Low-pressure casting is a process technology in which molten metal fills the mold cavity from bottom to top under the action of low pressure (20-60kPa), and solidifies to form castings. It has the characteristics of stable filling, good casting formability, and dense structure. The quality and yield of castings have the incomparable advantages of sand casting and gravity casting, which can meet the quality standards necessary for high-end large products. The brass casting equipment and technology introduced by the company, the casting process adopts PLC control, which has high automation and production efficiency, low labor intensity, energy saving, and less environmental pollution.