There are two main techniques in the production process, namely, cold chamber die casting and hot chamber die casting. This section will primarily discuss the specific details of the hot chamber die casting process in the Eko industries. The hot chamber die casting technique uses alloys with low melting temperatures such as magnesium and zinc to produce high precision die cast products. The process involved with hot chamber die casting does not accommodate alloys with high melting temperatures as this damages the critical components of the machine, including the nozzle and the gooseneck.
The hot chamber die casting process
Here are some of the parts directly involved with the process;
- Gooseneck passage
- Plunger rod
- Shot cylinder
- Intake port
- Hot chamber
There is one characteristic of the die casting process: the use of increased pressure to force the molten metal through the die. Most of the main features of castings produced through die casting are attributed to high pressure to ensure that the metal flows easily through the die. In the hot chamber die casting process, the supply of the molten metal is bound to the die casting machine. This is the central part of the casting components for this process.
At the beginning of the process, the shot cylinder provides the power for the injection stroke. The short cylinder is found above the supply of the molten metal. The plunger rod moves from the shot cylinder to the plunger, which is in contact with the molten material. At the beginning of the casting process, the plunger is usually at the hot chamber’s top. The intake ports help this chamber to take in the liquid metal.
Also, once the power cylinder forces the plunger down, this plunger moves past the past slowing down the flow of liquid metal to the hot chamber. This results in enough molten material collecting in the chamber ready to be shot and produce the casting.
At this point, the plunger continues traveling downwards, thus forcing the molten liquid into the die. The pressure that is exerted by the plunger to the liquid metal varies from 700psi to 5000psi. This force is exerted for a long time to ensure that the casting has solidified.
As a preparation for the next hot chamber die casting process, the plunger travels back to the upward part of the hot chamber. It exposes the intake ports and allows the chamber to refill with the molten material. You can find more details about the process through this link; https://www.ekoindustries.com/precision-die-casting/hot-chamber-die-casting/.
Hot chamber die casting, unlike cold chamber die casting, is more advantageous because it leads to the high production rate of solid casting. During the industrial manufacture using this process, one of the disadvantages experienced is that the setup requires that the most critical components of the apparatus, such as the plunger, are continuously submerged in the molten material. If submersion continues, it causes thermal-related damages to the component due to the high temperatures. As a result, the functionality of these parts is impaired. For this reason, this method makes use of lower melting point alloys such as tin, lead, and zinc to manufacture metal castings.
Main Photo by Jakub Skafiriak.