The lathe spindle refers to the axis on the machine tool that drives the rotation of the workpiece or tool. Usually composed of spindle components, bearings, and transmission components (gears or pulleys). In machines, it is mainly used to support transmission components such as gears and pulleys, transmit motion and torque, such as lathe spindles; Some are used to clamp workpieces, such as mandrels. Except for machine tools such as planers and pullers whose main motion is linear, most machine tools have spindle components. The motion accuracy and structural stiffness of the spindle components are important factors determining machining quality and cutting efficiency.

The main indicators for measuring the performance of lathe spindle components are rotational accuracy, stiffness, and speed adaptability.

① Rotation accuracy: The radial and axial runout that occurs in the direction that affects machining accuracy during spindle rotation is mainly determined by the manufacturing and assembly quality of the spindle and bearings.

② Dynamic and static stiffness: mainly determined by the bending stiffness of the spindle, the stiffness and damping of the bearings.

③ Speed adaptability: The allowable high speed and speed range are mainly determined by the structure and lubrication of the bearings, as well as the heat dissipation conditions