My Understanding of the mold

Original author: EMM- Kenny         Date: 2023-8-16

I have been working in the mold industry for 20 years. From mold processing, mold designing, project management, and I finally operate and manage mold factories on my own. Participated in the publicity of Foxconn's standardized mold manufacturing process, I have visited many mold factories including public-listed companies and small-sized mold processing plant. Everyone's desire for top-end mold quality is consistent, but the problems encountered relating to quality are diversified.

Different person holds different perception of the mold. The mold companies with sufficient fund import a large number of advanced equipment in order to ensure good mold quality. Some small factories do not have advanced processing equipment and they rely on quality inspection departments to strengthen testing in order to ensure good mold quality, but often backfire. I visited these mold factories and came to the following conclusions:

First, the advanced manufacturing equipment alone can not guarantee that it can produce a good quality mold, because the ability of CAM will also affect the processing quality of the mold, and the rational structure design will affect the smoothness of the entire mold.

Second, relying on testing can reduce bad quality, but can not solve the fundamental problems. When the defective rate exceeds the standard, the whole factory will be in a vicious circle of maintenance and repair, bringing huge cost pressure to the factory operation. The real quality is manufactured but not detected.

In order to provide customers with good mold quality, I think we should work from the following points:

1, Recognize the mold and understand the mold. 

Mold is a living "person" with a lot of organs. The relation between organs is the perfection degree of tolerance between parts. A long-lived person must have a healthy organ tissue, and a high-quality mold must have a reasonable tolerance of the parts.  If the cumulative tolerance of each part assembled together can be completely eliminated, then the operation of the mold must be very smooth, and the production will be smoother until the life of each part reaches the end of the material life.

2, Mold design and manufacturing is a high-tech subject and is also a job that people can survive by experience. 

Some engineers adopt smaller injection molding machine in order to minimize the mold size and reduce the amount of mold material, resulting in a discount of mold life. Some engineers would like to secure the life of the mold as well as the mold strength, and increase the additional material consumption of mold parts. As a result, the mold is too large to match a larger injection molding machine to complete the production, together with the additional occurred costs of material and processing. 

With the absence of theoretical calculation and scientific basis, engineer’s blind design by experience alone can not guarantee high technology and high quality mold. Each part will be subject to the force of all parties in the mold operation, the degree of force determines the strength of the material required by the part. 

An excellent mold designer must know how much force each part will bear in the mold operation, how much torque, the maximum pressure during molding, the maximum pressure transmitted to the mold, and how many degrees the mold temperature rises to have an impact on the strength of the mold? These can be obtained through the theoretical scientific data of material mechanics and material application.

Only by in-depth study of the dialectical relationship between the mold parts can we design a better and more scientific mold, ensuring the quality of the mold and saving the cost of the mold. At the same time, mold manufacturing also needs the guidance of material mechanics and metal processing technology disciplines. When processing mold parts in different processes, different stress will be released. Improper handling will lead to mold deformation, and even unnecessary scrap parts. 

How much impact of chip force on the material metallographic structure? What is the metallographic structure of the material after heat treatment? What kind of tool to be chosen for processing? The carbon accumulation phenomenon during EDM processing. The stress released during the wire-cutting processing, etc. All require the guidance of the discipline and the accumulation of experience. Theory guides practice, and practice promotes continuous innovation of theory, so that the mold industry can be regarded as a high-tech industry.

3, With a correct understanding of the mold, we then know how to design and manufacture the mold.

Reasonable structural design can help manufacturing save a lot of processing costs. Processing skills mastered by engineers and the mold structure mastered mold manufacturing workers can avoid cost waste because of the unreasonable process and structure.

4.Master the characteristics of each mold manufacturing process, give full play to the advantages of each process, and rationally arrange the manufacturing process to ensure the quality and delivery of the mold.

5, Unified the mold concept among staffs.

Only the design and manufacturing concept reached agreement within the team, the mold quality manufactured is guaranteed from such a highly consistent team.

6, In order to improve the quality and life of the mold, it is necessary to establish the traceability of the flow process for each mold part.

The processing technology and manufacturer information of each part should be fully traceable during the mold quality warranty period so as to trace the root cause of the abnormal quality when it occurs, and deeply investigate the root cause of the abnormal quality. Only by following this, the mold quality is truly guaranteed from design, manufacturing to putting into use.

This article is for peer knowledge exchange. Intellectual property rights are protected. Do not copy without my written permission!