Five Major Steps of Injection Mold Production Process

1. Process analysis of plastic products

Before mold design, the mold engineers shall fully analyze and study whether the plastic product conforms to the principle of injection molding processing, which requires detailed negotiation and consensus with the designer or customer of the plastic product. This includes the necessary discussion of the geometry, dimensional accuracy, and appearance requirements of the plastic product to avoid unnecessary complexity in the mold manufacturing process.

2. Injection Mold structure design

A set of excellent injection molds, its quality is not only derived from the advanced processing equipment and skilled mold manufacturing team, but also inseparable from the carefully designed mold structure. Especially for the complex structure of the mold, the quality of the design is directly related to the mold quality of more than 80%. An excellent mold design aims to meet the needs of customers while realizing the minimum processing cost, minimizing the processing difficulty and shortening the processing cycle.

In order to achieve this goal, we must deeply analyze and fully understand the needs of customers, at the same time, we also need to have a comprehensive and in-depth understanding of the working principle of the injection molding machine, the characteristics of injection mold structure, the processing process requirements and the processing capacity of the mold factory itself. Therefore, the key to improve the mold design level lies in the following points:

(1) In-depth analysis of each set of mold design links, to ensure a clear understanding of the use and function of each part in the mold.

(2) In the design process, we should actively refer to the previous similar design cases and learn the lessons from the mold processing and product production process, so as to optimize the current design.

(3) Understand the working principle of injection molding machine, strengthen the adaptability and coordination between mold design and injection molding machine.

(4) Go deep into the factory line, understand the characteristics and limitations of all kinds of processing technology, so as to give better play to the advantages of various processing methods in the design.

(5) Pay attention to and analyze the performance of the designed mold in the process of mold trial and mold modification, constantly summarize the experience and lessons, and improve the design level.

(6) In the design, the mold structure in previous successful cases is preferred to ensure the stability and reliability of the design.

(7) Continue to pay attention to the latest development of mold technology, research special mold structure, constantly introduce new technology, new process, improve the innovation and competitiveness of mold design.

3. Selection of mold materials and the selection of standard parts

When selecting mold materials, we need to comprehensively consider the precision requirements and quality standards of the product, and closely combine the actual processing and heat treatment capacity of the mold factory to ensure the rationality and applicability of material selection. In addition, in order to effectively improve the manufacturing efficiency and shorten the production cycle, we should make full use of the existing standard parts, give full play to their advantages of versatility and interchangeability, reduce production costs and improve production efficiency.

4. Parts fine processing and mold precision assembly

The precision of the mold not only depends on the optimal structural layout and reasonable tolerance coordination, but also depends on the exquisite skills of parts processing and mold assembly. Therefore, in the process of mold manufacturing, the control of processing accuracy and the selection of processing methods are very important, and they have a decisive impact on the overall performance of the mold.

The size error of the injection molded products mainly consists of the following parts:

(1) The error in the mold manufacturing process occupies about one-third.

(2) The error caused by wear in mold use accounts for about one sixth.

(3) The error caused by the uneven shrinkage of the molding parts accounts for about one-third.

(4) The error caused by the inconsistency between the predetermined contraction and the actual contraction accounts for about one-sixth.

The total error is the sum of the above errors.

In order to reduce the mold manufacturing error, the first task is to improve the processing accuracy. With the widespread application of CNC machine tools, this problem has been effectively controlled. In addition, for the mold with high processing accuracy and large product output, in order to prevent the error caused by the wear and deformation of the mold, the key parts such as the cavity and core should be quenching. In the design of medium and large molds, in order to save materials and facilitate processing and heat treatment, the use of patchwork structure should be given priority.

CNC Machining	EDM Processing

In order to solve the problem of uneven shrinkage and inconsistent shrinkage with the actual shrinkage, one third of the product tolerance is usually used as the manufacturing tolerance of the mold. This is done to leave enough room for subsequent adjustment to cope with possible errors in the molding process.

5. Mold trial and verification

A set of molds from design to assembly, in fact, only completed its 70%~80% of the overall manufacturing process. For key issues such as the difference between predetermined contraction and actual contraction, the smoothness of release, the cooling effect and the impact of gate size, position and shape on the accuracy and appearance of the product, we cannot be fully grasped by the design and assembly process alone. Therefore, the mold trial has become a crucial link to test the qualification of the mold and to determine the best molding process.

Mode trial is not only a comprehensive test of the mold quality, but also an important basis for selecting and optimizing the molding process. Through the trial model, we can intuitively understand the performance of the mold in the actual production, and then make targeted adjustments and improvements. Therefore, the mold trial is an indispensable step in the die manufacturing process, which ensures the stability and reliability of the die in practical application.

6. Conclusion

Through a series of meticulous steps such as mold design, material selection, part machining, assembly and mold testing, we at Alpine Mold are committed to creating high quality molds for our customers. We understand that every step of mold manufacturing is crucial, so we always adhere to the customer's needs as the guide, and constantly improve the accuracy of mold design, processing and assembly.

As a key step to check the qualification of the mold and select the best molding process, the mold trial is an important manifestation of our unremitting pursuit of quality. We believe that only the molds that have passed the rigorous trial molding process can give the best performance in actual production and provide customers with satisfactory products.

Alpine Mold, as always, will continue to provide customers with professional technology, quality service, to provide excellent mold manufacturing solutions. We look forward to working with you to create a better future!