Process analysis of plastic products.
In the mold design, the designer should make full analysis of its plastic products in accordance with the principle of injection molding processing, and the designers need to carefully negotiate with the products, has reached a consensus. Including the geometry of the product, the size of the accuracy and appearance requirements, the necessary discussion, as far as possible to avoid unnecessary complexity of the mold manufacturing.
Two, mold structure design.
A set of high-quality mold, not only need to have good processing equipment and skilled manufacturing workers, another important factor is to have good mold design, especially for complex mold, mold design quality accounted for more than 80% of the die quality. A good mold design is: to meet the requirements of the premise of the guests, so that the processing cost is low, the processing difficulty is small, the processing time is short. To do this, not only to fully digest the request of the guests, but also to understand the injection molding machine, mould structure and processing technology and the processing ability of mould factory. Therefore, to improve the level of mold design, we should do the following:
1 understand each every detail in the design of the die, the purpose of each parts in the mold to understand.
2 in the design of multiple reference to the previous similar design, and to understand the situation in its mold processing and product production, drawing on the experience and lessons.
3 understanding of the working process of the injection molding machine, in order to deepen the relationship between the mold and injection molding machine.
4 under the factory to understand the processing of processing products, understanding of the characteristics and limitations of each processing.
5 understand the design of the mold of their own test results and to change the situation, drawing lessons.
6 in the design as far as possible before the successful use of the mold structure.
7 more understanding of the impact of the mold into the water on the products.
8 to study some special mold structure, to understand the latest mold technology.
Three, determine the mold materials and ion of standard parts.
In the ion of die materials, in addition to considering the precision and quality of the product, but also combined with the mold factory processing and heat treatment of the actual capacity to give the correct choice. In addition, in order to shorten the manufacturing cycle, as far as possible the use of existing standard parts.
Four, parts processing and mold assembly.
In addition to the mold's precision in the design of the optimal structure and reasonable tolerance, parts processing and mold assembly is essential. Therefore, the machining precision and machining method of choice in the mold manufacturing occupies an absolute dominant position. The size error of molding products is mainly composed of the following parts:
1 mold manufacturing error is about 1/3
2 die wear caused by the error is about 1/6
3 the error caused by the shrinkage of the molded part is about 1/3
4 the error caused by the difference between the and the actual contraction is about 1/6
Total error = (1) + (2) + (3) + (4)
Therefore, in order to reduce the mold manufacturing error, the machining accuracy should be improved first. With the use of the numerical control machine tool, the problem has been well controlled. In addition, in order to prevent the mold wear and deformation caused by the error, in the processing of high precision and product yield larger mold, the mold cavity, core and other key parts should be treated with quenching. In order to save material and easy to process and heat treatment, the mould design should be used as far as possible. In order to solve the error of molding the uneven shrinkage and shrinkage and shrinkage of the actual predetermined inconsistency, generally ed products in the mold manufacturing tolerances of 1/3, as the mold manufacturing tolerances, the purpose is to process for future have greater room for adjustment, in order to solve the error caused by the forming process.
Five, test mode.
A set of mold from the beginning to the end of the assembly is completed, but complete its entire manufacturing process 70%~80%. For a predetermined error shrinkage and actual shrinkage inconsistency, demoulding smoothly or not, the cooling effect, especially the size, location, shape of gate effect on the accuracy of products and the appearance of the problem, must pass the test mode to test. Therefore, the test model is to test the quality of the mold and the ion of the best molding process is an indispensable step.