach 48–52 HRC depending on application requirements.

Next comes precision machining, including CNC finishing, EDM (Electrical Discharge Machining), and wire cutting. EDM is especially important for complex cavities and deep ribs where conventional milling cannot reach.

Surface finishing is another critical stage. Mold cavities may require polishing to achieve mirror-like surfaces or texturing for aesthetic requirements. Surface roughness can be controlled to Ra 0.2–0.8 μm depending on product needs.

Assembly follows machining. Core, cavity, ejector pins, sliders, and cooling components are fitted together with high precision tolerances, often within ±0.01 mm.

A professional Plastic Injection Mold Manufacturer also performs trial molding (T0, T1 testing) to verify filling balance, cooling efficiency, and ejection performance. Adjustments are made based on sample results before mass production approval.

Cooling system design is tested during this stage, ensuring uniform temperature distribution. In many molds, water channels are positioned within 10–15 mm of the cavity surface for optimal thermal control.

Finally, the mold is validated for cycle durability, often tested for tens of thousands of cycles before delivery.

This structured manufacturing process ensures that the final mold can withstand high-pressure injection forces, often exceeding 1000 bar during production cycles.