The processing of plastic bottles
Plastic bottle molding is the process of making final plastics from polymers made from synthetic resin manufacturing plants. The processing method (usually called plastic processing) (including compression molding), extrusion (extrusion) and injection molding (injection molding), blow molding (blow molding), rolling, to go through a total pressure plastic, extrusion, injection molding, blow molding, foam molding, calendering, etc. six processes.1 、 pressing and moldingPress molding is also known as molding or pressing, and molding is mainly used for molding thermosetting resins such as phenolic resin, urea formaldehyde resin and unsaturated polyester resin.2. ExtrusionExtrusion, also known as extrusion molding, is the use of extruders (extruders) to heat the resin continuously through the mold extrusion of the desired shape of the product. Extrusion is sometimes also used in the forming of thermosetting plastics and can be used in the moulding of foamed plastics. The advantage of extrusion is that it can extrude various shapes of products. The production efficiency is high, it can be automated and continuous production. The disadvantage is that thermosetting plastics can not be widely used in this process, and the size of products is prone to deviation.3, injection moldingInjection molding is also called injection molding. Injection molding is the use of injection molding machines (or injection machines) to inject thermoplastic melts at high pressure into the mold and to cool and cure the products. Injection molding can also be used for moulding thermosetting plastics and foams. Injection molding has the advantages of fast production, high efficiency, automatic operation, and complicated shape. It is especially suitable for mass production. The disadvantage is that the equipment and mold cost is high, the injection molding machine cleaning more difficult.
4, blow moldingBlow molding is also called hollow blow molding or hollow molding. Blow molding is a method of expanding a hot resin parison that is closed in the mold by means of the pressure of the compressed air to blow it into hollow products. Blow molding includes blow molding, film and blow molding, two methods. Blow molding can be used to produce film products, bottles, casks, pots, containers, and children's toys.5, calenderingCalendering is resin close by various additives expected (kneading and filtering) through the calender of two or more in favor of the opposing calender roll gap is processed into a film or sheet, then from the calender roller peeling off, and then by a molding method for cooling and shaping. Calendering is mainly used in the molding process of PVC resin. It can make films, sheets, plates, artificial leather, floor tiles and other products.6, foaming moldingFoaming materials (PVC, PE and PS etc.) incorporate proper foaming agents to produce microcellular structures. Almost all thermosetting and thermoplastic plastics can be made into styrofoam bottles. According to the pore structure is divided into open celled foams (feel most connected with each other and closed cell foam pores) (most pores are separated from each other), which is mainly composed of manufacturing methods (including chemical foaming, physical foaming and foaming machine) decision.
The production process of plastic bottle has two kinds: the first kind is extrusion blowing process, the plastic raw materials into the extruder, the melting extruding molten parison, then put the bottle mold blow molding, cooling after removed from the mold, eliminating waste edge to be finished after. This process is mainly used to produce polyethylene, PVC plastic bottles, such as milk bottles, soy sauce bottles and so on. The second is the plastic material injection stretch blow molding process, the injection molding machine injection molding tubular billet, then put the bottle mould through stretch blow molding, cooling after the finished product is obtained. This process is mainly used to produce PET plastic bottles, such as mineral water bottles and so on.
