NCF2238-ECJB bearing: complete specifications & equivalents
The NCF2238-ECJB is a ISO 15 radial bearing sized 190 x 340 x 92 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 | 340 mm |
| Width B | 92 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 1320 kN |
| Basic static load rating C0 | 1760 kN |
| Fatigue load limit Pu | 180 kN |
| Reference speed (thermal) | 2000 rpm |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 36500 g |
| Manufacturer designation | SKF NCF 2238 ECJB |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity 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. 6.2 high-capacity 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 & NCF2200-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 13.386 in |
| Width B | 3.622 in |
| ISO bore code | 38 |
| Radial section height (D−d)/2 | 75 mm |
| Smallest bore in NCF2200-series | 120 mm |
| Largest outer diameter in NCF2200-series | 400 mm |
| Width range across NCF2200-series | 58–108 mm |
| Bore position in NCF2200-series (smallest first) | 7 of 9 |
| Bore above smallest NCF2200-series size | 70 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NUH2238-ECMH | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 190×340×92 mm and equivalent catalogue ratings; the NUH 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 NCF2238-ECJB model number is decoded
Ordering number SKF NCF 2238 ECJB resolves to a 190×340×92 mm high-capacity cylindrical roller bearing (dimension series 22 (light-section, wide)); the high-capacity caged partner execution (ECJB pressed-steel cages with displaced cage bars for extra rollers), matching the NUH bearing in the same dimension envelope. Reading the NCF prefix: the high-capacity caged partner execution (ECJB pressed-steel cages with displaced cage bars for extra rollers), matching the NUH bearing in the same dimension envelope. This makes the execution the non-locating member of the paired high-capacity arrangement, absorbing axial displacement while carrying the full high radial rating. The ECJB suffix denotes the high-capacity execution with pressed-steel cages; /PEX marks the pinion-shaft special build with its own catalogue rating line. Selection arithmetic: C0/C ≈ 1.33 (1760 against 1320 kN), and the Pu figure 180 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 2,000 r/min thermal reference speed and 2,600 r/min mechanical limiting speed. Assembly note: used opposite the NUH locating bearing on wind-gearbox and heavy industrial pinion shafts; fit the inner ring with interference and let this bearing float axially. Heat steel rings inductively to max 120 °C. This is the standard catalogue execution of the high-capacity design. Selected sizes in the range are also produced as /PEX pinion-shaft builds for wind-turbine gearboxes — separate order numbers with their own rating lines and internal profiling; the two must not be mixed using one another’s loads.
Typical equipment & failure modes
Common applications
- multi-megawatt wind turbine main gearboxes
- offshore and marine heavy drive trains
- large mining mill pinion shafts
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
- micro-pitting on the profiled rollers under contaminated or starved-lubricant conditions despite the black-oxide treatment
- 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
- cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded
- rolling-contact fatigue spalling after the rated L10 life is exceeded
Selection pitfalls — read before you substitute
- High-capacity NUH and NCF bearings are designed as a locating/non-locating PAIR on the same shaft; fitting two locating NUH bearings can preload the arrangement thermally.
- The /PEX pinion execution carries its own rating line and internal geometry — never substitute a standard NCF 2238 using the /PEX loads.
- Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 92 mm-wide ring and concentrates load.
- Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
- The 1320/1760 kN ratings are SKF catalogue 17000 (2018) values for the ECJB 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 NCF2238-ECJB?
SKF NCF 2238 ECJB is a high-capacity cylindrical roller bearing with 190 mm bore, 340 mm OD and 92 mm width per ISO 15. SKF lists C 1320 kN, C0 1760 kN, Pu 180 kN, reference speed 2,000 r/min and limiting speed 2,600 r/min, mass about 36500 g.
What does the NCF designation and ECJB suffix mean?
The ECJB suffix denotes the high-capacity execution with pressed-steel cages; /PEX marks the pinion-shaft special build with its own catalogue rating line. Structurally this execution has the high-capacity caged partner execution (ECJB pressed-steel cages with displaced cage bars for extra rollers), matching the NUH bearing in the same dimension envelope.
Can NCF2238-ECJB take axial load and locate the shaft?
The high-capacity NCF ECJB execution is the non-locating partner in the NUH/NCF pair and should float axially.
How does NCF2238-ECJB compare with the other executions in the same envelope?
The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number.
What limits the service life of this bearing most often?
Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers.
Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.2 high-capacity cylindrical roller bearings on 2026-09-26. Read our editorial & correction policy.