Gravity Casting

一、What is Gravity Casting

Gravity casting, formally known as gravity metal mold casting, is a traditional casting process that utilizes Earth's gravitational force to naturally fill molten metal into pre-made mold cavities. After the molten metal cools and solidifies, the castings are removed. Its core characteristic is the absence of external forces (such as pressure or centrifugal force), relying solely on the metal's own weight for filling. It stands as one of the most widely applied and technically mature processes in the foundry industry.

二、Core Principles of Gravity Casting

Metal Melting: Heating raw metal materials (such as aluminum alloys, cast iron, copper alloys, etc.) above their melting points to produce liquid metal meeting specified composition requirements.

Gravity Filling: Slowly pour the molten metal through the sprue (pouring channel) into the cavity of a pre-made mold (typically metal molds, occasionally sand molds). Under its own gravity (approximately 9.8 N/kg), the molten metal flows naturally and fills every detail of the mold cavity;

Cooling and solidification: After the molten metal fully cools and solidifies within the mold cavity, the mold is opened to remove the formed casting. Subsequent cleaning (such as removing gates and risers, deburring) and machining processes are performed to obtain the final product.