Due to the concentration of processes and automatic tool change, the machining center reduces the time of workpiece clamping, measurement and machine tool adjustment, and the cutting time of the machine tool reaches about 80% of the starting time of the machine tool (common machine tools are only 15-20%); It also reduces the time of workpiece turnover, handling and storage between processes, shortens the production cycle, and has obvious economic effects. The machining center is suitable for small and medium-sized batch production with complex parts, high precision requirements, and frequent product replacement.

Since the 1970s, the machining center has developed rapidly. An interchangeable spindle box machining center has appeared. It is equipped with multiple multi-axis spindle boxes equipped with tools that can be automatically replaced, and can perform porous machining on the workpiece at the same time.

This form of multi-process centralized machining has also been extended to other types of CNC machine tools, such as turning centers. It is equipped with multiple automatic tool changers on a CNC lathe and can control more than three coordinates. In addition to turning, the spindle can be stopped Or indexing, and the process of milling, drilling, reaming and tapping by tool rotation is suitable for processing complex rotating body parts.

Machining centers are divided into vertical and horizontal types according to the arrangement of the spindle. The horizontal machining center generally has an indexing turntable or a numerical control turntable, which can process all sides of the workpiece; it can also be used for joint movement of multiple coordinates in order to process complex spatial curved surfaces. Vertical machining centers generally do not have a turntable, only for top surface machining. In addition, there are composite machining centers with vertical and horizontal spindles, and vertical and horizontal adjustable cnc machining centers with spindles that can be adjusted to horizontal or vertical axes. They can process five faces of the workpiece.