NNCL4938-CV bearing: complete specifications & equivalents
The NNCL4938-CV is a ISO 15 radial bearing sized 190 x 260 x 69 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 | 260 mm |
| Width B | 69 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 605 kN |
| Basic static load rating C0 | 1290 kN |
| Fatigue load limit Pu | 132 kN |
| Reference speed (thermal) | 1100 rpm |
| Limiting speed (mechanical) | 1400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 11000 g |
| Manufacturer designation | SKF NNCL 4938 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 & NNCL4900-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 10.236 in |
| Width B | 2.717 in |
| ISO bore code | 38 |
| Radial section height (D−d)/2 | 35 mm |
| Smallest bore in NNCL4900-series | 60 mm |
| Largest outer diameter in NNCL4900-series | 540 mm |
| Width range across NNCL4900-series | 25–140 mm |
| Bore position in NNCL4900-series (smallest first) | 14 of 25 |
| Bore above smallest NNCL4900-series size | 130 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NNC4938-CV | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 190×260×69 mm and equivalent catalogue ratings; the NNC execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NNCF4938-CV | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 190×260×69 mm and equivalent catalogue ratings; the NNCF 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 NNCL4938-CV model number is decoded
For a 190 mm shaft, SKF lists NNCL4938-CV as double-row full-complement cylindrical roller: 260 mm OD, 69 mm wide, Pu 132 kN, the catalogue lists 1,100 r/min thermal reference speed and 1,400 r/min mechanical limiting speed. Reading the NNCL prefix: a double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set. This makes the execution non-locating: the outer ring can be displaced axially, like an NN design, to absorb shaft expansion. 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 35.0 mm and the catalogue mass 11000 g; at 605 kN dynamic rating this is roughly 3.18 kN of C per millimetre of bore before application factors. Mounting: treat the outer ring as the floating element; keep the inner ring with its three flanges square on the shaft and relubricate through the outer-ring groove. A 190 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.
Typical equipment & failure modes
Common applications
- mining shovel and dragline pivots
- steelmaking and heavy crane sheaves
- large offshore winch and hook blocks
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
- roller-end scoring from inadequate oil flow in the roller-raceway contact
- uneven row loading from misalignment, concentrating fatigue on one row of the double complement
- edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)
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 69 mm-wide ring and concentrates load.
- Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.
- The 605/1290 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 NNCL4938-CV?
SKF NNCL 4938 CV is a double-row full-complement cylindrical roller bearing with 190 mm bore, 260 mm OD and 69 mm width per ISO 15. SKF lists C 605 kN, C0 1290 kN, Pu 132 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 11000 g.
What does the NNCL 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 double-row full complement bearing with three integral flanges on the inner ring and no retaining ring in the smooth outer ring, which is free to pass over the roller set.
Can NNCL4938-CV take axial load and locate the shaft?
No — the smooth outer ring floats, making NNCL the non-locating member of the arrangement.
How does NNCL4938-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.