Do you understand these methods of plastic molding?

jwell extrusion machinery said that plastic molding is an engineering technology that involves various processes that transform plastics into plastic products. One or more of the following situations often occur during the transition process, such as polymer rheology and changes in physical and chemical properties.

Injection molding

Injection molding: Also known as injection molding, its principle is to add granular or powdery raw materials into the hopper of the injection machine, and the raw materials are heated and melted into a flowing state. Driven by the screw or piston of the injection machine, the nozzle and the mold pour The system enters the mold cavity and hardens and forms in the mold cavity. Factors affecting the quality of injection molding: injection pressure, injection time, injection temperature

Injection molding is a method of producing shapes for industrial products. Products usually use rubber injection molding and plastic injection molding. Injection molding can also be divided into injection molding and die casting. Injection molding machine (referred to as injection machine or injection molding machine) is the main molding equipment for making thermoplastics or thermosetting materials into various shapes of plastic products using plastic molding molds. Injection molding is achieved by injection molding machines and molds.

advantage:

1. The molding cycle is short, the production efficiency is high, and it is easy to realize automation.

2. It can form plastic parts with complex shapes and precise dimensions, with metal or non-metal inserts.

3. The product quality is stable.

4. Wide range of adaptation.

Applications: In industrial products, injection-molded products include: kitchen supplies (garbage cans, bowls, buckets, pots, tableware, and various containers), housings for electrical equipment (hair dryers, vacuum cleaners, food mixers, etc.), toys and games , various products of the automotive industry, parts of many other products, etc.

Extrusion

jwell extrusion machinery extrusion molding: also known as extrusion molding, mainly suitable for the molding of thermoplastics, but also for the molding of some thermoset and reinforced plastics with good fluidity. The molding process is to use the rotating screw to extrude the heated and melted thermoplastic raw material from the head with the desired cross-sectional shape, then shape it by the shaper, and then pass it through the cooler to make it harden and solidify to become the desired cross-sectional shape. product.

Through the action between the extruder barrel and the screw, the material is heated and plasticized, pushed forward by the screw, and continuously passes through the head to make various cross-sectional products or semi-products. A processing method.

Process features:

1. The equipment cost is low.

2. The operation is simple, the process is easy to control, and it is convenient to realize continuous automatic production.

3. High production efficiency; uniform and dense product quality.

4. Products or semi-finished products with various cross-sectional shapes can be formed by changing the die of the die.

Application: In the field of product design, extrusion molding has strong applicability. The types of extruded products include pipes, films, rods, monofilaments, flat belts, nets, hollow containers, windows, door frames, sheets, cable cladding, monofilaments and other profiles.

Blow molding

Blow molding: The jwell blow molding machine is to clamp the molten thermoplastic raw material extruded from the extruder into the mold, and then blow air into the raw material. The molten raw material expands under the action of air pressure and sticks to the wall of the mold cavity. Combined, and finally cooled and solidified into the desired product shape.

Blow molding, also known as hollow blow molding, is a rapidly developing plastic processing method. The tubular plastic parison obtained by extrusion or injection molding of thermoplastic resin is placed in a split mold while it is still hot, and compressed air is introduced into the parison immediately after the mold is closed, so that the plastic parison is inflated and adheres to the inner wall of the mold. After cooling and demoulding, various hollow products are obtained. Blow molding is divided into film blow molding and hollow blow molding.

1. Film blow molding

Film blow molding is to extrude molten plastic from the annular gap of the extruder die into a cylindrical thin tube, and at the same time blow compressed air into the inner cavity of the thin tube from the center hole of the die to inflate the thin tube to a diameter A larger tubular film (commonly known as a bubble tube), which is coiled after cooling.

2. Hollow blow molding

According to jwell extrusion machinery, hollow blow molding is a secondary molding technology that inflates a rubber-like parison closed in a mold cavity into a hollow product by means of gas pressure, and is a method for producing hollow plastic products. According to the different manufacturing methods of the parison, hollow blow molding includes extrusion blow molding, injection blow molding, and stretch blow molding.

1) Extrusion blow molding: Extrusion blow molding is to extrude a tubular parison with an extruder, clamp it in the mold cavity and seal the bottom while it is hot, and then blow compressed air into the inner cavity of the tube blank for inflation.

2) Injection blow molding: The parison used is obtained by injection molding. The parison is left on the core mold of the mold. After the blow mold is used to close the mold, compressed air is introduced into the core mold to inflate and cool the parison. After demolding, the product is obtained.

3) Stretch blow molding: The parison that has been heated to the stretching temperature is placed in the blow mold, longitudinally stretched with a stretch rod, and transversely stretched with blown compressed air, so as to obtain the product’s method.

Application: Film blow molding is mainly used to make plastic thin molds; hollow blow molding is mainly used to make hollow plastic products (bottles, packaging barrels, watering cans, fuel tanks, cans, toys, etc.).