Mold is one of the important basic process equipment in the manufacturing industry. A mold is formed from raw materials in a certain way based on its specific shape. The high precision, high consistency, high productivity, low energy consumption, and low consumables achieved by mold production make the mold industry increasingly important in the manufacturing industry.

When choosing a plastic mold processing enterprise, the first step is to choose based on the mold being processed. Generally speaking, machines with high accuracy, multiple curved surfaces, and high speed light cutting should be selected. In addition to considering these factors, their cost-effectiveness also needs to be considered.

The various tools and products we use in our daily production and daily life, ranging from the base of machine tools and the outer shell of the machine body to a small screw, button, and the outer shell of various household appliances, are all closely related to molds. The shape of the mold determines the appearance of these products, and the processing quality and accuracy of the mold also determine the quality of these products. Due to the different materials, appearances, specifications, and uses of various products, molds are divided into non plastic molds such as casting molds, forging molds, die-casting molds, stamping molds, and plastic molds.

In recent years, with the rapid development of Dongguan Plastic Mold Factory and the continuous improvement of strength and precision in general and engineering plastics, the application scope of Dongguan Plastic Mold Factory has also been expanding, such as in many fields such as household appliances, instruments and meters, construction equipment, automotive industry, daily hardware, etc. The proportion of plastic products is rapidly increasing. A well-designed plastic component can often replace multiple traditional metal components. The trend of plasticization of industrial and daily products is constantly increasing.

meaning

The general definition of molds in Dongguan Plastic Mold Factory: In industrial production, various presses and specialized tools installed on the press are used to produce metal or non-metallic materials into the required shape of parts or products through pressure. These specialized tools are collectively referred to as molds.

Injection molding process description: A mold is a tool for producing plastic products. It consists of several sets of parts, with a forming cavity inside this combination. During injection molding, the mold is clamped onto the injection molding machine, and the molten plastic is injected into the mold cavity, cooled and shaped inside the cavity. Then, the upper and lower molds are separated, and the product is ejected from the mold cavity through the ejection system. Finally, the mold is closed for the next injection molding, and the entire injection process is cyclic.

classification

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 - bakelite switch, scientific ceramic bowl and dish

D. Transfer Forming Mold - Integrated Circuit Products

E. Extrusion molding mold - glue pipes, plastic bags

F. Thermoforming mould - transparent forming packaging shell

G. Rotary Forming Mold - Soft Adhesive Doll Toys

According to the different types of pouring systems, molds can be divided into three categories:

(1) Large water outlet mold: The runner and gate are on the parting line and demoulded together with the product during mold opening. The design is the simplest, easy to process, and the cost is lower, so many people use the large water outlet system for operation.

(2) Fine nozzle mold: The runner and gate are not on the parting line, usually directly on the product. Therefore, it is necessary to design an additional set of nozzle parting lines, which is more complex in design and difficult to process. Generally, the selection of a fine nozzle system depends on the product requirements.

(3) Hot runner mould: the structure of this kind of mould is basically the same as that of the fine nozzle. The biggest difference is that the runner is located in one or more Hot runner plates and hot pump mouths with constant temperature, and there is no cold material demoulding. The runner and gate are directly on the product, so the runner does not need demoulding. This system is also called the nozzle free system, which can save raw materials. It is suitable for situations where raw materials are expensive and product requirements are high, and it is difficult to design and process, The mold cost is relatively high.

Hot runner system, also known as hot runner system, is mainly composed of hot runner sleeve, hot runner plate and temperature control electric box. Our common Hot runner system has two forms: single point hot gate and multi-point hot gate. Single point hot gate is a plastic mold that uses a single hot gate sleeve to directly inject molten plastic into the mold cavity. It is suitable for single cavity and single gate plastic molds; Multi point hot gate is a method of branching molten material into each sub hot gate sleeve through a hot gate plate and entering the mold cavity. It is suitable for single cavity multi point feeding or multi cavity molds

◆ Advantages of Hot runner system

(1) Waterless mouth material, no need for post processing, fully automated the entire molding process, saving work time and improving work efficiency.

(2) Low pressure loss. The temperature of the hot runner is equal to the nozzle temperature of the injection molding machine, which avoids the surface condensation of raw materials in the runner and reduces the loss of injection pressure.

(3) Reuse of nozzle material will degrade the plastic performance, while the use of Hot runner system without nozzle material can reduce the loss of raw materials, thus reducing the product cost. In the mold cavity, the temperature and pressure are uniform, the plastic stress is small, and the density is uniform. Under lower injection pressure and shorter molding time, injection molding produces better products than general injection molding systems. For transparent parts, thin parts, large plastic parts, or high demand plastic parts, their advantages can be better demonstrated, and larger products can be produced using smaller models.

(4) The hot nozzle adopts a standardized and serialized design, equipped with various nozzle heads to choose from, and has good interchangeability. The uniquely designed and processed electric heating ring can achieve uniform heating temperature and long service life. The Hot runner system is equipped with Hot runner plates, temperature controllers, etc., which are exquisite in design, diverse in types, convenient in use, stable and reliable in quality.

◆ Shortcomings of Hot runner system application

(1) The overall height of the mold closure has increased due to the installation of hot runner plates, etc., resulting in an increase in the overall height of the mold.

(2) The heat radiation is difficult to control, and the biggest problem with hot runners is the heat loss of the runners, which is a major issue that needs to be addressed.

(3) There is thermal expansion, and Thermal expansion are problems we should consider when designing.

(4) The increase in mold manufacturing costs and the high price of standard accessories for hot runner systems have affected the popularity of hot runner molds.