61956-MA bearing: complete specifications & equivalents
The 61956-MA is a ISO 15 radial bearing sized 280 x 380 x 46 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 280 mm |
| Outer diameter D | 380 mm |
| Width B | 46 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 216 kN |
| Basic static load rating C0 | 285 kN |
| Fatigue load limit Pu | 6.7 kN |
| Reference speed (thermal) | 3200 rpm |
| Limiting speed (mechanical) | 2800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 15500 g |
| Manufacturer designation | 61956 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 & 61900-series range
| Bore d | 11.024 in |
|---|---|
| Outer diameter D | 14.961 in |
| Width B | 1.811 in |
| ISO bore code | 56 |
| Radial section height (D−d)/2 | 50 mm |
| Smallest bore in 61900-series | 3 mm |
| Largest outer diameter in 61900-series | 1120 mm |
| Width range across 61900-series | 3–118 mm |
| Bore position in 61900-series (smallest first) | 43 of 63 |
| Bore above smallest 61900-series size | 277 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61956 | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 61956 (open arrangement) shares the 280×380×46 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 61956-MA model number is decoded
In the 61900-series, the last two digits encode the bore: 61956 carries code 56 = 280 mm (code × 5). The envelope is 280×380×46 mm (11.024×14.961×1.811 in) with a 50.0 mm radial section height, C 216 kN, C0 285 kN and Pu 6.7 kN. The open 61956 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 2800 r/min, catalogue mass 15500 g. A thin section saves space but leaves little margin for misalignment or shaft deflection.
Typical equipment & failure modes
Common applications
- space-constrained gearboxes
- clutch and transmission assemblies
- robotics and automation joints
- lay shafts and idler shafts
Known failure patterns
- contamination wear when the open arrangement is used without external seals
- lubricant starvation where no regreasing interval is maintained
- fretting corrosion on a creeping shaft or housing seat
- cage damage from running beyond the limiting speed
Selection pitfalls — read before you substitute
- Fillet radii must clear the 61956-MA chamfer so the 46 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
- Clearance suffixes follow the seal code in the designation stack (e.g. 61956-2Z/C3 in SKF spelling); no suffix means normal CN internal clearance.
- The MA suffix on 61956-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 15500 g quoted mass includes the heavier cage.
- Open 61956-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 61956-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Deep-groove geometry tolerates only minutes of misalignment; if the 380 mm housing bore cannot be aligned, move to a self-aligning bearing rather than shimming 61956-MA.
Frequently asked questions
What are the dimensions of 61956-MA?
The SKF 61956 MA measures 280 mm bore × 380 mm OD × 46 mm width (11.024 × 14.961 × 1.811 in), mass about 15500 g. It is open, with no shields or seals.
How does the bore code in 61956 work?
The final two digits of 61956 are bore code 56, multiplied by 5 to give 280 mm.
How heavy is 61956-MA?
Catalogue mass is 15500 g for 61956 MA; seal and cage executions of the same envelope differ by a few grams.
What load can 61956-MA take?
Catalogue values for 61956 MA: dynamic C 216 kN, static C0 285 kN, fatigue limit Pu 6.7 kN. Use C in life calculation and C0 for static checks at 280 mm bore.
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.