What Is The Principle of Low Pressure Casting?

Low-pressure casting is a casting method in which a liquid alloy is pressed into a mold cavity from bottom to top under the action of pressure, and solidified under the action of pressure.

The principle of low-pressure casting is that dry compressed air or inert gas is passed into the sealed crucible, and the metal liquid is smoothly filled from the bottom to the top along the riser pipe through the runner by virtue of the pressure on the liquid surface. , The filling pressure is generally 20 ~ 60kPa. When the casting is completely solidified, the gas pressure on the liquid surface is released, so that the metal liquid that has not solidified in the riser pipe and the runner flows into the crucible by its own weight, and then the mold is opened and the casting is removed.

The production process of low pressure casting includes the following four basic procedures:

1. Metal smelting and mold or mold preparation.

2. Preparation before pouring: including crucible sealing, slag pick-up in the riser, measuring liquid level, sealing test, mold matching, tightening mold or casting mold, etc.

3. Pouring: including liquid raising, filling, pressurization, solidification, pressure relief and cooling.

4. Demoulding: Including loose demoulding and taking out castings.

The above is the principle of low-pressure casting and its production process. During the casting process, the staff must perform the normal operation to ensure personal safety.