Such as hot runner mold, plastic dryer, mold chiller, perform removal robot, perform conveyor belt and injection environment control air conditioner dehumidifier Etc. In the whole preform processing equipment, in addition to the injection molding machine, other interface equipment is required. The temperature of the dryer is set between 177 degrees and 182 degrees and dried for about four hours. The dew point temperature must be between -29 ° C (-200 ° F) and -40 ° C (-400 ° F). The part of the embryo is crystallized and white, which affects the quality of the product.īefore the preform is injection molded, the PET pellets must be dried to a moisture content of 0.005% or less, in order to produce a good amorphous transparent preform. The physical and mechanical properties will be reduced, the crystallization rate will be increased, and the bottle will be produced when the preform is injected. If the water content is too high, hydrolysis will occur under high-temperature processing, and the PET molecular chain will be broken and thermally decomposed to produce acetaldehyde. Nowadays, PET is recycled and then woven into silk to make other kinds of products, such as clothing, bag, etc. Reusable: In 1984, the Continental Can Company requested Coca-Cola to develop PET containers by replacing glass bottles with PET.Heat-resistant filling: PET can be filled at 70~90 ☌, and it also increases gas barrier.Good mechanical properties: including gas barrier, transparency, gloss, impact resistance, toughness, lightweight, chemical resistance, and easy processing.They also prevent carbon dioxide gas and keep the soda air. PET plastics are light in weight, high in transparency, resistant to impact and easy to break.Advantages of PET preformsīecause PET (polyethylene terephthalate) has good mechanical properties, heat-resistant filling, and re-use, it is widely used: Containers such as edible oils, cosmetics, detergents, and candy can, and have widely replaced containers such as PVC bottles or glass bottles. Such as mineral water, tea drinks, sodas. PET materials have been developed for more than 35 years, and their application has been widely used in canned containers around the world. PET materials were first used in eye drops in Japan in 1975. When the bottle is to be blown, it is sent to the hollow molding machine to heat the preform to the blowing temperature, and then blown and cooled. The preforms are firstly formed by the injection molding machine, and the preforms are cooled to a solidification temperature and are taken out and cooled to room temperature The cold embryo type method, also known as the two-step method, is that after the pre-forming and the blow molding are respectively performed by different machines The preformed preform is cooled to a temperature lower than the crystallization temperature but remains in a thermoelastic state. The hot type embryo method, also known as the one-step method, can be used only from one molding machine from the beginning of the preforming to the blow molding. Injection molding is divided into two types: thermal type embryo method and cold type embryo method. This bottle making method is called a two-step method, that is, forming preforms by injection molding, again Method for forming PET plastic bottle by blow molding bottles for cosmetics, medicine, health care, beverages, mineral water, reagents, etc.Injection Molding and blowing: PET preforms are re-processed by blow molding to form plastic bottles, including:.Direct blowing: The molten PET plastic is blown into the cavity and blown, and the common blow molding machine is blow molded in this way. It has been widely used in various food containers.
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