Casting can be divided into gravity casting and pressure casting according to the casting process of metal liquid.Gravity casting refers to the process of injecting metal liquid into casting under the action of earth's gravity, also known as casting.

Gravity casting in a broad sense includes sand casting, metal casting, investment casting, disappearing mold casting, mud mold casting, etc.; gravity casting in a narrow sense specifically refers to metal casting.Pressure casting refers to the external force of liquid metal in other (No gravity )The process of injecting casting under action.Pressure casting in a broad sense includes pressure casting and vacuum casting, low-pressure casting, centrifugal casting, etc. of die-casting in a narrow sense refers specifically to metal-type pressure casting of die-casting machines, referred to as die-casting.Precision casting factory has been engaged in gravity casting of sand and metal forms for a long time.These casting processes are commonly used in non-ferrous metal casting and are of relative price.

Die casting is a metal-type pressure casting performed on a die-casting machine, and is a casting process with current production efficiency.Die-casting machines are divided into two categories: hot chamber die-casting machines and cold chamber die-casting machines.The hot chamber die casting machine has a high degree of automation, less material loss, and has higher production efficiency than that of the cold chamber die casting machine. However, due to the heat resistance of the machine parts, it can only be used for castings with low melting point materials such as zinc alloys and magnesium alloys.The widely used aluminum alloy die-casting parts today can only be produced on cold room die-casting machines due to their high melting point.The main feature of die casting is that metal liquid fills the cavity at high pressure and high speed, and forms and solidifies under high pressure. The disadvantage of die castings is that because the metal liquid fills the cavity at high pressure and high speed, the air in the cavity is inevitably wrapped inside the casting to form subcutaneous air holes, so aluminum alloy die castings are not suitable for heat treatment, and zinc alloy die castings are not suitable for surface spraying. (But can be sprayed )。Otherwise, when the internal air holes of the casting are heated by heating the above treatment, the casting will be deformed or bubbled due to heat expansion.In addition, the mechanical cutting allowance of die castings should also be smaller, generally at 0.5 mm Left and right, it can not only reduce the weight of castings, reduce the amount of cutting and processing to reduce costs, but also avoid penetration of the dense surface layer, exposing the subcutaneous pores, causing the workpiece to be scrapped.