Tolerances for Radial Ball Bearings, include (but are not limited to) dimensional and running accuracy and are regulated by standards such as DIN, ABEC, ISO, and JIS B1514 to ensure manufacturing uniformity.
These standards specify tolerance and permissible dimension values like bore diameter, outside diameter, width, chamfer, taper, and more. They also provide variation limits on bore, mean bore, outside diameter, mean outside diameter, ring width, etc. to establish machining accuracy.
These accuracy measurements are defined as Precision Bearing Runout(s). Runout measurements are what define the rotational accuracy of the bearing.
Bearing runout tolerances are included in the standards for inner and outer ring, radial & axial runout, inner ring side runout with bore and outer ring surface runout with side.
Below are tables outlining the Internal Clearance options and tolerances of those internal clearances for Radial Ball Bearings.
What is Internal Clearance for a Bearing?
Internal Clearance is the amount the balls can move relative to the raceways, when in a free state.
To calculate the internal clearance for a radial ball bearing, you need to combine the internal clearance choices with installation clearances (or press fits of mating parts).
These tables below should give you a good idea on internal clearances for a radial ball bearing. But feel free to contact us for any questions you may have.
Standard Bearing Tolerance Classes & Equivalents
| Standards Group Name | Tolerance Classes & Equivalents | ||||
|---|---|---|---|---|---|
| Annular Bearings Engineers Committee (ABEC) | ABEC 1 | ABEC 3 | ABEC 5 (Class 5P) | ABEC 7 (Class 7P) | ABEC 9 (Class 9P) |
| International Organization for Standardization (ISO 492) | Class Normal | Class 6 | Class 5 | Class 4 | Class 2 |
| Deutsche Industrie Norm (DIN) | P 0 | P 6 | P 5 | P 4 | P 2 |
| Japanese Industrial Standards (JIS) | Class 0 | Class 6 | Class 5 | Class 4 | Class 2 |
| Nominal Bore Diameter (d) (mm) | Clearance | |||||
|---|---|---|---|---|---|---|
| C2 | Normal | C3 | C4 | C5 | ||
| over | incl | min - max | min - max | min - max | min - max | min - max |
| 10 only | - | 0-7 | 2-13 | 8-23 | 14-29 | 20-37 |
| 10 | 18 | 0-9 | 3-18 | 11-25 | 18-33 | 25-45 |
| 18 | 24 | 0-10 | 5-20 | 13-28 | 20-36 | 28-48 |
| 24 | 30 | 1-11 | 5-20 | 13-28 | 23-41 | 30-53 |
| 30 | 40 | 1-11 | 6-20 | 15-33 | 28-46 | 40-64 |
| 40 | 50 | 1-11 | 6-23 | 18-36 | 30-51 | 45-73 |
Clearances for Small & Miniature Bearings
| Clearance Mark | MC1 | MC2 | MC3 | MC4 | MC5 | MC6 |
|---|---|---|---|---|---|---|
| Clearance | min - max | min - max | min - max | min - max | min - max | min - max |
| 0-5 | 3-8 | 5-10 | 8-13 | 13-20 | 20-28 |
Units: µm
Clearances for Electric Motors
| Nominal Bore Dia. d (mm) | Clearance CM |
|---|---|
| over-incl | min - max |
| 10 (inch) -18 | 4-11 |
| 18-30 | 5-12 |
| 30-50 | 9-17 |
Please contact one of our onsite engineers if you have any questions or need help calculating your radial ball bearing clearance and tolerance.