61968-MA bearing: complete specifications & equivalents
The 61968-MA is a ISO 15 radial bearing sized 340 x 460 x 56 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 340 mm |
| Outer diameter D | 460 mm |
| Width B | 56 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 281 kN |
| Basic static load rating C0 | 425 kN |
| Fatigue load limit Pu | 9 kN |
| Reference speed (thermal) | 2600 rpm |
| Limiting speed (mechanical) | 2200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 26500 g |
| Manufacturer designation | 61968 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 | 13.386 in |
|---|---|
| Outer diameter D | 18.11 in |
| Width B | 2.205 in |
| ISO bore code | 68 |
| Radial section height (D−d)/2 | 60 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) | 46 of 63 |
| Bore above smallest 61900-series size | 337 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61968 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing NTN 6968 on the same 340×460×56 mm envelope, but catalogue C/C0 differ (281/425 kN vs 325/430 kN) — envelope interchange only after a load check. |
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 61968-MA model number is decoded
In the 61900-series, the last two digits encode the bore: 61968 carries code 68 = 340 mm (code × 5). The envelope is 340×460×56 mm (13.386×18.11×2.205 in) with a 60.0 mm radial section height, C 281 kN, C0 425 kN and Pu 9 kN. The open 61968 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 2200 r/min, catalogue mass 26500 g. A thin section saves space but leaves little margin for misalignment or shaft deflection.
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
- cage damage from running beyond the limiting speed
- raceway smearing under marginal lubrication at start-up
Selection pitfalls — read before you substitute
- Fillet radii must clear the 61968-MA chamfer so the 56 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. 61968-2Z/C3 in SKF spelling); no suffix means normal CN internal clearance.
- The MA suffix on 61968-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 26500 g quoted mass includes the heavier cage.
- Open 61968-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 61968-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Fillet radii must clear the 61968-MA chamfer so the 56 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
Frequently asked questions
What are the dimensions of 61968-MA?
The SKF 61968 MA measures 340 mm bore × 460 mm OD × 56 mm width (13.386 × 18.11 × 2.205 in), mass about 26500 g. It is open, with no shields or seals.
How does the bore code in 61968 work?
The final two digits of 61968 are bore code 68, multiplied by 5 to give 340 mm.
Which fits should I use for 61968-MA?
With a rotating inner ring use roughly m6 on the shaft and H7 in the 460 mm housing; reverse the interference if the outer ring rotates.
How heavy is 61968-MA?
Catalogue mass is 26500 g for 61968 MA; seal and cage executions of the same envelope differ by a few grams.
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.