6228-MA (brass cage) bearing: complete specifications & equivalents
The 6228-MA is a ISO 15 radial bearing sized 140 x 250 x 42 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 140 mm |
| Outer diameter D | 250 mm |
| Width B | 42 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 165 kN |
| Basic static load rating C0 | 150 kN |
| Fatigue load limit Pu | 4.55 kN |
| Reference speed (thermal) | 5300 rpm |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 9400 g |
| Manufacturer designation | 6228 MA |
| 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 | 5.512 in |
|---|---|
| Outer diameter D | 9.843 in |
| Width B | 1.654 in |
| ISO bore code | 28 |
| Radial section height (D−d)/2 | 55 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) | 34 of 45 |
| Bore above smallest 6200-series size | 137 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 6228-FAG | FAG | partial Main dimensions match; tolerances, seals or internal clearance differ. | FAG bearing FAG 6228 on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 188/165 kN) — envelope interchange only after a load check. |
| 6228-2RS | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6228DDU on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 183/150 kN) — envelope interchange only after a load check. |
| 6228-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6228ZZ on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 183/150 kN) — envelope interchange only after a load check. |
| 6228-NSK | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | NSK bearing NSK 6228 on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 183/150 kN) — envelope interchange only after a load check. |
| 6228-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing 6228 on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 184/150 kN) — envelope interchange only after a load check. |
| 6228-2RS-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing 6228LLU on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 184/150 kN) — envelope interchange only after a load check. |
| 6228-ZZ-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing 6228ZZ on the same 140×250×42 mm envelope, but catalogue C/C0 differ (165/150 kN vs 184/150 kN) — envelope interchange only after a load check. |
| 6228 | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 6228 (open arrangement) shares the 140×250×42 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 6228-MA model number is decoded
In the 6200-series, the last two digits encode the bore: 6228 carries code 28 = 140 mm (code × 5). The envelope is 140×250×42 mm (5.512×9.843×1.654 in) with a 55.0 mm radial section height, C 165 kN, C0 150 kN and Pu 4.55 kN. The open 6228 MA carries no shields or seals and relies on application lubrication and external sealing. The MA suffix identifies the machined brass cage execution, a separate order number from the pressed-steel version. Limiting speed 4800 r/min, catalogue mass 9400 g.
Typical equipment & failure modes
Common applications
- heavy conveyor drives
- hoists and winches
- industrial fans and blowers
- mill and kiln auxiliaries
Known failure patterns
- contamination wear when the open arrangement is used without external seals
- lubricant starvation where no regreasing interval is maintained
- electrical pitting in VFD-driven motors without shaft grounding
- edge loading from shaft deflection or housing misalignment
Selection pitfalls — read before you substitute
- Assign interference to the rotating ring: on a conventional shaft-mounted 140 mm position the inner ring rotates, so use a k5/m6 shaft seat with an H7 housing — reverse the logic if the outer ring rotates.
- Clearance suffixes follow the seal code in the designation stack (e.g. 6228-2Z/C3 in SKF spelling); no suffix means normal CN internal clearance.
- The MA suffix on 6228-MA 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 9400 g quoted mass includes the heavier cage.
- Open 6228-MA 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 6228-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Clearance suffixes follow the seal code in the designation stack (e.g. 6228-2Z/C3 in SKF spelling); no suffix means normal CN internal clearance.
- 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.
- SKF date-codes its packaging, and greased sealed or shielded bearings carry a finite shelf life: rotate stock first-in-first-out and store boxes dry, cool and away from vibration.
Frequently asked questions
What are the dimensions of 6228-MA?
The SKF 6228 MA measures 140 mm bore × 250 mm OD × 42 mm width (5.512 × 9.843 × 1.654 in), mass about 9400 g. It is open, with no shields or seals.
How does the bore code in 6228 work?
The final two digits of 6228 are bore code 28, multiplied by 5 to give 140 mm.
How long can a greased 6228-MA 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.
What load can 6228-MA take?
Catalogue values for 6228 MA: dynamic C 165 kN, static C0 150 kN, fatigue limit Pu 4.55 kN. Use C in life calculation and C0 for static checks at 140 mm bore.
What is the speed rating of 6228-MA?
SKF lists a 5300 r/min thermal reference speed and a 4800 r/min mechanical limiting speed for 6228 MA; real limits also depend on lubrication and fits.
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.