The internal clearance of a ball bearing for FYH rolling bearing housing refers to the amount of movement (radial internal clearance) when one of the inner or outer rings is fixed and the other moves radially. The size of the internal clearance (called working clearance) during operation has an impact on the rolling fatigue life, temperature rise, noise, vibration and other properties of the bearing. When the bearing inner ring and the shaft are installed with 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 high temperature steam passes through the hollow hole of the shaft, 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). Table 11.9 shows the applicable internal clearance of each specification of ball bearings for FYH rolling bearings with a block, and table 11.10 shows the standard values u200bu200bof the bearing internal clearance. Table 11.9 Applicable Internal Clearance for Each Specification of Ball Bearings with Housings Specifications Applicable Internal Clearance Note) For bearings that are applicable to the internal clearances in this table, the clearance symbols are not indicated. FYH Cylindrical Bore Bearing Tapered Bore Bearing Common Product CN C3 For Heat Resistance (Special Symbol D1K2) C4 C5 For Cold Resistance (Special Symbol D2K2) CN C3 For High Speed u200bu200b(Special Symbol K3) CN C3 For Blower (Special Symbol S5) C2 C3 With Seat Remarks for the standard value of internal clearance of ball bearings for rolling bearings) 1. The values u200bu200bof radial internal clearance in this table are based on JIS B 1558 (ball bearings for rolling bearings with a house). 2. The increase in radial internal clearance due to the measured load is shown in the table below. In addition, among the correction amounts of C2 clearance, the smaller one applies to the minimum clearance, and the larger one applies to the maximum clearance.