The electrical spindle can be categorized by the type of bearing used, including rolling bearings, air-bearing, liquid lubricated bearings, and magnetic levitation bearings. Among them, rolling bearings, air-bearing, and liquid lubricated bearings are the most widely used bearing types in electrical spindles.

The rolling bearing spindle boasts its wide applications due to its low friction resistance, low power consumption, high precision, high rigidity, and relatively low cost, commonly used in CNC engraving and milling machines, PCB forming machines, machining centers, CNC milling machines, lathes, and internal grinding. The air floating bearing spindle, supported by an "air film," features a compact structure, smaller size, higher rotational precision and maximum speed, lower friction loss than rolling bearing spindles and liquid sliding bearing spindles, lower noise, good thermal stability, minimal pollution, and longer lifespan, primarily applied in high-precision, high-speed, and light-load machining fields. The liquid sliding bearing spindle, supported by a "liquid oil film," exhibits significant "error averaging effect" and damping vibration characteristics, high rotational precision, high rigidity, low wear, and long lifespan, mainly used in heavy-duty, high-power machining and precision or ultra-precision machine tools. The magnetic suspension bearing spindle has a high maximum speed, operates without contact, friction, or loss, with a long lifespan, automatically balances during rotation, and requires no lubrication or sealing for vibration-free operation, enabling real-time diagnosis and online monitoring, primarily applied in ultra-high-speed machining fields.