Hot Runners
Hot runner systems are temperature‑controlled melt delivery systems used in injection molding to convey molten polymer from the machine nozzle to individual cavity gates without solidifying. They consist of heated manifolds, nozzles, valve pins, heaters, and sensors that maintain consistent melt temperature and flow. Materials processed include PP, PE, ABS, PC, PA, POM, PET, and glass‑ or mineral‑reinforced compounds. Tooling design focuses on thermal balance, leak‑free sealing surfaces, precise gate control, and wear‑resistant components, especially for abrasive or high‑temperature polymers. Valve‑gated systems provide accurate filling, reduced stringing, and improved surface appearance, while open nozzles offer simplicity and high‑speed capability. Hot runners reduce material waste by eliminating cold runners, improving cycle times, and enhancing part quality. They are widely used in high‑volume applications such as packaging closures, automotive interior and exterior components, medical devices, consumer electronics housings, and multicavity molds where consistent gating and high productivity are essential.