NNC4912-CV bearing: complete specifications & equivalents
The NNC4912-CV is a ISO 15 radial bearing sized 60 x 85 x 25 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 60 mm |
| Outer diameter D | 85 mm |
| Width B | 25 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 78.1 kN |
| Basic static load rating C0 | 137 kN |
| Fatigue load limit Pu | 14.3 kN |
| Reference speed (thermal) | 3600 rpm |
| Limiting speed (mechanical) | 4500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 490 g |
| Manufacturer designation | SKF NNC 4912 CV |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings) · extracted 2026-09-26
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings); 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 & NNC4900-series range
| Bore d | 2.362 in |
|---|---|
| Outer diameter D | 3.346 in |
| Width B | 0.984 in |
| ISO bore code | 12 |
| Radial section height (D−d)/2 | 12.5 mm |
| Smallest bore in NNC4900-series | 60 mm |
| Largest outer diameter in NNC4900-series | 540 mm |
| Width range across NNC4900-series | 25–140 mm |
| Bore position in NNC4900-series (smallest first) | 1 of 25 |
| Bore above smallest NNC4900-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NNCF4912-CV | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 60×85×25 mm and equivalent catalogue ratings; the NNCF execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NNCL4912-CV | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 60×85×25 mm and equivalent catalogue ratings; the NNCL execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
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 NNC4912-CV model number is decoded
SKF NNC 4912 CV is a double-row full-complement cylindrical roller bearing sized 60×85×25 mm — a dimension series 49 (compact heavy section), listed in SKF catalogue PUB BU/P1 17000 ch. 6.4. The NNC configuration means a non-separable double-row full complement bearing with three integral inner-ring flanges and two retaining rings holding the outer ring on both sides; functionally the bearing is two-direction locating — the retaining-ring configuration closes both axial escape paths. Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Speed planning for NNC4912-CV: the catalogue lists 3,600 r/min thermal reference speed and 4,500 r/min mechanical limiting speed. The mass entry 490 g covers the complete catalogue execution. Fit practice for NNC4912-CV: check both retaining rings are seated in their grooves before installation; axial guidance in both directions makes this the locating pair member, so the mating bearing must float. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.
Typical equipment & failure modes
Common applications
- offshore crane sheaves
- heavy material-handling rope pulleys
- rolling-mill and caster drives
- large crane and winch drums
Known failure patterns
- inner-ring raceway spalling from overload or contamination in the line-contact hertz zone
- outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating
- roller smearing between the uncaged rollers during slow skidding starts under heavy static load
- polymer cage cracking or softening after sustained running above 120 °C or with incompatible lubricant
- surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load
- uneven row loading from misalignment, concentrating fatigue on one row of the double complement
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- The NNCF/NNCL/NNC triplet shares the envelope and ratings but differs in outer-ring retention — one retaining ring, none, or two; selecting the wrong one changes the axial-locating scheme.
- Relubrication must reach both roller rows through the annular groove; blocked lube holes starve one row silently and show later as asymmetric raceway wear.
- Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 85 mm raceway.
- Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 25 mm-wide ring and concentrates load.
- The 78.1/137 kN ratings are SKF catalogue 17000 (2018) values for the CV execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification.
Frequently asked questions
What are the dimensions and catalogue data of NNC4912-CV?
SKF NNC 4912 CV is a double-row full-complement cylindrical roller bearing with 60 mm bore, 85 mm OD and 25 mm width per ISO 15. SKF lists C 78.1 kN, C0 137 kN, Pu 14.3 kN, reference speed 3,600 r/min and limiting speed 4,500 r/min, mass about 490 g.
What does the NNC designation and CV suffix mean?
Suffix CV identifies the full-complement execution: the space a cage would occupy is filled with extra rollers, trading speed for maximum radial capacity and stiffness. Structurally this execution has a non-separable double-row full complement bearing with three integral inner-ring flanges and two retaining rings holding the outer ring on both sides.
Can NNC4912-CV take axial load and locate the shaft?
Yes, in both directions, because retaining rings close both sides of the outer ring; the paired bearing must then float.
How does NNC4912-CV compare with the other executions in the same envelope?
NNCF (one outer retaining ring, one-direction guidance), NNCL (no retaining ring, floating outer ring) and NNC (retaining rings both sides, two-direction location) share the ISO envelope and ratings but are not interchangeable in a locating arrangement.
What limits the service life of this bearing most often?
On full-complement bearings the dominant risks are roller smearing from skidding below minimum load and contamination; maintain minimum radial load, keep lubricant film thick and accelerate gently.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.4 double-row full complement cylindrical roller bearings on 2026-09-26. Read our editorial & correction policy.