Discussion on the difficulty of injection mold manufacturing

In order to produce qualified injection moulds, we must improve the quality of injection moulds, what measures can improve the quality of injection moulds processing?

Cavity and core are vertical shape surface. Plastic parts of external and internal shape is formed directly by the cavity and core, these complex multiple-layered surface processing difficulty is bigger, especially within the blind groove cavity forming surface processing, using traditional machining method, not only requires workers technical level is high, the auxiliary fixture, cutting tools, and processing cycle is long.

High precision and surface quality requirements. At present, the dimensional accuracy of general plastic parts is it6-7, surface roughness RA0.2-0.1 μm, and the corresponding injection mold parts are required to achieve the dimensional accuracy of IT5-6, surface roughness Ra0.1μm below.

The roughness of the recording surface of the laser disc should reach the level of mirror processing of 0.02-0.01μm, which requires the surface roughness of the mold to reach 0.01μm or less. Long-life injection moulds are necessary to improve efficiency and reduce costs. At present, the service life of injection moulds is generally required to be more than 1 million times.

Precision injection mold to use a large stiffness of the die frame, increase the thickness of the template, increase the support column or conical positioning element to prevent the mold by pressure deformation, sometimes the internal pressure can reach 100MPa.

Ejection device is an important factor affecting the deformation and dimensional accuracy of the product, so the ejection point should be selected to make the demoulding uniform everywhere. High precision injection mold in the structure of most of the Mosaic or full Mosaic structure, which requires the mold parts of the processing accuracy, interchangeability are greatly improved.

Long process flow and tight manufacturing time. For injection parts, most of them are complete products with other parts, and in many cases are in other parts have been completed, eagerly waiting for the injection parts to be listed. Because the shape or size of the product accuracy requirements are very high, and because of the characteristics of resin materials, injection mold manufacturing is completed, but also need to repeatedly try the mold and correction, so that the development and delivery time is very tight.

Different design, different manufacturing. Mold manufacturing is not the end, but the product design is proposed by the user. Mold manufacturing designs and manufactures molds according to the requirements of the user and, in most cases, the injection production of the product is also made in other factories. In this way, the design of products, mold design and manufacturing and production of products are carried out in different places

Mold production volume is small, generally belongs to the production of a single piece, but the mold needs a lot of standard parts, large to die frame, small to thimble, these parts by a single manufacturer to complete. Plan, design, processing technology, workshop production, human resources and other information organically organized, integrated together for overall planning, so as to effectively coordinate planning and production, can effectively ensure the quality of plastic mold and delivery on schedule.

Injection mold assembly. Mold assembly is like assembly machine, every part, every screw should not make mistakes, otherwise the consequences will be quite serious, light lead to product defects, affect production, serious damage to mold completely, resulting in scrap. So the assembly of the work must be very careful. In the assembly process, we should pay special attention to the cleaning work of the mold, especially the waterway and screw hole. We must blow the iron filings inside, otherwise the customer will be very angry.

Injection moulds, like cars, may be scrapped if they are not used for a long time without maintenance. So every time after the use of the mold should be maintained, especially the rust prevention of the forming part and the rust prevention of the main action parts. Because the injection mold due to the production process to receive water, may sleep on the mold in the installation or disassembly process, so we must ensure that the mold is dry, and then brush a layer of oil.