N326-ECM bearing: complete specifications & equivalents
The N326-ECM is a ISO 15 radial bearing sized 130 x 280 x 58 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 130 mm |
| Outer diameter D | 280 mm |
| Width B | 58 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 720 kN |
| Basic static load rating C0 | 750 kN |
| Fatigue load limit Pu | 81.5 kN |
| Reference speed (thermal) | 2400 rpm |
| Limiting speed (mechanical) | 3000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 18000 g |
| Manufacturer designation | SKF N 326 ECM |
| Standard | ISO 15 |
| Catalog version | SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings |
| Last verified | 2026-09-26 |
Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row 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. 6.1 single-row 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 & N300-series range
| Bore d | 5.118 in |
|---|---|
| Outer diameter D | 11.024 in |
| Width B | 2.283 in |
| ISO bore code | 26 |
| Radial section height (D−d)/2 | 75 mm |
| Smallest bore in N300-series | 17 mm |
| Largest outer diameter in N300-series | 280 mm |
| Width range across N300-series | 14–58 mm |
| Bore position in N300-series (smallest first) | 22 of 22 |
| Bore above smallest N300-series size | 113 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ326-ECJ | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NU326-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NUP326-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 130×280×58 mm and equivalent catalogue ratings; the NUP 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 N326-ECM model number is decoded
N326-ECM is the 130 mm bore entry in the N300 range: a 130×280×58 mm single-row caged cylindrical roller bearing with a one-piece machined brass cage, rated C 720 kN / C0 750 kN. The N configuration means two integral flanges on the inner ring and no flanges on the outer ring, so the plain outer ring is the separable part; functionally the bearing is non-locating: the outer ring can displace axially in both directions and the bearing carries radial load only. The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Speed planning for N326-ECM: the catalogue lists 2,400 r/min thermal reference speed and 3,000 r/min mechanical limiting speed. The mass entry 18000 g covers the complete catalogue execution. Mounting: the outer ring slides in its housing seat; provide axial retention for the outer ring only if the application requires it, and let it float to absorb shaft expansion. A 130 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.
Typical equipment & failure modes
Common applications
- mining hoist and winder shafts
- offshore drawworks shafts
- large rolling-mill drive trains
- marine propulsion line 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
- cage pocket wear from roller skew at light 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
- edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- Do not use a N bearing where axial load must be carried — the design carries radial load only
- The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 326, but flange configuration and axial-locating behaviour differ — quote the full SKF N 326 ECM and do not substitute rib styles without checking the shaft locating scheme.
- Press-fit force goes through ring faces only; driving a ring home through the rollers brinells the 280 mm raceway.
- Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 58 mm-wide ring and concentrates load.
- The 720/750 kN ratings are SKF catalogue 17000 (2018) values for the ECM 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 N326-ECM?
SKF N 326 ECM is a single-row caged cylindrical roller bearing with 130 mm bore, 280 mm OD and 58 mm width per ISO 15. SKF lists C 720 kN, C0 750 kN, Pu 81.5 kN, reference speed 2,400 r/min and limiting speed 3,000 r/min, mass about 18000 g.
What does the N designation and ECM suffix mean?
The ECM suffix denotes the E-design execution with a one-piece machined brass cage for higher-temperature and higher-speed continuous duty. Structurally this execution has two integral flanges on the inner ring and no flanges on the outer ring, so the plain outer ring is the separable part.
Can N326-ECM take axial load and locate the shaft?
No — the plain outer ring has no flanges, so the N bearing floats axially and is for radial load; locate the shaft with a separate bearing.
How does N326-ECM 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. 6.1 single-row cylindrical roller bearings on 2026-09-26. Read our editorial & correction policy.