Importance and process of injection mold maintenance
As an important molding equipment for injection molding products, the quality of injection mold is directly related to the quality of production. Moreover, because the mold occupies a large proportion in the production cost of injection molding enterprises, its service life directly affects the cost of injection molding products. Therefore, to improve the quality of injection mold, maintain and maintain it well and prolong its service life is an important subject for injection molding products processing enterprises to reduce cost and increase efficiency.
Injection molding products processing enterprises have many product varieties and frequent mold replacement. After completing a production cycle, the molds are generally stored in the warehouse until the next production cycle comes. However, some processing enterprises do not pay enough attention to the preservation of molds, resulting in corrosion and decline in surface finish during the preservation period, resulting in reduced output and high scrap rate. Some molds are even difficult to reuse, and a large amount of funds need to be invested again to install new molds, resulting in great waste.
The data shows that the use and maintenance account for 15% – 20% of the factors affecting the service life of molds. The service life of injection molds can generally reach 800000 times, and some well maintained molds abroad can even be extended by 2-3 times. However, due to the neglect of maintenance, the service life of injection mold in domestic enterprises is relatively short, which is only equivalent to 1 / 5-1 / 3 of that in foreign countries. Due to the short service life of the die, the waste of steel processing hours and energy, as well as the impact on the output, the loss is up to billions of yuan every year.
Therefore, the maintenance of injection mold is very important, as follows:
First of all, the processing enterprise shall first equip each mold with a resume card to record and count its use, care (lubrication, cleaning, rust prevention) and damage in detail, so as to find out which parts and components have been damaged and the degree of wear, so as to provide information on finding and solving problems, as well as the molding process parameters of the mold and the materials used in the product, In order to shorten the test run time of the die and improve the production efficiency.
Secondly, the processing enterprise should test various performances of the mold under the normal operation of the injection molding machine and mold, and measure the size of the molded plastic parts. Through this information, the existing state of the mold can be determined, and the damage of the cavity, core, cooling system and parting surface can be found. According to the information provided by the plastic parts, the damage state and maintenance measures of the mold can be judged.
Then, focus on tracking and testing several important parts of the mold: the function of ejector and guide parts is to ensure the opening and closing movement of the mold and the ejection of plastic parts. If any part is stuck due to damage, it will lead to shutdown. Therefore, the lubrication of the mold ejector pin and guide post should be maintained frequently (appropriate lubricant should be selected), and the ejector pin and guide post should be checked regularly Whether the guide post is deformed and damaged on the surface. Once found, it shall be replaced in time;
After completing a production cycle, antirust oil shall be applied to the working surface, moving and guiding parts of the die, especially the protection of the elastic strength of the bearing parts of the die with gear and rack and the spring die, so as to ensure that it is always in working state;
With the continuous production time, scale, rust, sludge and algae are easy to deposit in the cooling channel, making the cross section of the cooling channel smaller and the cooling channel narrower, greatly reducing the heat exchange rate between the coolant and the mold and increasing the production cost of the enterprise. Therefore, attention should be paid to the cleaning of the channel; For hot runner mold, the maintenance of heating and control system is conducive to prevent production faults, so it is particularly important.
Therefore, after the end of each production cycle, the belt heater, rod heater, heating probe and thermocouple on the mold shall be measured with an ohmmeter. If they are damaged, they shall be replaced in time, compared with the mold resume and recorded, so as to find problems in time and take countermeasures.
We should pay attention to the surface maintenance of molds, which directly affects the surface quality of products, and the focus is to prevent corrosion. Therefore, it is particularly important to select a suitable antirust oil. After the mold completes the production task, take different methods to carefully remove the residual injection molding according to different injection molding. The residual injection molding and other deposits in the mold can be removed with copper rod, copper wire and mold cleaning agent, and then air dried.
It is forbidden to clean hard objects such as iron wire and steel bar to avoid scratching the surface. If there are rust spots caused by corrosive injection molding, use a grinder to grind and polish, spray with anti rust oil, and then store the mold in a dry, cool and dust-free place.
A pair of well maintained molds can shorten the time of mold assembly and commissioning, reduce production faults, make the production run stable, ensure the output, reduce the loss of waste products, and reduce the operation cost and fixed asset investment of the enterprise. At the beginning of the next production cycle, the enterprise can successfully produce qualified products. Therefore, for injection molding products processing enterprises, in the current fierce market competition, well maintained molds can help enterprises.
