Equipment for die-casting
2023-06-08
Die casting machines can be mainly divided into two different types: hot chamber die casting machines and cold chamber die casting machines. The difference lies in how much force they can withstand, with a typical pressure range of 400 to 4000 tons.
Hot chamber die casting
Hot chamber die casting, sometimes also known as goose neck die casting, has a molten state of liquid or semi liquid metal in its metal pool, which fills the mold under pressure. At the beginning of the cycle, the piston of the machine is in a contracted state, and the molten metal can fill the gooseneck area. Air pressure or hydraulic piston compresses metal and fills it into the mold. The advantages of this system include fast cycle speed (about 15 cycles can be completed per minute), easy automation, and convenient melting of metals. Disadvantages include the inability to die cast metals with higher melting points, as well as the inability to die cast aluminum, as aluminum can remove iron from the melting pool. Therefore, hot chamber die-casting machines are usually used for alloys of zinc, tin, and lead. Moreover, hot chamber die casting is difficult to use for large castings, and usually this process involves small castings.
Cold chamber die casting
When die casting cannot be used for metals in hot chamber die casting processes, cold chamber die casting can be used, including aluminum, magnesium, copper, and zinc alloys with higher aluminum content. In this process, the metal needs to be melted first in an independent crucible. Then a certain amount of molten metal is transferred to an unheated injection chamber or injection nozzle. These metals are injected into the mold through hydraulic or mechanical pressure. The disadvantage of this process is that it takes a long cycle time due to the need to transfer molten metal into the cold chamber. Cold chamber die-casting machines can be divided into vertical and horizontal types. Vertical die-casting machines are usually small machines, while horizontal die-casting machines come in various models.
