Plastic injection moulds are the most important moulding equipment in the processing of injection moulded products. The quality of plastic injection moulds is directly related to the quality of products. Moreover, because the mold occupies a large proportion in the production cost of injection processing enterprises, its service life directly affects the cost of injection products. Therefore, improving the quality of injection moulds, maintaining and maintaining them well and prolonging their service life are important issues for plastic injection moulding processing enterprises to reduce costs and increase efficiency.
Plastic injection products processing enterprises because of the variety of products, mold replacement is more frequent, after completing a production cycle, the mold is generally stored in storage until the next production cycle comes out to use. However, some processing enterprises do not pay enough attention to the preservation of moulds, which results in the corrosion of moulds and the decrease of surface finish during the preservation period, resulting in the decline of product quality and high rejection rate. Some moulds are even difficult to reuse, and a large amount of funds need to be re-invested to replace new moulds, resulting in great waste. The data show that the service life of injection moulds accounts for 15%-20% of the influencing factors. The service life of injection moulds can generally reach 800,000 times. Some well-maintained moulds abroad can even be extended by 2-3 times. However, due to neglect of maintenance in domestic enterprises, the service life of plastic injection moulds is relatively short, which is equivalent to only 1/5-1/3 of that in foreign countries. Due to the short service life of the die, steel processing time and energy waste, as well as the impact on product quality caused by the loss of billions of yuan annually. Therefore, the maintenance of injection moulds is very important.
Plastic injection mould technology content is very high, there are many parts. If we do not pay attention to the maintenance of various parts in the use process, it is very easy to damage and rust, resulting in tens of thousands or even millions of yuan of economic losses. Therefore, special attention should be paid to the maintenance and maintenance of the mould in the use process to ensure the long-term use quality of the mould. For this reason, processing enterprises should first equip each die with a resume card to record and count its usage and damage in detail. According to this, we can find out which parts and components have been damaged and the degree of wear and tear, so as to provide information for finding and solving problems, as well as the moulding process parameters and the materials used in the products, so as to shorten the moulding process. The test run time of the mould can improve the production efficiency.
Secondly, the processing enterprises should test the various properties of the injection moulds under the normal operation of the injection moulding machines and moulds, and measure the size of the moulded parts. Through these information, the existing state of the moulds can be determined, and the damages of the cavity, the core, the cooling system and the parting surface can be found out. According to the information provided by the moulds, it can be done. Judge the damage status of the die and maintenance measures.
Thirdly, we should focus on tracking and testing several important parts of the die. The function of ejection and guide parts is to ensure the movement of die opening and closing and the ejection of plastic parts. If any part of them is stuck due to damage, it will lead to stop production. Therefore, it is necessary to check whether the ejection rod and guide rod have deformation and surface damage. Once found, they should be replaced in time. After completing a production cycle, anti-rust oil should be applied to the moving and guiding parts, especially the bearing parts with gears and rack dies, and the elastic strength of spring dies, so as to ensure that they are always in working state. In addition, the cleaning of cooling duct is of great importance to production efficiency and product quality. With the continuous production time, the cooling passage is easy to deposit scale, rust, sludge and algae, which makes the section of the cooling passage smaller and the cooling passage narrower, greatly reduces the heat exchange rate between the coolant and the die, and increases the production cost of enterprises. Therefore, the cleaning of the cooling passage should be paid attention to. For the hot runner die, the maintenance of heating and control system is helpful to prevent production failure, so it is particularly important. Therefore, the belt heater, rod heater, heating probe and thermocouple on the die should be measured by ohmmeter after each production cycle. If there is any damage, it should be replaced in time, and compared with the die resume to make a good record, so that problems can be found in time and countermeasures can be taken.
Fourth, attention should be paid to the surface maintenance of plastic injection moulds, which directly affects the surface quality of products, focusing on preventing rust. When the die is finished, the residual injection moulding should be carefully removed by different methods according to different injection moulding. Copper rods, copper wires and soap water can be used to remove the residual injection moulding and other deposits in the die, and then air-dried. It is forbidden to clean hard objects such as iron wire and steel bar so as to avoid scratching the surface. If there are rust spots caused by corrosive injection moulding, grinding and polishing with a grinding machine, and coated with anti-rust oil, then the mould is stored in a dry, cool, dust-free place.
A pair of molds after good maintenance and maintenance can shorten the assembly time, test run time, reduce production failure, make production run smoothly, ensure product quality, reduce waste losses, and reduce the operation cost and fixed assets investment of enterprises. When the next production cycle begins, enterprises can smoothly produce quality. Qualified products. Therefore, for injection products processing enterprises, in the current fierce market competition, maintaining a good mold can help enterprises.
