The molding process of plastic products not only allows us to obtain the desired plastic products, but also improves the performance of plastics. For thermoplastics and thermosetting plastics, their molding methods are different. There are four plastic molding methods, injection molding, blow molding, blister molding, and extrusion molding.
1.Injection molding.
Injection molding can also be divided into injection molding molding method and die casting method. Injection molding machine, referred to as injection machine or injection molding machine, is the main molding equipment for making thermoplastic or thermosetting materials into plastic products of various shapes with plastic molding molds. Injection molding is realized through injection molding machines and molds.
Injection molding is mostly used for thermoplastics. It is similar to extrusion molding, the difference is that the molten plastic enters the closed mold through the nozzle, and solidifies and forms the product in the mold. More production of small packaging boxes, daily necessities, special-shaped parts and so on. The quality of injection molding requires that the color, size, structure, appearance, and character mark must be consistent, clean, and packaged and protected. Injection molding products are the most extensive, as long as there are molds, products can be made, and it is very convenient.
2.Blow molding.
Blow molding is mostly used for thermoplastics. The tubular plastic parison obtained by extruding the plastic is placed in the split mold while it is hot, and the air is compressed in the parison immediately after the mold is closed to inflate the plastic parison and cling to the inner wall of the mold, and it is demoulded after cooling , to obtain various hollow products. First, the molten plastic is placed in the mold, and under the pressure of compressed air, the plastic is blown up to the inner surface of the mold. Finished product after cooling and demoulding. Blow molding is mostly used to produce various hollow packaging containers, and can also produce films, sheets, etc. The quality of blow molding requires balanced thickness, uniform weight, consistent color, smooth surface and complete conformity.
3.Blister forming.
Blister is a kind of plastic processing technology. The main principle is to heat and soften the flat hard plastic sheet, then absorb it on the surface of the mold by vacuum, and shape it after cooling. It is widely used in the production of pots, plates, bowls, and plastics. Packaging, lighting, advertising, decoration and other industries. The trial product must be suitable, the buckle position can fasten the product, the thickness should be balanced, and the surface should be smooth and transparent.
4.Extrusion molding.
Extrusion, also known as extrusion, is a plastic molding process and one of the important methods for thermoplastic molding. Extrusion molding is mostly used for thermoplastics. This is to extrude the melted and plasticized plastic through the mouth gap of the mold at the head of the extruder to form a profile similar to the shape of the die. It produces more sheets, pipes, rods, wires, special-shaped materials, etc.
