NNCF4838-CV bearing: complete specifications & equivalents
The NNCF4838-CV is a ISO 15 radial bearing sized 190 x 240 x 50 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 190 mm |
| Outer diameter D | 240 mm |
| Width B | 50 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 358 kN |
| Basic static load rating C0 | 750 kN |
| Fatigue load limit Pu | 76.5 kN |
| Reference speed (thermal) | 1100 rpm |
| Limiting speed (mechanical) | 1400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5500 g |
| Manufacturer designation | SKF NNCF 4838 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 & NNCF4800-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 9.449 in |
| Width B | 1.969 in |
| ISO bore code | 38 |
| Radial section height (D−d)/2 | 25 mm |
| Smallest bore in NNCF4800-series | 150 mm |
| Largest outer diameter in NNCF4800-series | 500 mm |
| Width range across NNCF4800-series | 40–100 mm |
| Bore position in NNCF4800-series (smallest first) | 5 of 16 |
| Bore above smallest NNCF4800-series size | 40 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NNC4838-CV | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 190×240×50 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NNCL4838-CV | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 190×240×50 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 NNCF4838-CV model number is decoded
NNCF4838-CV is the 190 mm bore entry in the NNCF4800 range: a 190×240×50 mm double-row full-complement cylindrical roller bearing with a full complement of extra rollers fitted in place of a cage, rated C 358 kN / C0 750 kN. Reading the NNCF prefix: a non-separable double-row full complement bearing with three integral flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes. This makes the execution one-direction locating: the retained outer ring guides the shaft axially in one direction. 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. The radial section height is 25.0 mm and the catalogue mass 5500 g; at 358 kN dynamic rating this is roughly 1.88 kN of C per millimetre of bore before application factors. Fit practice for NNCF4838-CV: the retaining ring must never be loaded axially in operation; route relubrication through the outer-ring groove and keep the unit non-separable during handling. 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
- large offshore winch and hook blocks
- mining shovel and dragline pivots
- steelmaking and heavy crane sheaves
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
- cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up
- 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
- hard-particle indentation of the raceway in unfiltered oil systems
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.
- Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.
- Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 50 mm-wide ring and concentrates load.
- The 358/750 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 NNCF4838-CV?
SKF NNCF 4838 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 240 mm OD and 50 mm width per ISO 15. SKF lists C 358 kN, C0 750 kN, Pu 76.5 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 5500 g.
What does the NNCF 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 flanges on the inner ring and one retaining ring in the outer ring; the outer ring also has an annular lubrication groove with holes.
Can NNCF4838-CV take axial load and locate the shaft?
In one direction, via the retained outer ring; the retaining ring is not a load path for continuous thrust.
How does NNCF4838-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.