Molten metals have to be cooled down in a mold to form products. A gravity casting machine simply uses the force of gravity to flow the molten metal into the correct molds. A large variety of complex shaped castings (final products) can be made this way. Other casting processes exist, with gravity casting having the best overall metrics. Aside from the versatility of the castings made, the other processes have obvious limitations. Gravity casting has few pieces of equipment, low production costs, and dimensional accuracy of finished products. Because of this, it has arguably the best overall metrics in the metal casting niche of the industry. These are the measurements we will look into: structures, principles and characteristics, new applications, foresight and developmental tendencies of gravity casting machines.
How Gravity Casting Machines Work？
The main function of a gravity casting machine is using gravity to guide molten metal into a machine prepared mold where the metal cools and solidifies. The four main steps in the process is how gravity casting machines work.
1.Mold Preparation Before casting,
the mold is preheated and a release agent is applied to the mold. This is done to avoid defects that come due to the cooling of metal in the mold.
2.Metal Melting
The metal or metal alloy that is to be used, is heated once again but this time it is taken to a temperature high enough to make it a liquid. This is done by using either an induction furnace or a resistance furnace.
3.Pouring of Molten Meta
The mold is filled with the molten metal, through a gating system. Metal is poured into the mold using only gravity and nothing else. This is done unlike in pressure casting where there is use of external pressure to fill the mold.
4.Cooling and Solidification
Once the metal cools enough to be a solid, the mold is removed.
5.Casting Removal
Once the casting is cool enough to be handled it is blanked and can go through other post processing steps like polishing, cutting, and/or heat treatment.