The characteristics of gas assisted injection molding and injection molding are that the general injection molding method requires the wall thickness of the plastic part to be as uniform as possible, otherwise defects such as shrinkage holes and depressions may occur at the wall thickness. For thick wall crabs, Dongguan Machike Injection Molding Plant needs to strengthen the pressure maintaining and feeding time in order to prevent depression. However, if the thick wall is far away from the gate, even if the pressure is excessively maintained, it is often difficult to work. At the same time, due to excessive pressure retention near the gate, residual stress increases, which can easily cause warping, deformation, or cracking of the crab parts. Foreign countries have adopted a new process of gas assisted injection molding, which effectively solves the injection molding problems of plastic parts with uneven wall thickness and hollow shells. In addition, gas assisted injection molding has other characteristics. At present, the new process of gas assisted injection molding and injection molding is gradually being promoted and applied.

1、 The principle of gas assisted injection molding

The principle of gas assisted injection molding is relatively simple. During the injection filling process, a gas with lower pressure compared to the injection pressure is injected into the melt, usually several to several tens of megapascals. The gas pressure is used to achieve pressure maintaining and contraction. The principle of gas assisted injection molding. The principle of gas assisted injection molding is that gas enters the plastic melt from inside. During molding, accurately measured melt is first injected into the mold cavity, and then gas is injected into the melt through a special nozzle. Gas diffusion drives the melt to fill the mold cavity. After the filling of the mold is completed, the pressure of the gas in the melt remains unchanged or increases to maintain pressure and replenish the material. After cooling, the gas inside the plastic part can be removed and the mold can be demolded. Gas pressure forming method on the surface of plastic melt, also known as surface gas forming method. This method is a method of injecting high-pressure gas into the specially closed area of the bottom surface of the plastic injection molded product inside the mold, so that the surface of the injection molded product is free of shrinkage marks.

The characteristic of gas assisted injection molding is that this special closed area can also be referred to as the pressure zone, and each pressure zone is surrounded by sealing components connecting the finished product to prevent gas leakage. The cross-section of the sealing components can be rectangular or triangular, which can enhance the rigidity of the finished product. Of course, the surface gas molding method adopted by Dongguan Machike Injection Molding Plant will leave obvious marks in the pressurized area, but it will never affect the surface of injection molding products. The surface gas forming method is particularly suitable for the following situations:; When the shrinkage rate of plastic is very high; When the back of cylindrical objects in injection molded products is prone to dents; The process of melt filling the mold cavity is very long; When the finished product is thin-walled and irregular, and cannot be filled with air pockets or thick walls. In gas assisted injection molding, the quantification of melt is very important. If too much melt is injected, it will cause uneven wall thickness; On the contrary, if too little melt is injected, the gas will break through the melt and make the molding impossible.

2、 Classification and Process of Gas Assisted Injection Molding

The characteristics of gas assisted injection molding are that gas assisted injection molding can be achieved by adding a set of gas supply devices to existing injection machines. According to the usage abroad, gas assisted injection molding can be divided into standard molding method, melt reflux molding method, and movable core exit method.

Dongguan Qianglian Machinery Casting Co., Ltd. is a wholly-owned Taiwanese enterprise. In 2001, our equipment operation company adheres to the business philosophy of "customers are our life quality is our mission" and "integrity". The products are sold domestically and exported to countries and regions such as Japan, Taiwan, and Europe. The company covers a total area of 50000 square meters, with a factory building area of 30000 square meters.

Production capacity: Annual production capacity 26000 tons, with a maximum casting capacity of 45 tons per piece.

Main products: Mechanical casting, such as automotive molds, punches, machining centers, gantry milling machines, injection molding machines.

Exclusive: nodular cast iron FCD40-70, Gray iron FC25-35, automobile mold GM246241.