NCF2938-CV bearing: complete specifications & equivalents
The NCF2938-CV is a ISO 15 radial bearing sized 190 x 260 x 42 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 | 42 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | none |
| Basic dynamic load rating C | 440 kN |
| Basic static load rating C0 | 780 kN |
| Fatigue load limit Pu | 81.5 kN |
| Reference speed (thermal) | 1100 rpm |
| Limiting speed (mechanical) | 1400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 6500 g |
| Manufacturer designation | SKF NCF 2938 CV |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.3 single-row full complement cylindrical roller bearings |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.3 single-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. 6.3 single-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 & NCF2900-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 10.236 in |
| Width B | 1.654 in |
| ISO bore code | 38 |
| Radial section height (D−d)/2 | 35 mm |
| Smallest bore in NCF2900-series | 60 mm |
| Largest outer diameter in NCF2900-series | 1250 mm |
| Width range across NCF2900-series | 16–175 mm |
| Bore position in NCF2900-series (smallest first) | 17 of 44 |
| Bore above smallest NCF2900-series size | 130 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the NCF2938-CV model number is decoded
SKF NCF 2938 CV is a single-row full-complement cylindrical roller bearing sized 190×260×42 mm — a dimension series 29 (compact OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.3. Structurally, the NCF design has a non-separable single-row full complement bearing with two integral flanges on the inner ring, one integral flange on the outer ring and a retaining ring opposite that flange holding the assembly together. In arrangement terms it is one-direction locating: the integral outer-ring flange locates the shaft in one direction; the retaining ring side must not be used to guide axial displacement. 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 6500 g; at 440 kN dynamic rating this is roughly 2.32 kN of C per millimetre of bore before application factors. Mounting: uncaged rollers demand adequate minimum load and gentle acceleration; do not load the retaining ring axially and relubricate generously to prevent roller smearing. 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
- large rolling-mill and continuous-caster drives
- mining crusher eccentric shafts
- heavy offshore 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 (microwelding) in the full complement during skidding at light load or rapid acceleration
- 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
- edge loading and roller-end scoring when the minimum radial load is not maintained at standstill
- hard-particle indentation of the raceway in unfiltered oil systems
Selection pitfalls — read before you substitute
- Full-complement bearings trade speed for capacity: the 1,400 r/min ceiling is far below a caged bearing of the same envelope, and running faster smears the uncaged rollers.
- Keep minimum radial load high (typically ≥0,02 C) for a full-complement unit; at light load the rollers skid and microweld within the first service interval.
- Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
- Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 260 mm raceway.
- The 440/780 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 NCF2938-CV?
SKF NCF 2938 CV is a single-row full-complement cylindrical roller bearing with 190 mm bore, 260 mm OD and 42 mm width per ISO 15. SKF lists C 440 kN, C0 780 kN, Pu 81.5 kN, reference speed 1,100 r/min and limiting speed 1,400 r/min, mass about 6500 g.
What does the NCF 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 single-row full complement bearing with two integral flanges on the inner ring, one integral flange on the outer ring and a retaining ring opposite that flange holding the assembly together.
Can NCF2938-CV take axial load and locate the shaft?
In one direction, against the integral outer-ring flange side. The retaining ring holds the bearing together and must not be axially loaded.
How does NCF2938-CV compare with the other executions in the same envelope?
The full-complement NCF/NJG bearings replace the cage with extra rollers for higher radial capacity and stiffness at a substantially lower speed than caged bearings.
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. 6.3 single-row full complement cylindrical roller bearings on 2026-09-26. Read our editorial & correction policy.