Preform mould operates at the heart of the injection stage that produces PET preforms. The tool clamps shut with high force, creating a sealed space between each core and cavity. Hot plastic is then driven through the hot runner system and into the cavities, filling them from the gate outward. Once the packing phase ends, cooling takes over and solidifies the material against the metal surfaces. After the set cooling time, the Preform mould opens and the ejector system pushes the finished preforms free.

Core and cavity alignment determines wall-thickness uniformity. Even a small offset can create thin spots that later cause problems during blowing. Precision machining and robust guidance systems keep the two halves in register throughout the clamping and injection phases. Preform mould that holds this alignment cycle after cycle delivers preforms whose material distribution supports reliable stretch ratios. The polished surfaces also promote clean release, reducing the chance of drag marks or stuck parts.

Thermal management runs continuously during production. Cooling circuits inside the cores and around the cavities extract heat at a controlled rate. Faster, even cooling shortens cycle time while limiting internal stresses that could affect clarity or strength. Preform mould designers place the channels as close as practical to the plastic so that temperature differences across the preform stay small. Stable mould temperature also helps the neck finish hold its exact shape and thread profile.

The neck region is fully formed inside the tool. Support ledges, threads, and the sealing face are machined into the cavity inserts so that every preform leaves with a ready-to-use closure interface. Gate design balances rapid filling against the need for a small, consistent vestige. Preform mould with a well-tuned hot runner keeps the plastic at the right viscosity and prevents freeze-off or degradation inside the manifold.

On the production floor the tool repeats its sequence without variation. Clamping force, injection speed, packing pressure, and cooling time are set to match the Preform mould’s thermal and mechanical characteristics. When these parameters stay in range, the machine produces preforms of matching weight, length, and wall profile. The ejected parts drop onto conveyors or into bins and move directly to storage or to the blow-moulding line.