Depending on demand, each bearing manufacturers provide different accuracy requirements, the following will be some of the bearings
Accuracy class introduced
The rolling bearing precision divided into: dimensional accuracy and rotational accuracy.
Bearing accuracy class standards for the 0, 6X, 6, 5, 4, 2 six levels.
Bearing accuracy improve sequentially starting from 0, is sufficient for the average 0, but for other conditions or occasions when
Need 5 or higher accuracy.
The above accuracy rating based on ISO standards for benchmarking, but its call to different national standards
The dimensional accuracy of the bearing (installed with the shaft and housing related projects)
1, an inner diameter, an outer diameter, width, and fitted with the width of the allowable deviation
2, a group of roller diameter and the diameter of the outer umbra umbra allowable deviation
3, the acceptable limit of chamfer dimension value
4, the width of the allowable fluctuation amount
The accuracy of rotation of the bearing (beating with the rotating body related projects)
1, the inner ring and outer ring radial runout and axial runout
2, the inner ring to allow lateral runout
3, the outer diameter surface to allow changes in the amount of inclination
4, the thrust of the thickness of the bearing raceways allow fluctuation amount
5 allowable deviation of the tapered bore and allows changes in the amount of
Most cases the application the general dimensional accuracy and rotational accuracy of the bearing (tolerance grade PN) is sufficient. When the requirements are higher, the bearings need a higher level of accuracy, for example, such as machine tool spindle bearings. In order to achieve higher accuracy requirements, the standard specifies the the P6, P6X, P5, P4 and P2 tolerance level. P4S, SP and UP tolerance level for some special bearing requirements in accordance with company standards.
Wrong neutral processing journalled mating surface or bearing mating surface, especially when the mating surfaces of the processing is not a loaded card. The chock will produce misalignment, such as flange bearing or vertical bearing. The axis bending deformation due to the work load, also occur and cause the bearing inner and outer rings tilt misalignment.


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