systems originated from the non runner system in the injection molding industry. As an advanced plastic injection molding technology, its popularity in western developed countries can be traced back to the middle of last century or even earlier.
Hot runner system has many advantages, and it has developed rapidly in foreign countries. More than 50% of the moulds produced by many plastic mould factories adopt hot runner technology, and some of them even reach more than 80%. In China, this technology has been fully promoted and applied in the past decade. With the continuous development of the mold industry, the proportion of hot runner used in plastic mold has gradually increased, but on the whole, it has not reached the proportion of foreign hot runner mold.
In order to catch up with the western developed countries in China's hot runner technology as soon as possible, the small braided horse shouldering the heavy responsibility comes to popularize the relevant knowledge of hot runner system for you!
- for hot runner systems -
Hot runner, that is, by heating to ensure that the runner and gate of the plastic to maintain a molten state.
The hot runner system is generally composed of hot nozzle, distributor, temperature control box and accessories.
There are two kinds of hot nozzle: open hot nozzle and needle valve hot nozzle. The hot runner system is usually divided into open hot runner system and needle valve hot runner system because the hot nozzle form directly determines the selection of hot runner system and the manufacture of mold.
- advantages of hot runner system -
1. There is no need for post-processing, so that the whole molding process is fully automated, saving working time and improving work efficiency.
2. Low pressure loss. 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 repeated use of nozzle material will degrade the properties of plastic, while 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. It can be used to produce large and thin plastic parts.
4. The hot nozzle adopts the standardized and series design, equipped with various nozzle heads for selection, with 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.
- hot runner application case study -
The material is PE, the weight of the product is 0.46g, and the number of cavities is 64. Customers have color change requirements. The surface of the product is the appearance surface, which can not be glued. Therefore, the glue feeding point is on the side wall of the product. The traditional hot nozzle can not meet the needs of customers.
Hot runner scheme
The hot runner system is one outlet 64 all hot side gate;
Heat dissipation and support column holes are added to the splitter plate;
The structure of hot nozzle is one outlet four side gate.
The hot runner adopts front-end disassembly, which can avoid repeated disassembly and assembly of formwork in subsequent maintenance
Mass production sample
The gate has perfect glue breaking, no wire drawing and no residual glue;
64 cavity balance ratio control OK;
Injection pressure 85bar, within the target set by the customer;
The color change is OK, the product has no surface impurities and color spots.
After reading the above dry goods, do you have any new ideas about the hot runner system?
Is the injection molding person in front of the screen thinking of trying the hot runner system?
In recent years, hot runner technology has been gradually popularized in China, which is largely due to the rapid increase in the export volume of molds from China to European and American companies. In Europe and the United States, injection molding production has been dependent on hot runner technology. In other words, the mold without hot runner technology is now difficult to export, which has caused many mold manufacturers to change their awareness of hot runner technology.