There are several classifications of plastic molds. Introduction to knowledge of plastic molds
Plastic mold, abbreviated as a combination plastic mold used for compression molding, extrusion molding, injection molding, blow molding, and low foaming molding.

1、 Plastic mold county structure
It mainly includes a concave mold with a variable cavity composed of a concave mold combination substrate, a concave mold component, and a concave mold combination card plate, and a convex mold with a variable core composed of a convex mold combination substrate, a convex mold component, a convex mold combination card plate, a cavity cutting component, and a side cutting combination plate. Coordinated changes between convex and concave molds and auxiliary forming systems. Can process series plastic parts of different shapes and sizes.
In order to improve the performance of plastics, various auxiliary materials such as fillers, plasticizers, lubricants, stabilizers, colorants, etc. need to be added to the polymer in order to become high-performance plastics.

1. Synthetic resin is the main component of plastics, with a content generally ranging from 40% to 100%. Due to its high content and the fact that the properties of resin often determine the properties of plastics, resin is often regarded as a synonym for plastic. For example, mixing polyvinyl chloride resin with polyvinyl chloride plastic, phenolic resin with phenolic plastic. In fact, resin and plastic are two different concepts. Resin is an unprocessed raw polymer that is not only used to manufacture plastics, but also as a raw material for coatings, adhesives, and synthetic fibers. Except for a very small portion containing 100% resin, the vast majority of plastics require the addition of other substances in addition to the main component resin.

2. Fillers, also known as fillers, can improve the strength and heat resistance of plastics while reducing costs. For example, adding wood powder to phenolic resin can greatly reduce costs, making phenolic plastic one of the cheapest plastics and significantly improving mechanical strength. Fillers can be divided into two categories: organic fillers and inorganic fillers. The former includes wood powder, rags, paper, and various textile fibers, while the latter includes glass fiber, diatomaceous earth, asbestos, carbon black, etc.

3. Plasticizers can increase the plasticity and softness of plastics, reduce brittleness, and make plastics easy to process and shape. Plasticizers are generally high boiling organic compounds that are miscible with resins, non-toxic, odorless, and stable to light and heat. The most commonly used are phthalates. For example, when producing polyvinyl chloride plastics, if a large amount of plasticizer is added, soft polyvinyl chloride plastics can be obtained. If no or less plasticizer is added (dosage<10%), hard polyvinyl chloride plastics can be obtained.

4. To prevent the decomposition and damage of synthetic resins by light and heat during processing and use, and to extend their service life, stabilizers should be added to plastics. Commonly used include stearates, epoxy resins, etc.

5. Colorants can give plastics various bright and beautiful colors. Organic dyes and inorganic pigments are commonly used as colorants.

6. The function of lubricants is to prevent plastics from sticking to metal molds during molding, while also making the surface of plastics smooth and aesthetically pleasing. Common lubricants include stearic acid and its calcium magnesium salts. In addition to the above-mentioned additives, flame retardants, foaming agents, anti-static agents, etc. can also be added to plastics.

2、 Classification of plastic molds

A. Injection molding mold - TV casing, keyboard buttons, electronic products, computer peripheral plastic products, toys, household products (most commonly used)
B. Blowing mold - beverage bottles
C. Compression molding mold - Electric wood switch, scientific ceramic bowl and dish D. Transfer molding mold - Integrated circuit products
E. Extrusion molding mold - Glue tube, plastic bag F. Hot forming mold - Transparent formed packaging shell G. Rotating molding mold - Soft rubber doll toy III. Precautions

（1） Don't just focus on product design and neglect plastic mold manufacturing.
Some users, when developing products or trial producing new products, often focus only on product research and development in the initial stage, neglecting communication with plastic mold manufacturing units. After the initial determination of the product design plan, contacting the mold manufacturer in advance has two benefits:

1. It can ensure that the designed product has good forming technology and will not be modified due to the difficulty of machining the parts. 2. The mold maker can make design preparations in advance to prevent hasty and thoughtless considerations that may affect the project schedule.
3. Making high-quality plastic molds requires close cooperation between supply and demand in order to ultimately reduce costs and shorten the cycle.

（2） Don't just look at the price, consider quality, cycle, and service from all aspects.
1. There are many types of molds, which can be roughly divided into ten categories. Select different types of molds for forming based on different requirements such as part materials, physical and chemical properties, mechanical strength, dimensional accuracy, surface smoothness, service life, and economy.
2. High precision molds require the use of high-precision CNC machine tools for processing, and there are strict requirements for mold materials and forming processes. CAD/CAElCAM mold technology is also needed for design and analysis.
3. Some parts require advanced processes such as hot runner, gas assisted molding, and nitrogen cylinder due to special requirements during molding.
4. Manufacturers should have CNC, EDM, wire cutting machines and CNC profile milling equipment, high-precision grinding machines, high-precision three coordinate measuring instruments, computer design and related software, etc.
5. Generally, large stamping molds (such as automotive cover parts molds) need to consider whether the machine tool has an edge pressing mechanism, even edge lubricants, multi station progressive, etc. In addition to stamping tonnage, considerations should also be given to punching times, feeding devices, machine tools, and mold protection devices.
6. The manufacturing methods and processes of the above-mentioned molds are not possessed and mastered by every enterprise. When choosing a collaborative manufacturer, it is important to understand its processing capabilities, not only based on hardware equipment, but also on management level, processing experience, and technical strength.
7. There may be significant differences in quotes from different manufacturers for the same set of molds. You should not pay more than the value of the mold, nor should you pay less than the cost of the mold. Mold manufacturers, like you, need to achieve reasonable profits in their business. Customizing a much lower priced mold would be the beginning of trouble. Users must start from their own requirements and comprehensively evaluate.
（3） Avoid multiple collaborations and try to make plastic molds and process products in one go.
1. With qualified molds (qualified specimens), it is not necessarily possible to produce a batch of qualified products. This is mainly related to the selection of machining tools for parts, forming processes (forming temperature, forming time, etc.), and the technical quality of operators.
2. With good molds, it is also necessary to have good forming and processing. It is best to collaborate in a one-stop manner and try to avoid multi head collaboration. If the conditions are not met, it is necessary to choose one party who is fully responsible, and it must be clearly stated during the contract.