NUH2344-ECMH-PEX bearing: complete specifications & equivalents
The NUH2344-ECMH-PEX is a ISO 15 radial bearing sized 220 x 460 x 145 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 220 mm |
| Outer diameter D | 460 mm |
| Width B | 145 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 2900 kN |
| Basic static load rating C0 | 3650 kN |
| Fatigue load limit Pu | 335 kN |
| Reference speed (thermal) | 1400 rpm |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 116000 g |
| Manufacturer designation | SKF NUH 2344 ECMH/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 & NUH2300-series range
| Bore d | 8.661 in |
|---|---|
| Outer diameter D | 18.11 in |
| Width B | 5.709 in |
| ISO bore code | 44 |
| Radial section height (D−d)/2 | 120 mm |
| Smallest bore in NUH2300-series | 100 mm |
| Largest outer diameter in NUH2300-series | 500 mm |
| Width range across NUH2300-series | 73–155 mm |
| Bore position in NUH2300-series (smallest first) | 12 of 13 |
| Bore above smallest NUH2300-series size | 120 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NCF2344-ECJB | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same ISO 15 envelope 220×460×145 mm, but catalogue C/C0 ratings differ between executions (2900/3650 vs 2510/3650 kN) and the NCF flange/ring configuration differs — envelope match, not a load-rating equivalent. |
| NUH2344-ECMH | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same ISO 15 envelope 220×460×145 mm, but catalogue C/C0 ratings differ between executions (2900/3650 vs 2510/3650 kN) and the NUH flange/ring configuration differs — envelope match, not a load-rating equivalent. |
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 NUH2344-ECMH-PEX model number is decoded
SKF NUH 2344 ECMH/PEX is a high-capacity cylindrical roller bearing sized 220×460×145 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.2. Structurally, the NUH design has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring. In arrangement terms it is the locating partner in paired cross-locating arrangements for heavily loaded shafts, locating axially in one direction. The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. The radial section height is 120.0 mm and the catalogue mass 116000 g; at 2900 kN dynamic rating this is roughly 13.18 kN of C per millimetre of bore before application factors. Mounting: typically paired with the matching NCF ECJB non-locating bearing on the same shaft; observe the catalogue shoulder and fillet data for the large inner ring. A 220 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates. 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 2900 kN / C0 3650 kN here) because the roller complement and internal profiling differ from the standard execution. Treat NUH2344-ECMH-PEX as a separate service part: do not substitute the standard NUH 2344 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
- 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
- false brinelling on standby machines exposed to external vibration
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 NUH 2344 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.
- 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 460 mm raceway.
- The 2900/3650 kN ratings are SKF catalogue 17000 (2018) values for the ECMH/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 NUH2344-ECMH-PEX?
SKF NUH 2344 ECMH/PEX is a high-capacity cylindrical roller bearing with 220 mm bore, 460 mm OD and 145 mm width per ISO 15. SKF lists C 2900 kN, C0 3650 kN, Pu 335 kN, reference speed 1,400 r/min and limiting speed 1,700 r/min, mass about 116000 g.
What does the NUH designation and ECMH/PEX suffix mean?
The ECMH suffix denotes the high-capacity execution with a machined brass cage; the /PEX variant is the pinion-shaft special build. Structurally this execution has a high-capacity NJ-type execution whose displaced cage bars make room for additional rollers, with two integral flanges on the inner ring.
Can NUH2344-ECMH-PEX take axial load and locate the shaft?
In one direction, as the locating member of a high-capacity pair; the matching NCF ECJB bearing floats. It is not a general-purpose axial bearing.
How does NUH2344-ECMH-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.