6224-M (brass cage) bearing: complete specifications & equivalents
The 6224-M is a ISO 15 radial bearing sized 120 x 215 x 40 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 120 mm |
| Outer diameter D | 215 mm |
| Width B | 40 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 146 kN |
| Basic static load rating C0 | 118 kN |
| Fatigue load limit Pu | 3.9 kN |
| Reference speed (thermal) | 6300 rpm |
| Limiting speed (mechanical) | 5600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 6100 g |
| Manufacturer designation | 6224 M |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018) |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.
Dimensions in inches & 6200-series range
| Bore d | 4.724 in |
|---|---|
| Outer diameter D | 8.465 in |
| Width B | 1.575 in |
| ISO bore code | 24 |
| Radial section height (D−d)/2 | 47.5 mm |
| Smallest bore in 6200-series | 3 mm |
| Largest outer diameter in 6200-series | 540 mm |
| Width range across 6200-series | 2.5–85 mm |
| Bore position in 6200-series (smallest first) | 32 of 45 |
| Bore above smallest 6200-series size | 117 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6224-2RS-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6224DDU on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 171/131 kN) — envelope interchange only after a load check. |
| 6224-RSR | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6224VV on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 171/131 kN) — envelope interchange only after a load check. |
| 6224-ZZ-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6224ZZ on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 171/131 kN) — envelope interchange only after a load check. |
| 6224-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6224 on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 171/131 kN) — envelope interchange only after a load check. |
| 6224-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing 6224 on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 172/131 kN) — envelope interchange only after a load check. |
| 6224-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing 6224LLU on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 172/131 kN) — envelope interchange only after a load check. |
| 6224-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing 6224ZZ on the same 120×215×40 mm envelope, but catalogue C/C0 differ (146/118 kN vs 172/131 kN) — envelope interchange only after a load check. |
| 6224 | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 6224 (open arrangement) shares the 120×215×40 mm envelope with ratings within 10 % — execution variant of the same size; boundary dimensions interchangeable. |
| 6224-2RS | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 6224-2RS1 (two contact elastomer seals) shares the 120×215×40 mm envelope with ratings within 10 % — execution variant of the same size; boundary dimensions interchangeable. |
| 6224-ZZ | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 6224-2Z (two non-contact shields) shares the 120×215×40 mm envelope with ratings within 10 % — execution variant of the same size; boundary dimensions interchangeable. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 6224-M model number is decoded
In the 6200-series, the last two digits encode the bore: 6224 carries code 24 = 120 mm (code × 5). The envelope is 120×215×40 mm (4.724×8.465×1.575 in) with a 47.5 mm radial section height, C 146 kN, C0 118 kN and Pu 3.9 kN. The open 6224 M carries no shields or seals and relies on application lubrication and external sealing. The M suffix identifies the machined brass cage execution, a separate order number from the pressed-steel version. Limiting speed 5600 r/min, catalogue mass 6100 g.
Typical equipment & failure modes
Common applications
- machine tool auxiliaries
- agricultural gearboxes
- industrial electric motors
- gearboxes and speed reducers
Known failure patterns
- contamination wear when the open arrangement is used without external seals
- lubricant starvation where no regreasing interval is maintained
- edge loading from shaft deflection or housing misalignment
- rolling-contact fatigue spalling once the catalogue L10 life is exceeded
Selection pitfalls — read before you substitute
- Catalogue ratings for 6224-M (C 146 kN, C0 118 kN) are SKF figures from PUB BU/P1 17000; geometry revisions can change ratings without changing the designation, so keep the catalogue edition with the specification.
- Do not preload 6224-M to silence it: a deep-groove ball bearing is not angular-contact, and axial preload only raises temperature and shortens grease life.
- The M suffix on 6224-M denotes a machined brass cage: it is the choice for high speeds, marginal lubrication and shock/vibration duty, and it is temperature-tolerant where polymer cages are not — the 6100 g quoted mass includes the heavier cage.
- Open 6224-M needs external sealing at the arrangement level; in dusty housings its life depends entirely on those external seals and the regreasing schedule.
- Plan a relubrication interval for 6224-M; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Catalogue ratings for 6224-M (C 146 kN, C0 118 kN) are SKF figures from PUB BU/P1 17000; geometry revisions can change ratings without changing the designation, so keep the catalogue edition with the specification.
- SKF Explorer deep-groove bearings of this size are produced to tight internal-geometry control; rating revisions between catalogue years do not change the designation, so keep the catalogue edition with the machine documentation.
- Sealed SKF units are filled with a lithium-based grease for general service; food-grade, low-temperature and high-temperature fills are order options and are not field-interchangeable once the unit is sealed.
Frequently asked questions
What are the dimensions of 6224-M?
The SKF 6224 M measures 120 mm bore × 215 mm OD × 40 mm width (4.724 × 8.465 × 1.575 in), mass about 6100 g. It is open, with no shields or seals.
How does the bore code in 6224 work?
The final two digits of 6224 are bore code 24, multiplied by 5 to give 120 mm.
How heavy is 6224-M?
Catalogue mass is 6100 g for 6224 M; seal and cage executions of the same envelope differ by a few grams.
What internal clearance does 6224-M have?
Standard supply is normal CN radial clearance unless a suffix states otherwise; for tight fits or hot shafts SKF lists the C3 execution of the same size — the residual clearance left after mounting is what governs running life.
How long can a greased 6224-M be stored?
Sealed and shielded SKF units carry a finite grease shelf life: SKF recommends first-in-first-out stock rotation and dry, cool, vibration-free storage. Open units ship with rust preventive only and are greased at assembly.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018) on 2026-09-27. Read our editorial & correction policy.