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

A professional PET preform injection molding machine differs fundamentally from a general-purpose standard injection molding machine, as it is uniquely engineered to adapt to the special physical and chemical properties of PET resin, which ordinary machines cannot fully accommodate. PET material features high moisture absorption, sensitive thermal degradation, low melt 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 до 26:1, featuring shallow screw grooves and no dead-angle design. Ова структура избегава прекомерну силу смицања која изазива ломљење ПЕТ молекулског ланца, ефикасно спречава жутило растопа, карбонизација, и смањење провидности током обраде на високим температурама. Насупрот томе, Стандардни вијци за машине за ињектирање су дизајнирани за универзалне пластике као што су ПП и АБС, ствара прекомерну топлоту смицања која лако разграђује ПЕТ материјале и производи неисправне предформе са жутим пругама и измаглицом. Drugo, систем контроле температуре ПЕТ машине за преформу supports multi-stage precise PID constant temperature control, covering the barrel, млазница, 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. Штавише, 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 секунди, while standard machines have slow injection response and insufficient clamping rigidity, leading to uneven preform wall thickness and low yield. Додатно, 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. Укратко, 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.