Machining is a process of changing the dimensions or properties of a workpiece with a machining machine. According to the temperature state of the workpiece to be processed, it is divided into cold working and hot working. It is generally processed at room temperature and does not cause chemical or phase changes in the workpiece, which is called cold processing. Generally, processing above or below normal temperature will cause chemical or phase changes in the workpiece, which is called hot processing. Cold working can be divided into cutting and pressure working according to the difference in processing methods. Thermal processing commonly includes heat treatment, forging, casting and welding. In addition, cold heat treatment is often used during assembly. For example, when the bearing is assembled, the inner ring is often cooled in liquid nitrogen to shrink its size, and the outer ring is properly heated to enlarge its size, and then assembled together. The outer ring of the wheel of the train is also set on the substrate by heating, and the firmness of its combination can be ensured when it is cooled.
Machining includes: filament power winding, laser cutting, heavy duty machining, metal bonding, metal drawing, plasma cutting, precision welding, roll forming, sheet metal bending, die forging, water jet cutting, precision welding, etc.
Machining: In a broad sense, machining is the process of making products by mechanical means; in a narrow sense, it is the process of making parts with special mechanical equipment such as lathes, milling machines, drilling machines, grinders, punching machines, and die-casting machines.