C4908-V bearing: complete specifications & equivalents
The C4908-V is a ISO 15 radial bearing sized 40 x 62 x 22 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 40 mm |
| Outer diameter D | 62 mm |
| Width B | 22 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 76.5 kN |
| Basic static load rating C0 | 100 kN |
| Fatigue load limit Pu | 11.8 kN |
| Limiting speed (mechanical) | 4300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 250 g |
| Manufacturer designation | C 4908 V |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings |
| Last verified | 2026-09-27 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings) · extracted 2026-09-27
Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal 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 & C4900-series range
| Bore d | 1.575 in |
|---|---|
| Outer diameter D | 2.441 in |
| Width B | 0.866 in |
| ISO bore code | 08 |
| Radial section height (D−d)/2 | 11 mm |
| Smallest bore in C4900-series | 40 mm |
| Largest outer diameter in C4900-series | 1460 mm |
| Width range across C4900-series | 22–335 mm |
| Bore position in C4900-series (smallest first) | 1 of 3 |
| Bore above smallest C4900-series size | 0 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the C4908-V model number is decoded
The CARB bearing C 4908 V combines the self-aligning behaviour of a spherical roller bearing with the axial freedom of a cylindrical bearing in one 40 mm bore, 62 mm outside diameter, 22 mm wide unit rated 76.5 kN dynamic. SKF builds the CARB order number from size plus execution: the bare number C 4908 is the full-complement cylindrical-bore bearing, K (or K30) makes the bore tapered for sleeve mounting, and the cage/seal letters follow — here V. The open execution relies on the housing seals and lubrication system, fed through groove/hole features on the large sizes. Explorer-class heat treatment and the crowned roller profile keep edge stress down when the 40 mm shaft deflects; no reference speed is listed and the limiting speed is 4,300 r/min. No thermal reference speed is listed for this full-complement execution; the mechanical limiting speed is 4,300 r/min. The full-complement V executions carry more load but list no thermal reference speed; the steel-caged executions run faster and cooler at light load. Open executions accept relubrication — route it through the outer-ring groove on sizes that have one and purge stale grease at service intervals. Grease through the annular groove features where provided; on open executions feed lubricant past the long roller set at assembly, since the 22 mm wide cavity does not fill itself.
Typical equipment & failure modes
Common applications
- paper machine drying cylinders and calender rolls with long, thermally expanding shafts
- continuous-caster guide rolls and slab-caster segments under heat growth
- vibrating screen exciters fitted with the VE240 tolerance execution
- long fan and kiln main shafts where the free end must float without thrust load
Known failure patterns
- roller-end and flange smearing after lubricant starvation at the long roller contacts
- thermal preloading when a shaft is located at both ends and growth has nowhere to go
- brass cage pocket wear under marginal lubrication in the large-bore M/MB executions
- condensation pitting in machines that run intermittently in humid environments
- abrasive paste forming as dust bypasses the housing seals into the open washer set
Selection pitfalls — read before you substitute
- At 40 mm bore the small CARB executions are unusually wide (22 mm) for their 62 mm OD — confirm the housing width before substituting a standard spherical bearing of the same bore.
- Envelope-identical spherical roller bearings (same ISO 15 d×D×B) are not drop-in equivalents — they locate the shaft axially, while C 4908 V must float; the two are designed to be used as a pair.
- Never use C 4908 V as the locating bearing: it carries no axial load by design — the arrangement needs a separate locating spherical, tapered or angular bearing facing the thrust.
- Do not block the axial displacement in the drawing: housing covers, labyrinth rings and snap rings must leave the catalogue float (s) free, or the bearing silently becomes a poorly located fixed bearing.
- Tapered-bore K executions mount on adapter sleeves (1:12) and K30 on withdrawal sleeves (1:30) — the 40 mm bore changes the sleeve family, and the drive-up procedure differs accordingly.
- The 76.5/100 kN ratings and 250 g mass are SKF catalogue values transcribed from ch. 10.1 of PUB BU/P1 17000 (PDF table page 858); mounting data — axial displacement (s) and seating details — appears in the running text because the structured record carries the boundary envelope only.
Frequently asked questions
What fails first on a misapplied CARB bearing?
Blocking the designed axial float — clamping the free end or locating both shaft ends — turns thermal growth into edge loading and spalls the toroidal raceways. Cage damage and ordinary fatigue follow overload or dry running.
Which dimensions does the C 4908 V have?
A C 4908 V measures 40 mm bore × 62 mm outside diameter × 22 mm width (1.575 × 2.441 × 0.866 in). From SKF catalogue PUB BU/P1 17000: dynamic C 76.5 kN, static C0 100 kN, fatigue limit Pu 11.8 kN, limiting speed 4,300 r/min, no reference speed listed, mass about 250 g.
What does C 4908 V mean in SKF part numbering?
C marks CARB; 49 the dimension series; the size code gives 40 mm bore; V is the execution (cylindrical bore for direct shaft fitting, full-complement V execution (no cage)). The envelope follows ISO 15 and matches spherical roller bearing outlines, but the functions differ.
Why is C 4908 V used opposite a spherical roller bearing?
The spherical bearing locates the shaft and takes thrust; the CARB bearing at the other end self-aligns but floats, absorbing thermal expansion without inducing axial load. The pair is standard on paper machine drying cylinders and long caster rolls.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 10.1 CARB toroidal roller bearings on 2026-09-27. Read our editorial & correction policy.