The importance of injection molding tool maintenance and maintenance process

As the most important molding equipment for injection molding product processing, the quality of injection mold is directly related to the quality of products. Moreover, since the mold occupies a large proportion of the production cost of injection molding processing enterprises, its service life directly affects the cost of injection molding products. Therefore, improving the quality of injection molds, and maintaining and repairing them to prolong their life cycle, is an important issue for injection molding product processing enterprises to reduce costs and increase efficiency.

After completing a production cycle, the molds are generally kept in storage until the next production cycle comes and then used. But some processing enterprises do not pay enough attention to mold preservation, so that the mold in the preservation period rust, surface finish decline, resulting in product quality decline, high scrap rate, some molds are even difficult to use, need to re-invest a lot of money to buy a new mold, resulting in great waste.

Data show that the use and maintenance in the mold life factors account for 15% to 20%, injection mold life can generally reach 800,000 times, some foreign mold maintenance can even be extended 2 to 3 times. But domestic enterprises due to neglect maintenance, injection mold life is relatively short, only equivalent to foreign 1/5 ~ 1/3. Due to the short life of the mold and the steel processing labor and energy waste, as well as the impact on product quality brought about by the loss of billions of dollars each year.

Therefore, the maintenance of injection molds is very important, as follows.

1. Processing enterprises should firstly equip each pair of molds with a resume card to record and count its use, care (lubrication, cleaning, rust prevention), and damage in detail, according to which it can find out which parts and components have been damaged and the degree of wear and tear, in order to provide information to find and solve problems, as well as the molding process parameters of the mold and the materials used for the product, so as to shorten the trial run time of the mold and improve production efficiency.

2. Processing enterprises should test various properties of the mold under the normal operation of the injection molding machine and mold, and measure the size of the final molded plastic parts. Through this information, the existing state of the mold can be determined to find out where the damage to the cavity, core, cooling system, and the parting surface is located, and according to the information provided by the plastic parts, the damaged state of the mold can be judged as well as maintenance measures.

3. to focus on several important parts of the mold follow-up inspection: ejector, guide parts are to ensure the mold opening and closing movement and plastic parts ejected, if any part of the damage and stuck, will lead to stop production, so should always keep the mold ejector pin, guide column lubrication (to use the most suitable lubricant), and regularly check whether the ejector pin, guide column, etc. deformation and surface damage, once found, should be replaced in a timely manner.

After completing a production cycle, apply professional anti-rust oil to the working surface, moving and guiding parts of the mold, and pay special attention to the protection of the bearing parts of the mold with gears and racks and the elastic strength of the spring mold to ensure that they are always in the best working condition.

As the production time continues, the cooling channel is easy to deposit scale, rust, silt, and algae, etc., so that the cooling channel cross-section becomes smaller and the cooling channel becomes narrower, which greatly reduces the heat exchange rate between the coolant and the mold and increases the production cost of the enterprise, so the cleaning of the channel should be paid attention to; for the hot runner mold, the maintenance of the heating and control system is beneficial to prevent the occurrence of production failure, so it is especially important.

Therefore, after each production cycle should be mold on the band heater, bar heater, heating probe, and thermocouple measurement with an ohmmeter, if there is damage, to be replaced in a timely manner, and compared with the mold resume, make a record, in order to timely find problems and take countermeasures.

4. To pay attention to the surface maintenance of the mold, it directly affects the surface quality of the product, the focus is to prevent rust, therefore, it is especially important to choose a suitable, high-quality, professional anti-rust oil. When the mold has finished the production task, it should take different methods to remove the residual injection carefully according to different injections, use the copper rod, copper wire, and professional mold cleaning agent to remove the residual injection and other deposits in the mold, then air dry.

It is forbidden to use iron wire, steel bar, and other hard objects to clean up in order to avoid scratching the surface. If there are rust spots caused by corrosive injection molding, use a grinding machine to grind and polish, and spray with professional anti-rust oil, then store the mold in a dry, cool, and dust-free place.

A well-maintained and maintained mold can shorten the mold assembly and commissioning time, reduce production failures, make the production run smoothly, ensure product quality, reduce scrap loss, and reduce the operating cost and fixed asset investment of the enterprise so that when the next production cycle starts, the enterprise can smoothly produce products with qualified quality. Therefore, for the injection molding products processing enterprises, in the current market competition is fierce, the maintenance of good molds can help the enterprise an arm.