(1) Large gate mold: the runner and gate are on the parting line, and demould together with the product when opening the mold. The design is the simplest, easy to process, and the cost is low. Therefore, many people use the large water gate system for operation.
(2) Fine nozzle mold: the runner and gate are not on the parting line, but directly on the product. Therefore, it is necessary to design an additional set of nozzle parting lines. The design is more complicated and the processing is more difficult. Generally, the fine nozzle system should be selected according to the product requirements.
（3） Hot runner mold: the structure of this kind of mold is roughly 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 pumps with constant temperature. There is no cold material demoulding. The runner and gate are directly on the product, so the runner does not need to be demoulded. This system is also known as no nozzle system, which can save raw materials and is suitable for situations where raw materials are expensive and product requirements are high, It is difficult to design and process, and the mold cost is high.
The so-called 2-plate mold generally refers to the large water mouth system mold, and the 3-plate mold generally refers to the water nozzle system mold. 3-plate die can not be simply considered as one more template than 2-plate mold. According to the product shape and mold design needs, the mold can have more than 3-plate knot
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 runner. Single point hot gate is to use a single hot gate sleeve to directly inject the molten plastic into the mold cavity, which is suitable for the plastic mold with single cavity and single gate; the multi-point hot gate is to branch the molten material into each sub Heat Gate sleeve and then into the cavity through the hot runner plate, which is suitable for single cavity multi-point feeding or multi cavity mold
Advantages of hot runner system
(1) No water mouth material, no need for post-processing, so that the entire molding process is fully automated, save working time and improve work efficiency.
(2) The pressure loss is small. The temperature of the hot runner is equal to that of the nozzle of the injection molding machine, which avoids the surface condensation of the raw materials in the runner and reduces the injection pressure loss.
(3) The reuse of nozzle material will degrade the properties of plastic, but the use of hot runner system without nozzle material can reduce the loss of raw materials and reduce the cost of products. In the mold cavity, the temperature and pressure are uniform, the stress of plastic parts is small, and the density is uniform. Under the small injection pressure and short molding time, the injection molding can produce better products than the general injection molding system. For transparent parts, thin parts, large plastic parts or high demand plastic parts, it can show its advantages, and can produce larger products with smaller machines.
(4) The hot nozzle adopts standardized and series design, equipped with various nozzle heads for selection, and has good interchangeability. The electric heating ring with unique design and processing can achieve uniform heating temperature and long service life. The hot runner system is equipped with hot runner plate, temperature controller, etc., with exquisite design, various types, convenient use, stable and reliable quality
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