What Is Bearing Tolerance Class?
Bearing tolerance class defines the manufacturing precision of a bearing per ISO 492. It specifies allowable deviations in bore diameter, outer diameter, width, and running accuracy (radial and axial runout). Classes range from Normal (P0) to ultra-precision (P2).
Tolerance Classes
| ISO Class | ABEC Equiv. | Application |
|---|---|---|
| P0 (Normal) | ABEC 1 | General industrial |
| P6 | ABEC 3 | Machine tools, electric motors |
| P5 | ABEC 5 | High-speed spindles |
| P4 | ABEC 7 | Precision grinding spindles |
| P2 | ABEC 9 | Gyroscopes, metrology |
Frequently Asked Questions
What is the difference between P0, P6, and P5 bearing tolerance?
P0 (Normal) is the standard manufacturing tolerance for general applications. P6 offers tighter dimensional and running accuracy -- used in machine tools and precision equipment. P5 is even more precise, used in high-speed spindles. P4 and P2 are ultra-precision for aerospace and metrology.
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