Practical ideas for inspection during injection mold manufacturing

2021-03-23 16:30:47 admin

Practical ideas for inspection during injection mold manufacturing




The inspection process of injection mold manufacturing is not a simple matter. The problem of precision inspection is that the inspector needs to know and understand the cooperation and function of the mold parts. Few people really understand this in the production of injection molds.


To some people, this sounds a bit condescending, but it is just a simple question of experience, not a manifestation of the skills and abilities of the inspector. As precision measurements become less subjective, tools become easier to use and processes become more reliable.


Donghui Precision Measurement


Most tool manufacturers pride themselves on being able to perform highly accurate measurements on the mold parts they manufacture. Over time, they learned the feel of a personal micrometer, knew that their dial gauges read slightly differently from one direction to another, and could tell when something went wrong.

This method is very effective when you are making disposable parts or custom injection molds, and these molds can only be completed by a few mold manufacturers. The communication between the two injection mold manufacturers is relatively easy, and they know where to adjust the differences to make the mold run normally.

When the mold has multiple cavities (such as 16, 32, or 64), this doesn't work at all. A single hole quickly becomes a high hole.

Latest check

Obviously, tool makers still need skilled precision measurement, but the mold manufacturing process has become an expert and almost perfectly matched part. This production-like process requires adjustments and compliance with standards in order to keep everything running normally.

It is common to outsource various components, even on a global scale. This requires everyone to use the same standards, and no matter where the parts are manufactured, the inspection process is at least similar. In some ways, it doesn't matter whether the parts are manufactured across factories or across oceans. Precision inspection tools

Precision micrometer

Dial indicator

Granite panel

Depth micrometer

Digital caliper

Measuring pin

Gauge block

Optical comparator

Coordinate measuring machine

Sine board

T transfer rack or surface gauge

Height gauge

visual system

These are several precision measuring tools commonly used in injection mold manufacturing and inspection departments. In fact, most of these tools are found in stores, and tool makers use them every day.


Internal inspection

Having a dedicated internal inspector is a very good idea for several reasons. First, it makes mold makers honest; second, it makes everyone stand on the same stand. With an impartial inspector, tool manufacturers should be more vigilant about quality and obtaining accurate dimensions.

The typical question for internal inspectors is to understand what is to be measured and what is important. The design of the injection mold usually has very close tolerances for meaningless dimensions, such as the location of the secondary vent or the depth of the core pin.

The inspector may not know or understand that once the pad may be within 0.005 inches, it works normally, but the tolerance on the printed matter may be +-.0002 inches. In order for this process to be successful, there are many such situations that need everyone to understand.

With the passage of time and training, full-time inspectors have a positive impact on the quality of the work and at the same time make the communication between each department in the workshop better.

The CNC milling department needs to ensure that its work is completed accurately, the surface grinder must maintain the required close tolerances, and the EDM operator must ensure that its work is completed as designed. Then, when the injection molding machine assembles the tools, each part fits together perfectly, and manual assembly becomes a very small part of the whole process.