Vented injection exhaust type injection molding applications, the barrel is arranged in the middle part of the exhaust port is connected with the vacuum system, when the plastic plastic, plastic vacuum pump can be in some water vapor, monomer, volatile substances and air through the exhaust port away; raw material without pre drying, so as to improve the production efficiency to improve the quality of the products. It is especially suitable for the molding of polycarbonate, nylon, organic glass, cellulose and other moisture absorbing materials.
The flow injection molding can be used as an ordinary moving screw injection machine. That is, plastic is continuously plasticized and squeezed into a mold cavity with a certain temperature. After the plastic cavity is filled, the screw stops rotating, and the material in the mold is kept at a proper time under pressure for the purpose of cooling and setting. The flow injection molding overcomes the equipment limitation for the production of large products, and the quality of the parts can exceed the maximum injection quantity of the injection machine. The feature is that the plasticized objects are not stored in the barrel but are constantly squeezed into the mold, so it is a method of combining extrusion and injection.
Co injection molding is made by injecting machine with two or more injection units, and injecting different kinds of plastics with different colors into the mold at the same time or successively. This method can produce a variety of color and / or multiple plastic composite products. The representative co injection molding is double color injection and polychromatic injection.
In the mold, the diverting channel is not set, and the melting material is directly injected into each mold cavity by the extension nozzle of the injection machine. During the injection process, the plastic in the flow channel keeps the flow state of the melt, and is not separated from the product in the mold release, so there is no debris in the flow passage. This method not only saves the raw material, reduces the cost, but also reduces the process, and can achieve full automatic production.
The principle of reaction injection molding is to measure the raw material after metering by the metering device, then pump it into the mixing head, and then mix and mix in the mixing head, then high-speed injection into the closed mold, fast curing, demoulding, and taking out the product. It is suitable for processing some thermosetting plastics and elastomers, such as polyurethane, epoxy resin, unsaturated polyester resin, organosilicon resin, alkyd resin and so on.