What is the difference between a PET preform injection molding machine and a standard injection molding machine?

Usa ka propesyonal PET preform injection molding machine lahi sa sukaranan gikan sa usa ka sagad nga katuyoan nga standard injection molding machine, tungod kay kini talagsaon nga engineered aron ipahiangay sa espesyal nga pisikal ug kemikal nga mga kabtangan sa PET resin, nga dili hingpit nga ma-accommodate sa ordinaryong mga makina. Ang materyal sa PET adunay taas nga pagsuyup sa kaumog, sensitibo nga thermal degradation, ubos nga pagkatunaw sa viscosity, and strict requirements for plasticization uniformity and molding speed, all of which demand specialized machine configurations. First and foremost, the plasticizing system is completely different. PET preform machines are equipped with a dedicated low-shear screw and barrel with a length-to-diameter ratio of 24:1 sa 26:1, featuring shallow screw grooves and no dead-angle design. This structure avoids excessive shearing force that causes PET molecular chain breakage, effectively preventing melt yellowing, carbonization, and transparency reduction during high-temperature processing. Sukwahi, standard injection machine screws are designed for universal plastics like PP and ABS, generating excessive shear heat that easily degrades PET materials and produces defective preforms with yellow streaks and haze. ikaduha, the temperature control system of PET preform machines supports multi-stage precise PID constant temperature control, covering the barrel, nozzle, and mold adapter with a temperature error controlled within ±1°C. Since PET processing temperature ranges from 260°C to 285°C, even minor local overheating will trigger acetaldehyde proliferation and material aging, a problem that ordinary machines with rough temperature control cannot avoid. Dugang pa, PET preform production requires high-speed thin-wall filling and high-rigidity clamping to ensure uniform mold locking and prevent flash on multi-cavity preforms. Professional preform machines adopt reinforced high-rigidity templates and high-response fast injection systems, achieving stable high-speed filling within 0.1 segundos, while standard machines have slow injection response and insufficient clamping rigidity, leading to uneven preform wall thickness and low yield. Dugang pa, dedicated PET machines are optimized for short material residence time, with streamlined flow channels and anti-stagnation nozzle structures to reduce melt retention and degradation. They also reserve professional interfaces for supporting equipment such as dehumidifying dryers and industrial chillers, forming a complete PET molding production system. Standard injection machines lack these targeted optimizations, resulting in low production efficiency, high defective rates, and inability to meet food-grade preform production standards. In summary, ordinary injection machines can only complete simple plastic molding, while professional PET preform machines focus on high transparency, low acetaldehyde, high yield, and high-speed mass production, fully matching the strict process requirements of PET preform manufacturing.