61864-MA bearing: complete specifications & equivalents
The 61864-MA is a ISO 15 radial bearing sized 320 x 400 x 38 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 320 mm |
| Outer diameter D | 400 mm |
| Width B | 38 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 172 kN |
| Basic static load rating C0 | 255 kN |
| Fatigue load limit Pu | 5.7 kN |
| Reference speed (thermal) | 3000 rpm |
| Limiting speed (mechanical) | 2400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 11000 g |
| Manufacturer designation | 61864 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 & 61800-series range
| Bore d | 12.598 in |
|---|---|
| Outer diameter D | 15.748 in |
| Width B | 1.496 in |
| ISO bore code | 64 |
| Radial section height (D−d)/2 | 40 mm |
| Smallest bore in 61800-series | 1 mm |
| Largest outer diameter in 61800-series | 1820 mm |
| Width range across 61800-series | 1–140 mm |
| Bore position in 61800-series (smallest first) | 48 of 74 |
| Bore above smallest 61800-series size | 319 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61864 | SKF | full Dimensions and internal design equivalent — standard interchange. | SKF SKF 61864 (open arrangement) shares the 320×400×38 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 61864-MA model number is decoded
In the 61800-series, the last two digits encode the bore: 61864 carries code 64 = 320 mm (code × 5). The envelope is 320×400×38 mm (12.598×15.748×1.496 in) with a 40.0 mm radial section height, C 172 kN, C0 255 kN and Pu 5.7 kN. The open 61864 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 2400 r/min, catalogue mass 11000 g. A thin section saves space but leaves little margin for misalignment or shaft deflection.
Typical equipment & failure modes
Common applications
- textile and packaging machinery
- slew and indexing drives
- large industrial gearboxes
- heavy conveyor drives
Known failure patterns
- contamination wear when the open arrangement is used without external seals
- lubricant starvation where no regreasing interval is maintained
- raceway smearing under marginal lubrication at start-up
- electrical pitting in VFD-driven motors without shaft grounding
Selection pitfalls — read before you substitute
- Clearance suffixes follow the seal code in the designation stack (e.g. 61864-2Z/C3 in SKF spelling); no suffix means normal CN internal clearance.
- Catalogue ratings for 61864-MA (C 172 kN, C0 255 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.
- The MA suffix on 61864-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 11000 g quoted mass includes the heavier cage.
- Open 61864-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 61864-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Mount by heating the inner ring (max 120 °C) — driving 61864-MA home through the outer ring or balls brinells the raceways.
Frequently asked questions
What are the dimensions of 61864-MA?
The SKF 61864 MA measures 320 mm bore × 400 mm OD × 38 mm width (12.598 × 15.748 × 1.496 in), mass about 11000 g. It is open, with no shields or seals.
How does the bore code in 61864 work?
The final two digits of 61864 are bore code 64, multiplied by 5 to give 320 mm.
Which fits should I use for 61864-MA?
With a rotating inner ring use roughly m6 on the shaft and H7 in the 400 mm housing; reverse the interference if the outer ring rotates.
How heavy is 61864-MA?
Catalogue mass is 11000 g for 61864 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.