NCF2334-ECJB-PEX bearing: complete specifications & equivalents
The NCF2334-ECJB-PEX is a ISO 15 radial bearing sized 170 x 360 x 120 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 170 mm |
| Outer diameter D | 360 mm |
| Width B | 120 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 1760 kN |
| Basic static load rating C0 | 2200 kN |
| Fatigue load limit Pu | 216 kN |
| Reference speed (thermal) | 1900 rpm |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 58500 g |
| Manufacturer designation | SKF NCF 2334 ECJB/PEX |
| 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 & NCF2300-series range
| Bore d | 6.693 in |
|---|---|
| Outer diameter D | 14.173 in |
| Width B | 4.724 in |
| ISO bore code | 34 |
| Radial section height (D−d)/2 | 95 mm |
| Smallest bore in NCF2300-series | 130 mm |
| Largest outer diameter in NCF2300-series | 460 mm |
| Width range across NCF2300-series | 93–145 mm |
| Bore position in NCF2300-series (smallest first) | 5 of 9 |
| Bore above smallest NCF2300-series size | 40 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NCF2334-ECJB | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same ISO 15 envelope 170×360×120 mm, but catalogue C/C0 ratings differ between executions (1760/2200 vs 1540/2200 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent. |
| NUH2334-ECMH | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same ISO 15 envelope 170×360×120 mm, but catalogue C/C0 ratings differ between executions (1760/2200 vs 1540/2200 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent. |
| NUH2334-ECMH-PEX | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 170×360×120 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 NCF2334-ECJB-PEX model number is decoded
In SKF catalogue PUB BU/P1 17000, SKF NCF 2334 ECJB/PEX denotes a high-capacity cylindrical roller bearing on the ISO 15 170×360×120 mm envelope, dimension series 23 (medium-section, wide), with catalogue mass 58500 g. 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. The radial section height is 95.0 mm and the catalogue mass 58500 g; at 1760 kN dynamic rating this is roughly 10.35 kN of C per millimetre of bore before application factors. 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. The /PEX mark identifies the pinion-shaft build: it is the execution developed for the pinion position in wind-turbine and heavy industrial gearboxes, and SKF publishes its own rating line (C 1760 kN / C0 2200 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NCF2334-ECJB-PEX as a separate service part: do not substitute the standard NCF 2334 bearing against the /PEX loads, and refit pinion arrangements with the same /PEX order number to preserve the calculated L10 and peak-torque margin.
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
- cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up
- roller-end scoring from inadequate oil flow in the roller-raceway contact
- cage fatigue in heavily reversing wind-turbine load cycles when relubrication intervals are exceeded
- 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
- 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 build and the standard NCF 2334 bearing are separate service parts with different internal profiling and rating lines; replacing the /PEX part with the standard execution silently erases the peak-torque margin the gearbox was designed for.
- Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 120 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 1760/2200 kN ratings are SKF catalogue 17000 (2018) values for the ECJB/PEX 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 NCF2334-ECJB-PEX?
SKF NCF 2334 ECJB/PEX is a high-capacity cylindrical roller bearing with 170 mm bore, 360 mm OD and 120 mm width per ISO 15. SKF lists C 1760 kN, C0 2200 kN, Pu 216 kN, reference speed 1,900 r/min and limiting speed 2,600 r/min, mass about 58500 g.
What does the NCF designation and ECJB/PEX 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 NCF2334-ECJB-PEX 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 NCF2334-ECJB-PEX 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.