Everything You Need to Know About High-pressure Die Casting

Forced into a securely locked metal die cavity, Aluminum high pressure die casting is a process in which under pressure molten metal is where until the metal solidifies and it is held by a powerful press. After the completion of metal solidification, the die is unlocked, opened, and the casting is ejected. After the removal of casting, for the next cycle, the die is again closed and locked. In a fraction of a second, the injection of metal into the die cavity is completed. Extremely high pressure is applied when the molten metal is still held in the die, which is referred to as intensification pressure.

In the process of aluminum high pressure die casting china, for injecting the molten metal into the die two types of systems are used. With metals such as zinc, magnesium, and lead the hot chamber system is used. In a hot chamber machine, the injection system is immersed in the molten metal bath of the melting furnace. By the movement of the shot plunger, the metal is forced through the nozzle and into the die.

For metals that melt at high temperatures, such as magnesium, aluminum, and brass the cold chamber system is used. Using both systems even magnesium parts can be produced, however, small parts are produced in hot chamber machines and large parts in cold chamber machines because hot chamber machines are restricted in size. In the cold chamber process, there are two injection systems used, horizontal and vertical injection. In the aluminum high pressure die casting process of a cold chamber, by hand or by automatic means the molten metal is poured into a port of the cold chamber sleeve.

Through this steel sleeve, a hydraulically operated plunger starts advancing, resulting in sealing off the port, and forcing the metal into the die at high speed and pressure. The plunger is retracted, the die opened, the casting ejected after solidification of the casting is done, and for the next shot cycle, the system is then ready. Compared to a cold chamber machine the production rate of a hot chamber machine is higher as a shorter time is needed during the pour operation.