The principle of the bakelite injection molding machine is similar to that of injection needles. It relies on the thrust of the extruder screw (or plunger pump) to inject molten plastic in a molten state (that is, a viscous flow state) into a closed mold core, and then dry and fix the plastic to obtain handicrafts.
Injection molding is a cyclic process, and each cycle time includes: quantitative analysis of feeding, melting and melting, pressure injection, mold filling and water cooling, and mold opening and removal. After the plastic parts are removed, the mold is closed again for the next cycle.
Plastic machine operation items: The plastic machine operation items include three aspects: control keyboard operation, automatic control system operation of household appliances, and hydraulic transmission system operation. Perform injection process action, feeding action, injection pressure, injection speed, selection of injection form, temperature monitoring of each section of the barrel, adjustment of injection pressure and back pressure, etc.
The molding process of the ordinary screw press is as follows: first, the granular or powdery plastic is added to the barrel, and the plastic is melted by the rotation of the extruder screw and the heating of the barrel surface; then, the equipment locks the mold and advances the injection seat so that The nozzle is tightly attached to the feed channel of the grinding tool; then, pressure oil is filled into the injection barrel, so that the extruder screw is pushed forward and the molten material is introduced at very high pressure and quickly at a lower temperature in closed grinding tools. After a certain time and pressure hold (also called holding pressure), cooling with water to make it dry and solid, the artwork can be removed from the mold (the purpose of holding pressure is to prevent the molten material from flowing back into the mold core, filling the raw material into the mold core, and ensure that the artwork has a certain relative density and standard tolerance). The basic requirements of an injection molding machine are melting, injection and forming. Melting is the precondition for realizing and ensuring the quality of the formed handicrafts. To meet the requirements of forming, the injection must have sufficient pressure and speed. At the same time, due to the high injection pressure, a corresponding high pressure is generated in the mold core (the average pressure in the mold core is usually between 20 and 45 MPa), so there must be a sufficient clamping force. The reason is that the injection equipment and the mold equipment are the core components of the plastic machine.