Packaging General Knowledge｜A brief overview of the basic knowledge of PET blow molded bottles
Manufacturing process
The bottle embryo is a kind of injection molded items. As an intermediate semi-finished product for subsequent bi-directional stretch blow molding,the neck of the preform is already shaped at the stage of injection molding, and its dimensions won't be changed during heating and stretching/blowing, the design of preform's size, weight, and wall thickness are the factors that we need to pay close attention to when we are blowing the bottles.
2. PET bottle molding
One-step process to complete the injection, drawing and blowing process in one machine is called one-step process. The one-step method is to do pulling and blowing action after the preform is cooled after injection. Its main advantages are power saving, high productivity, no manpower, reduce pollution.
Two-step method two-step method will be injected and pull blowing separation, in two machines in time, also known as injection pull blowing process. The first step is to inject the preforms with the injection molding machine. In the second step, the preforms are reheated at room temperature and then blown into bottles. The advantage of the two-step process is that the preforms are purchased for blow molding. The advantage of the two-step method is that the preforms are purchased for blow molding, which reduces the investment (manpower and equipment). The volume of preforms is much smaller than that of bottles, which is convenient for transportation and storage. Off-season production of preforms can be blown into bottles in the peak season.
2.PET bottle molding process
Product structure
1, PET material:
PET, polyethylene terephthalate, referred to as polyester. English name Polyethylene Terephthalate, by terephthalic acid PTA (terephthalic acid) and ethylene glycol EG (ethylicglycol) two chemical raw materials polymerization reaction (polycondensation).
2, general knowledge of the bottle mouth
bottle through the Ф18, Ф20, Ф22, Ф24, Ф28, Ф33 and other diameters (corresponding to the T size of the bottle), screw specifications can usually be divided into: 400, 410, 415 (corresponding to the number of threaded turns), generally we say, 400 for 1-turn screw, 410 for 1.5-turn screw, 415 for the high level of the 2-turn screw.
3, bottle body PP and PE material bottle body with solid color, PETG, PET, PVC material with transparent color, or colored transparency, translucent feeling, with solid color is relatively small. PET material bottle body is also used with available spray color. Blow molded bottles have a bump on the bottom of the bottle. The light is brighter. There is a bonded line on the bottom of blow molded bottle.
