7224 BM /DB bearing
120 × 215 mm · dynamic rating 267.3 kN · static rating 326 kN. Dimensions, load ratings, designation meaning, life estimates and equivalent parts.
7224 BM /DB specification
| Designation | 7224 BM /DB |
| Type | Matched pair of angular contact ball bearings (back-to-back) |
| Series | 72 light (pair) |
| Bore diameter d | 120 mm |
| Outside diameter D | 215 mm |
| Basic dynamic load rating C | 267.3 kN (267,300 N) |
| Basic static load rating C0 | 326 kN (326,000 N) |
| Ratio C0/C | 1.22 |
| Speed guide, grease lubrication | 3,600 rpm |
| Life exponent p | 3 (ball bearing) |
Values come from the Rotec AI bearing catalogue and are indicative. Confirm against the manufacturer's current catalogue before ordering. Not every dimension (such as width) is listed here.
What the designation 7224 BM /DB means
| Code | Meaning |
|---|---|
| 72 | Angular contact ball bearing, light dimension series |
| 24 | bore code "24" = 24 × 5 = 120 mm |
| B | 40° contact angle |
| /DB | Two bearings mounted back-to-back as a matched pair — carries combined radial + axial load from both directions with high stiffness |
Basic rating life of the 7224 BM /DB
Basic rating life is L10 = (C / P)p million revolutions, where P is the equivalent dynamic load and p = 3 (ball bearing). For a 7224 BM /DB with C = 267.3 kN, the table shows what that gives at different load levels. It is the ISO 281 basic life only: it does not include lubrication, contamination, misalignment or reliability modifiers.
| C / P | P as share of C | L10 (million rev) | L10 at 1,500 rpm | L10 at 3,000 rpm |
|---|---|---|---|---|
| 3 | 33.3% | 27 | 300 | 150 |
| 5 | 20.0% | 125 | 1,400 | 690 |
| 8 | 12.5% | 512 | 5,700 | 2,800 |
| 12 | 8.3% | 1,728 | 19,200 | 9,600 |
For example, a C / P of 5 means the equivalent load is 53.46 kN on this bearing. Use the Load Calculator to work out P for your actual radial and axial loads.
Equivalents of the 7224 BM /DB
Brand-by-brand equivalents for this exact designation are not yet in the Rotec AI cross-reference tables. The Cross-Reference tool accepts SKF, FAG, NSK, NTN, Timken, Koyo and NRB designations, and shows what is catalogued.
Where the 7224 BM /DB is used
Angular-contact ball bearings are chosen for: Combined radial and axial load; precision/high-speed arrangements. Typical equipment: Pumps, compressors, spindles, generators, aerospace accessories. Often paired/preloaded; contact angle and lubrication matter.
Other sizes in the same series
The 7224 BM /DB is size 23 of 31 in the Rotec AI catalogue for the “72 light (pair)” series. The next size down, the 7222 BEP /DB, has a bore of 110 mm and a dynamic rating of 247.86 kN. The next size up, the 7226 BM /DB, has a bore of 130 mm and a rating of 301.32 kN (+13%).
Common problems on bearings like the 7224 BM /DB
Most field failures trace back to lubrication, contamination, fits and alignment rather than the bearing itself. These guides explain how to recognise and prevent them:
Questions about the 7224 BM /DB
What are the dimensions of a 7224 BM /DB bearing?
The 7224 BM /DB has a bore of 120 mm and an outside diameter of 215 mm. It is a matched pair of angular contact ball bearings (back-to-back). Series: 72 light (pair).
What is the load rating of a 7224 BM /DB bearing?
In the Rotec AI catalogue the 7224 BM /DB has a basic dynamic load rating C of 267.3 kN and a basic static load rating C0 of 326 kN. Always confirm against the manufacturer's current catalogue.
What is the equivalent of a 7224 BM /DB bearing?
Brand equivalents for the 7224 BM /DB are not yet in the Rotec AI tables. Use the Cross-Reference tool to check other designations.