Improved Precision
After the bearing is installed in the main machine, measuring the radial runout of the spindle reveals a certain change in value with each revolution. Continuous measurements show that this change approximately repeats itself after a certain number of revolutions. The indicator of this degree of change is cyclic rotational accuracy. The number of revolutions required for the change to approximately repeat represents the "quasi-period" of the cyclic rotational accuracy. A large amplitude of change within the quasi-period indicates poor cyclic rotational accuracy. Applying appropriate preload to the spindle and gradually increasing the speed to near the operating speed to achieve a "run-in" effect on the bearing can improve the spindle's cyclic rotational accuracy.
Installation of Tapered Bore Double-Row Short Cylindrical Roller Bearings
When installing NN3000K series tapered bore double-row short cylindrical roller bearings, it is crucial to ensure a correct fit between the bearing's inner diameter and the shaft's taper. For small production runs, a color-coding method can be used for contact calibration. However, for larger production runs, it is best to use a precision taper gauge for calibration. When installing the bearing onto the tapered shaft, the inner ring should be adjusted axially to the appropriate position so that its radial clearance is close to zero.