In order to give full play to the original performance of the FYH rolling bearing with a house and maintain it for a long time, it is important to select a shaft suitable for the conditions of use. The shaft should be rigid enough to be free from bends, scratches, burrs, etc. The accuracy of the shaft: the dimensional tolerance of the shaft used in the cylindrical bore bearing with the set screw. The cylindrical bore bearing with the set screw uses a tolerance zone that can form a relatively loose fit for the sake of easy installation. The fit between the inner ring of the bearing and the shaft, the higher the speed of the bearing, the smaller the fit clearance should be. Table 9.1 shows the approximate standard of the tolerance band of the rotational speed of the cylindrical bore bearing with the set screw and the shaft used. Cylindrical bore bearings with set screws are under heavy load (Pr /Cr>0.12) and where there is vibration and impact, in order to prevent creep and peeling of the mating surface of the bearing inner ring and the shaft, the shaft used can be compared. Tight fit tolerance zone. Table 9.2 shows the approximate standard of the tolerance zone of the shaft to be used when forming a relatively tight fit with a cylindrical bore bearing with a set screw. In addition, the recommended values u200bu200bfor the roundness and cylindricity of the shaft are shown in Table 9.3. Dimensional tolerance of shaft used for cylindrical bore bearing with set screw (recommended) (for clearance fit or transition fit) Note) dnu003dd (bearing inner diameter, mm) n (rotation speed, min-1) Cylindrical with set screw Dimensional tolerance (recommended) of shafts used for bore bearings (in the case of transition fit or interference fit) Recommended accuracy of shafts used for rolling bearings with houses. Dimensional tolerance of shaft used in FYH blower bearing (cylindrical hole with set screw) Blower bearing (special symbol S5) operates at high speed and suppresses vibration and noise during operation. The clearance (C2) and the machining accuracy of the bearing have been improved by one level. Therefore, the recommended tolerance range shown in Table 9.4 is for the shaft used for the blower bearing (cylindrical hole with set screw). Dimensional tolerances of shafts used in bearings for blower (with set screw cylindrical holes) (recommended) Dimensional tolerances of shafts used in tapered bore bearings (with fasteners) Tapered bore bearings Use fasteners to fix the bearing to the shaft. Therefore, the shaft selected for ease of installation adopts a tolerance zone that can form a relatively loose fit. The dimensional tolerances for shafts used for tapered bore bearings (with fasteners) are shown in Table 9.5. Dimensional tolerances of shafts used for tapered bore bearings (with fasteners) (recommended) Dimensional tolerances of shafts used for cylindrical bore bearings with eccentric fixed rings FYH Cylindrical bore bearings with eccentric fixed rings If the fitting clearance is large, there is a danger that the shaft will be installed tilted. Therefore, it is recommended that the shaft used for the cylindrical bore bearing with eccentric retaining ring has the same tolerance band (h5 or j5) as the shaft used for the fan bearing (special symbol S5) (refer to Table 9.4). Dimensions of the stepped shaft: When using a cylindrical bore bearing in applications with a large axial load and severe vibration and shock, use a stepped shaft and fasten the inner ring of the bearing with a nut. The shoulder diameter of the stepped shaft and the fillet radius of the corner are shown in Table 9.6. Shoulder diameter of stepped shaft and corner radius (recommended).