61884-MA bearing: complete specifications & equivalents
The 61884-MA is a ISO 15 radial bearing sized 420 x 520 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 | 420 mm |
| Outer diameter D | 520 mm |
| Width B | 46 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 251 kN |
| Basic static load rating C0 | 425 kN |
| Fatigue load limit Pu | 8.3 kN |
| Reference speed (thermal) | 2200 rpm |
| Limiting speed (mechanical) | 1800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 21500 g |
| Manufacturer designation | 61884 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 | 16.535 in |
|---|---|
| Outer diameter D | 20.472 in |
| Width B | 1.811 in |
| ISO bore code | 84 |
| Radial section height (D−d)/2 | 50 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) | 53 of 74 |
| Bore above smallest 61800-series size | 419 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61884 | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | NTN bearing NTN 6884 on the same 420×520×46 mm envelope, but catalogue C/C0 differ (251/425 kN vs 288/405 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 61884-MA model number is decoded
In the 61800-series, the last two digits encode the bore: 61884 carries code 84 = 420 mm (code × 5). The envelope is 420×520×46 mm (16.535×20.472×1.811 in) with a 50.0 mm radial section height, C 251 kN, C0 425 kN and Pu 8.3 kN. The open 61884 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 1800 r/min, catalogue mass 21500 g. A thin section saves space but leaves little margin for misalignment or shaft deflection.
Typical equipment & failure modes
Common applications
- hoists and winches
- industrial fans and blowers
- mill and kiln auxiliaries
- pulp and paper machinery
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
- Assign interference to the rotating ring: on a conventional shaft-mounted 420 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. 61884-2Z/C3 in SKF spelling); no suffix means normal CN internal clearance.
- The MA suffix on 61884-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 21500 g quoted mass includes the heavier cage.
- Open 61884-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 61884-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- The fatigue load limit is 8.3 kN; it feeds the equivalent-mean-load check, not the basic life calculation — do not substitute one for the other.
Frequently asked questions
What are the dimensions of 61884-MA?
The SKF 61884 MA measures 420 mm bore × 520 mm OD × 46 mm width (16.535 × 20.472 × 1.811 in), mass about 21500 g. It is open, with no shields or seals.
How does the bore code in 61884 work?
The final two digits of 61884 are bore code 84, multiplied by 5 to give 420 mm.
What is the difference between 61884-MA and a same-bore 62-series bearing?
Section height differs: 61884-MA has a 50 mm radial section and C 251 kN; always match d, D and B — same bore alone never makes two bearings interchangeable.
Which fits should I use for 61884-MA?
With a rotating inner ring use roughly m6 on the shaft and H7 in the 520 mm housing; reverse the interference if the outer ring rotates.
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.