Spindle Rotational Accuracy Test

Spindle rotational accuracy is a critical performance metric that reflects the stability and machining precision of a spindle. It is measured by the radial runout and axial movement of the spindle nose or tooling interface under low-speed, no-load conditions. This accuracy depends heavily on the manufacturing quality and assembly precision of spindle components.

Common industry standards for spindle accuracy include:

• A Spindle inner taper runout ≤ 2μm
• B Spindle nose face runout ≤ 1μm
• C 300mm test bar runout ≤ 15μm

Precise rotational accuracy improves surface finish, reduces tool wear, and ensures long-term spindle stability. Measurement points are illustrated in Fig. 1.

Fig. 1 Spindle Accuracy Test Diagram

Dynamic Spindle Accuracy

Dynamic spindle accuracy refers to the positional stability, speed consistency, and motion precision of a spindle during operation. In high-precision machining applications, dynamic accuracy plays a crucial role in achieving tight tolerances, consistent surface finishes, and superior part quality. A spindle with excellent dynamic performance minimizes vibration and dimensional errors, boosting overall process reliability, product yield, and machine life.