Injection molding machine

- Feb 27, 2018-

Basic type 

       The types of injection molding machines are: vertical, horizontal, all-electric, but no matter the type of injection molding machine, its basic function is to have two (1) heated plastics that bring it to a molten state (2) Make it injection and fill the mold cavity. 

       Collapse edit this section of the working principle Injection molding machine works with the injection syringe with a similar, it is by the screw (or plunger) of the thrust, the plasticized good state of the molten state (ie viscous flow) of plastic injection into a closed cavity, After curing stereotypes obtained products process. 

        Injection molding is a cyclical process, each cycle includes: quantitative feeding - melt plasticization - pressure injection - filling cooling - Kai removal. Remove the plastic and then closed mold, the next cycle. Injection molding machine operation items: injection molding machine operation items include the control of keyboard operation, electrical control system operation and hydraulic system operation in three areas. Respectively, the injection process action, feeding action, injection pressure, injection speed, ejection type selection, barrel temperature monitoring, injection pressure and back pressure adjustment.

       General screw injection molding machine molding process is: first granular or powdered plastic added to the barrel, and by rotating the barrel and the outer wall of the barrel to make the plastic into a molten state, and then the machine mold clamping and injection seat forward, So that the nozzle close to the mold gate, and then to the injection cylinder through the pressure of oil, the screw forward, so as to high pressure and faster speed of the melt into the lower temperature of the closed mold, after a certain Time and pressure to maintain (also known as packing), cooling, curing it, you can open the mold to remove the product (packing pressure is to prevent the mold cavity reflow, to the mold cavity to replenish materials, and to ensure that products With a certain density and size tolerances). The basic requirements of injection molding plasticizing, injection and molding. Plasticization is to achieve and ensure the quality of molded products premise, and to meet the molding requirements, injection must ensure that sufficient pressure and speed. At the same time, due to the high injection pressure, a correspondingly high pressure is generated in the mold cavity (the average pressure in the mold cavity is generally between 20 and 45 MPa) and therefore a sufficient clamping force must be obtained. Thus, the injection device and clamping device is a key component of the injection molding machine.

        The evaluation of plastic products are mainly three aspects, the first is the appearance of quality, including integrity, color, gloss, etc .; the second is the accuracy of the size and relative position; the third is the use of the corresponding physical properties, chemical properties, Electrical properties. These quality requirements and products according to different occasions, the required standard is different. Product defects mainly in the mold design, manufacturing accuracy and degree of wear and so on. However, in fact, technicians in plastic processing factories often suffer from the difficult situation of using the technological means to make up for the problems caused by mold defects.

          The process of production process regulation is to improve product quality and production of the necessary ways. As the injection cycle itself is very short, if the process conditions are not good, there will be an endless stream of waste. When adjusting the process, it is best to change only one condition at a time and observe more than one time. If the pressure, temperature and time are all adjusted together, it is easy to cause confusion and misunderstanding. Measures to adjust the technology, means are many. For example, there are more than a dozen possible solutions to the problem of dissatisfaction with products. To solve one or two major solutions to the crux of the problem, we can really solve the problem. In addition, we should pay attention to the dialectical relationship in the solution. For example: products appear depression, and sometimes to increase the material temperature, and sometimes to reduce the material temperature; sometimes to increase the amount of material, and sometimes to reduce the amount of material. To recognize the feasibility of countermeasures to solve the problem.