Meaning
Precision engineered assembly consisting of steel plates, cooling channels and moving components designed to shape molten resin into a finished part. High quality injection mould tooling determines the dimensional accuracy and surface finish of the final product while managing the thermal energy of the process. The complexity of the assembly depends on the geometry of the part and the required production volume.
Cavity Construction
Hardened tool steel forms the negative space that defines the external shape of the plastic moulding. Because the pressure inside the injection mould tooling can exceed ten thousand pounds per square inch, the steel must resist deformation and fatigue over hundreds of thousands of cycles. Specialized coatings are often applied to the cavity surfaces to improve part release and reduce wear from abrasive glass fibres.
Cooling Network
Drilled passages within the plates allow for the circulation of water to remove heat from the molten plastic. An efficient cooling layout in injection mould tooling accounts for the majority of the cycle time, making the thermal design a primary driver of the cost per part. Variations in cooling rate across the tool lead to warping and internal stress in the moulded components.
Steel Selection
Choosing between P20, H13 or stainless steel involves balancing the cost of the raw material against the expected life of the project. The durability of injection mould tooling depends on the grade and heat treatment of the selected metal.
