Maintenance of injection mold

​In order to judge the damage state of the injection mold and repair measures, the processing company should measure the size of the final molded plastic part and test the performance of the mold under the normal operation of the mold and the injection molding machine. Through this information, we can find out the damage of the cavity, core, cooling system and parting surface, and determine the existence of the mold.

At the same time, it is necessary to focus on tracking and testing several important parts of the Auto Parts Mold. The function of the ejector guide rail is to ensure the opening and closing movement of the injection mold and the ejection of the plastic parts. If any part gets stuck due to damage, production will be suspended. Therefore, check whether the ejector rod and guide post surface is deformed or damaged regularly, and keep the ejector rod and guide post lubricated frequently. Once a problem is found, it should be replaced in time.

After the injection mold completes a production cycle, ensure that the injection mold is always in the best working condition, pay special attention to the elastic strength protection of the bearing parts with the rack and pinion mold and the spring mold, and coat the moving, working and guiding parts of the mold Professional anti-rust oil. With the continuous extension of production time, rust, silt, scale and algae are easy to deposit in the cooling channel, which makes the cooling channel narrower and smaller, which increases the production cost of the enterprise. The heat exchange rate between the coolant and the mold is greatly increased. reduce. Therefore, attention should be paid to the cleanliness of the cooling channel.

The maintenance of the heating control system helps prevent the production failure of the hot runner mold. Therefore, after each production cycle, an ohmmeter should be used to measure the heating probe, strip heater, thermocouple and rod heater on the mold. If it is damaged, it should be replaced in time, a record should be made, and compared with the mold record, so that the problem can be found in time and countermeasures can be taken.

The surface maintenance of the injection mold directly affects the surface quality of the product, and the focus is on anti-corrosion. Therefore, it is particularly important to choose a suitable, high-quality, and professional anti-rust oil. After completing the production task, the mold should adopt different methods according to different injection molding, and carefully remove the residual injection product. When removing the residual injection and other deposits in the injection mold, you can use copper wire, copper rod and professional mold cleaning agent, and then air dry. It is strictly forbidden to clean iron wires, steel bars and other hard objects to avoid scratching the surface, polish the rust spots and spray professional anti-rust oil, and then store the injection mold in a cool, dust-free and dry place.

The fluctuation of geometric dimensions after molding is a common problem, and the temperature control of the injection mold is more complicated. The different shapes, sizes and wall thickness ratios of different molded parts have certain requirements for the cooling system, so it is usually easy to control the plastic material within the optimal flow range. Therefore, try to keep the mold at an allowable low temperature to improve production efficiency and shorten the injection cycle.

When debugging the injection mold, determine the proper matching of injection pressure and clamping force. The air in the gap formed between the cavity and the core and the gas generated by the plastic must be discharged from the exhaust groove. As long as no burrs are produced, the depth of the exhaust shoulder should be as deep as possible, and a large exhaust groove is opened behind the shoulder to allow the gas passing through the shoulder to quickly exit the mold. If there are special needs, for the same reason, an exhaust groove should be opened on the ejector rod. Due to the different shapes and sizes of some plastic parts, with changes in temperature and pressure loss after demolding, deformation and warping will occur under different conditions.