1. Preparation of bottle preforms For injection molding of the first PET slice, it takes twice the proportion of recycled material not too high (less than 5%), no more than twice recovery, with molecular weight and viscosity not too low (for 31000 -50000, molecular weight viscosity 0.78-0.85 cm3 / g). Injection preforms should be stored for 48 hours or more. Preform, do not use after heating, must be reheated before 48h. Bottle storage time does not exceed six months.
2, heating, heating the preform to complete the furnace, the temperature set by manual, automatic adjustment. Far infrared radiation heating preform using far infrared light oven, the bottom of the oven by the fan thermal cycle, the oven temperature uniform. Preform in the oven while rotating, the bottle wall heated evenly.
3, pre-blowing, blowing process is a two-step process is a very important step. It refers to the same time in the fall of the pumping air, so that the shape of the bottle set first. The pre-blowing position, pre-blowing pressure and blowing air flow are three important technical factors in this process.