The internal clearance of a ball bearing for seated rolling bearings refers to the amount of movement (radial internal clearance) when one of the inner ring or the outer ring is fixed and the other is moved in the radial direction. The size of the internal clearance (called the working clearance) during operation has an impact on the bearing's rolling fatigue life, temperature rise, noise, vibration and other properties. When the bearing inner ring and the shaft are installed in interference, the expansion of the bearing inner ring must be considered to determine the internal clearance of the bearing. In addition, when the heat conduction to the shaft is high or the hollow hole of the shaft passes high-temperature steam, the reduction of the internal clearance must be calculated. Correctly select the internal clearance of the bearing (refer to 7 Operating temperature and bearing specifications). The applicable internal clearances of ball bearings for rolling bearings with seats are shown in Table 11.9, and the standard values u200bu200bof bearing internal clearances are shown in Table 11.10. Table 11.9 Applicable internal clearance of each specification of ball bearing for rolling bearing with seat. Applicable internal clearance. Note) For bearings with internal clearance in this table, the clearance symbol does not indicate. Cylindrical bore bearings, tapered bore bearings, ordinary products CN C3 for heat resistance (special symbol D1K2) C4 C5 for cold resistance (special symbol D2K2) CN C3 for high speed (special symbol K3) CN C3 for blower (special symbol S5) C2 C3 rolling bearing with seat Remarks for the standard value of the internal clearance of ball bearings) 1. The value of the radial internal clearance in this table is based on JIS B 1558 (Ball bearings for rolling bearings with housing). 2. The increase in radial internal clearance due to the measured load is shown in the table below. In addition, in the correction amount of C2 clearance, the smaller is suitable for the smallest clearance, and the larger is suitable for the maximum clearance.