61934-MA bearing: complete specifications & equivalents
The 61934-MA is a ISO 15 radial bearing sized 170 x 230 x 28 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 170 mm |
| Outer diameter D | 230 mm |
| Width B | 28 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 93.6 kN |
| Basic static load rating C0 | 106 kN |
| Fatigue load limit Pu | 3.15 kN |
| Reference speed (thermal) | 5600 rpm |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 3350 g |
| Manufacturer designation | 61934 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 | 6.693 in |
|---|---|
| Outer diameter D | 9.055 in |
| Width B | 1.102 in |
| ISO bore code | 34 |
| Radial section height (D−d)/2 | 30 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) | 36 of 63 |
| Bore above smallest 61900-series size | 167 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 61934 | NSK | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
| 61934-ZZ | NSK | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 170×230×28 mm envelope per ISO 15; seal variant differs (OPEN vs ZZ) — confirm sealing suits the duty. |
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 61934-MA model number is decoded
In the 61900-series, the last two digits encode the bore: 61934 carries code 34 = 170 mm (code × 5). The envelope is 170×230×28 mm (6.693×9.055×1.102 in) with a 30.0 mm radial section height, C 93.6 kN, C0 106 kN and Pu 3.15 kN. The open 61934 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 3350 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
- fretting corrosion on a creeping shaft or housing seat
- cage damage from running beyond the limiting speed
Selection pitfalls — read before you substitute
- At 170 mm bore, C3 clearance is the safe choice when interference fits plus temperature rise consume the CN clearance; a hot tight bearing with no residual clearance fails fast.
- Catalogue ratings for 61934-MA (C 93.6 kN, C0 106 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 61934-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 3350 g quoted mass includes the heavier cage.
- Open 61934-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 61934-MA; run-to-failure on open deep-groove bearings is the dominant early-failure cause.
- Assign interference to the rotating ring: on a conventional shaft-mounted 170 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.
Frequently asked questions
What are the dimensions of 61934-MA?
The SKF 61934 MA measures 170 mm bore × 230 mm OD × 28 mm width (6.693 × 9.055 × 1.102 in), mass about 3350 g. It is open, with no shields or seals.
How does the bore code in 61934 work?
The final two digits of 61934 are bore code 34, multiplied by 5 to give 170 mm.
What load can 61934-MA take?
Catalogue values for 61934 MA: dynamic C 93.6 kN, static C0 106 kN, fatigue limit Pu 3.15 kN. Use C in life calculation and C0 for static checks at 170 mm bore.
What is the speed rating of 61934-MA?
SKF lists a 5600 r/min thermal reference speed and a 4800 r/min mechanical limiting speed for 61934 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.