Our Recent News

Lessons on foolproofing the mold bought for RMB 700,000

For injection molding manufacturers, molds are also the company’s bread and butter, and the quality of the molds is what many injection molding companies pay much attention to. It mainly depends on the early mold review and design work, followed by processing accuracy and mold testing. , can avoid many unforeseen problems in subsequent production. Today we mainly talk about the importance of mold prevention.

This is an example of plug and socket foolproofing. As shown in the picture below, there is a raised place on the socket. Its main function is to prevent the plug from being inserted backwards.

  1. What is fool-proof

Fool-proofing is a design method that prevents stupid people from doing wrong things, so that even stupid people will not do wrong things, so that mistakes will never happen.

In the mold design, if the insert is not foolproof, once it is reversed, the product structure will be wrong; if the core is not foolproof, if it is reversed, it will cause the mold to be crushed. This type of case is a huge mistake in mold and injection molding factories and must be avoided through fool-proof design.

  1. A heavy price

1) The story begins

I remember that time, when we were making a brand computer speaker shell, the production cycle of the mold showed that there were 103808 molds. Due to the high requirements of the product, it was required to clean the mold, maintain the thimble, inserts, rows, and points before each production. Profiles, cooling waterways, etc., after the maintenance is completed, the machine will be produced according to the original plan, until the order is completed, a total of 20000PCS.

2) There is a problem – 700,000 is gone

One month later, the company’s assembly department had assembled the product into a finished product and was about to ship it, but something unexpected happened. After the OQC inspection, with past experience and keen insight, it was found that “the product LOGO is reversed”. As shown below.

Due to assembly requirements, most of the internal parts were covered with AB glue, leaving little room for rework. It was estimated that the entire batch of products was worth more than 70W yuan, resulting in heavy losses. What’s the problem?

3) Summary of the meeting – did not do mold fool proof

After the company leaders learned of the incident, they launched an investigation into the incident. “The logo on the plastic shell is reversed. It must be a mold problem,” a quality engineer said. The manager of the mold department immediately organized a meeting:

  1. Investigate who installed the mold?
  2. How to avoid making similar mistakes next time?

After pulling out the mold maintenance order that afternoon, I found that it was an old employee with three years of service in the company. Because the mold was not fool-proofed and the company relied solely on the experience and intuition of the mold installer to make mistakes, the company would face an economic loss of 70W yuan. The main reason was that the mold was not fool-proofed.

In the field of mold design, when designing a set of molds, how can we prevent errors from happening or minimize the chance of errors?

  1. Specific “Foolproof Law” Requirements
  2. It has a structure that does not cause errors even if there is human negligence─it does not require attention.
  3. It has a structure that even a layman can do without error – no experience or intuition is required.
  4. It has a structure that will not go wrong no matter who is working or when – no specialized knowledge or high-level skills are required.

Four. Summary

If the mold had been foolproofed in advance, the company would not have faced an economic loss of 70W yuan. The loss would not only be money, but also the company’s reputation.

Scroll to Top