The quality of die-casting mold includes the following aspects:
(1) The quality of aluminum alloy die-casting parts: the dimensional stability and conformity of aluminum alloy die-casting parts, the smoothness of the surface of the casting parts, the utilization rate of aluminum alloy, etc.;
(2) Life time: on the premise of ensuring the quality of aluminum alloy die-casting parts, the number of working cycles that the die-casting mold can complete or the number of aluminum alloy die-casting parts produced;
(3) Use and maintenance of die-casting mold: Whether it is the most convenient to use, easy to demold, and the production auxiliary time as short as possible;
(4) Maintenance cost, maintenance periodicity, etc.
Basic ways to improve the quality of die-casting molds:
1. The design of aluminum alloy die castings should be reasonable, and the best structural plan should be selected as much as possible. The designer should consider the technical requirements of aluminum alloy die castings and their structure must meet the process and feasibility of mold manufacturing.
2. The design of die-casting mold is the most important step to improve mold quality. Many factors need to be considered, including the selection of mold materials, the usability and safety of mold structure, the machinability of mold parts and the convenience of mold maintenance. , These should be considered as thorough as possible at the beginning of the design.
① Selection of mold materials
In order to meet customer requirements for product quality, it is also necessary to consider the cost of the material and its strength within the set period. Of course, the material must be selected according to factors such as mold type, working method, processing speed, and main failure modes. Because the die-casting mold is subjected to cyclic thermal stress, materials with strong thermal fatigue properties should be selected; when the castings are large in batches, quenched and tempered steel can be selected. In addition, it is also necessary to consider the use of mold materials with less affinity with castings to prevent mold sticking from aggravating the wear of mold parts, thereby affecting the quality of molds.
②When the mold structure is designed
Try to be as compact as possible, easy to operate, and ensure that the mold parts have sufficient strength and rigidity; when the mold structure allows, the corners of each surface of the mold parts should be designed as rounded transitions as much as possible to avoid stress concentration; Cavity and part of the punches and cores can be assembled or inlaid structures to eliminate stress concentration. For slender punches or cores, appropriate protection measures must be taken in the structure; for cold stamping dies, it should be configured to prevent parts or waste Blocked devices (such as ejector pins, compressed air, etc.). At the same time, it is also necessary to consider how to reduce the impact on mold quality caused by the wear of sliding fittings and frequent impact parts during long-term use.
③In the design, the scope of disassembly and assembly must be reduced when repairing a certain part, especially when the wearing parts are replaced, the scope of disassembly and assembly should be reduced as much as possible.
3. Mold manufacturing process
It is also an important part to ensure the quality of the mold. The processing method and processing accuracy in the mold manufacturing process will also affect the service life of the mold. The accuracy of each part directly affects the overall assembly of the mold. In addition to the accuracy of the equipment itself, it is necessary to improve the processing method of the parts and improve the technical level of the fitter in the mold grinding and matching process to improve the processing accuracy of the mold parts ; If the overall assembly effect of the mold does not meet the requirements, the probability of making the mold move in an abnormal state in the trial mold will increase, which will have a great impact on the overall quality of the mold. In order to ensure that the mold has a good original accuracy, in the manufacturing process, a reasonable high-precision processing method, such as electric discharge, wire cutting, CNC machining, etc., should be selected first. At the same time, attention should be paid to the accuracy of the mold, including the machining accuracy of the mold parts Assembly accuracy and comprehensive inspection of the accuracy of the mold through the mold trial acceptance work. During the inspection, it is necessary to use high-precision measuring instruments as much as possible. For those mold parts with complex surface and curved structures, ordinary straightedges and vernier cards cannot be used. For accurate measurement data, precise measurement equipment such as a three-coordinate measuring instrument must be selected to ensure the accuracy of the measurement data.
4. Surface strengthening of the main forming parts of the mold
In order to improve the surface wear resistance of the mold parts, so as to better improve the quality of the mold. For surface strengthening, different strengthening methods should be selected according to different use molds.
5. Correct use and maintenance of mold
It is also a major factor in improving the quality of molds.
For example: mold installation and debugging methods should be appropriate, in the case of hot runners, the power supply wiring must be correct, the cooling water circuit must meet the design requirements, and the parameters of the injection molding machine, die casting machine, and press in the mold production must meet the design requirements and many more.
When using the mold correctly, it is necessary to perform regular maintenance on the mold. The guide posts, guide sleeves and other parts of the mold should be filled with lubricating oil frequently. The die-casting mold should be lubricated or lifted before each mold is formed. The mold agent is sprayed on the surface of the formed part. The planned protective maintenance of the mold and the data processing in the maintenance process can prevent possible problems in the mold production and improve the efficiency of maintenance work.
Post time: Jul-21-2021