PET blow molding bottle classification

Author: mgg-Plastic bottle manufacturer

The PET blow mold can be divided into two categories, one is a bottle of pressure bottles, such as filled with carbonated beverages; another type of non-pressure bottle, such as filled water, tea, edible oil, etc. The tea beverage bottle is a modified PET bottle or PET and a thermoplastic polyarylate that is blended with polyvilly methane (PEN), which is a heat bottle, which can heat 85 ° C or more; the water bottle belongs to the water bottle Cold bottle, no need for heat resistance. The heat bottle is similar to the cold bottle on the molding process.

1 Equipment At present, the manufacturer of PET automatic blow molders foreign imports mainly have France's Sidel, Germany Krones, and Domestic Fujian Chaoguan Company. Although the manufacturer is different, its equipment principle is similar, generally including the supply system, heating system, blowing system, control system, and auxiliary machine. 2 blow molding process PET bottle blow molding process.

Important factors affecting PET bottle blow molding process include bottle blank, heating, pre-blow, mold and production environment. 2.1 When the bottle blank is prepared, the PET slice is first injected into a flank, which requires the secondary recovery ratio to be too high (less than 5%), and the number of recovery cannot exceed twice, and the molecular weight and viscosity cannot be too low. Molecular weight 31000-50000, characteristic viscosity 0.78-0.85 cm3 / g). According to the National Food Safety Law, it is not allowed to use secondary recovery.

The injection molded flankon is stored above 24h. After heating, the bottle billet is not used, and it must be stored in more than 48 hours to re-heate it. The storage time of the bottle blank cannot exceed six months.

The advantages and disadvantages of the bottle billet depends largely on the advantages and disadvantages of the PET material, and should be selected by easy to inflow, easy-to-type materials, and formulate a reasonable bottle molding process. Experiments show that the same viscosity PET material forming the bottle blank, the imported material is more blow molded than domestic materials; and the same billet, the production date is different, and the blow molding can also have a big difference. The advantages and disadvantages of the bottle blank determine the difficulty of blow molding, the requirements for the bottle blank are pure, transparent, no impurities, no different color, and the length of the point and the surrounding spains.

2.2 Heating of the heating bar blank is accomplished by the heating oven, and its temperature is set by manualization, automatic adjustment. The oven is sent from the far infrared tube to the bottle blank radiation, and the thermal cycle is performed by the oven bottom fan, so that the temperature in the oven is uniform. The bottle blank moves forward while moving forward, so that the bottle blank wall is uniform.

The arrangement of the lamp is arranged in the oven and is generally "zone" glyph in the oven, and there are more than two heads. The heat of the oven is turned around the tube opening, the overall temperature setting, the oven power, and the heating of each segment are co-control. The opening of the lamp should be adjusted in conjunction with the pre-blow bottle.

It is important to make the oven play a better role, its height, cooling plate, etc. is important. If it is adjusted, it is easy to show the blast opening (the bottle mouth is large), the hardware and neck (neck is not open), etc. defect. 2.3 Pre-blowout is a very important step in two-step blowing method, which means that during the blow molding, it starts to previl at the same time, so that the bottle blank is initially in shape. The pre-blow position, pre-blowing pressure and blow flow in this process are three important process factors.