NUP2228-ECML bearing: complete specifications & equivalents
The NUP2228-ECML is a ISO 15 radial bearing sized 140 x 250 x 68 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 140 mm |
| Outer diameter D | 250 mm |
| Width B | 68 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 655 kN |
| Basic static load rating C0 | 830 kN |
| Fatigue load limit Pu | 93 kN |
| Reference speed (thermal) | 2800 rpm |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 15500 g |
| Manufacturer designation | SKF NUP 2228 ECML |
| 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 & NUP2200-series range
| Bore d | 5.512 in |
|---|---|
| Outer diameter D | 9.843 in |
| Width B | 2.677 in |
| ISO bore code | 28 |
| Radial section height (D−d)/2 | 55 mm |
| Smallest bore in NUP2200-series | 17 mm |
| Largest outer diameter in NUP2200-series | 250 mm |
| Width range across NUP2200-series | 16–68 mm |
| Bore position in NUP2200-series (smallest first) | 21 of 21 |
| Bore above smallest NUP2200-series size | 123 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ2228-ECML | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NU2228-ECML | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 140×250×68 mm and equivalent catalogue ratings; the NU 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 NUP2228-ECML model number is decoded
For a 140 mm shaft, SKF lists NUP2228-ECML as single-row caged cylindrical roller: 250 mm OD, 68 mm wide, Pu 93 kN, the catalogue lists 2,800 r/min thermal reference speed and 4,800 r/min mechanical limiting speed. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECML 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. Load-per-bore for the 140 mm seat is about 4.68 kN/mm, typical of dimension series 22 (light-section, wide); use C0 830 kN for static checks such as crane hook blocks standing under load. Fit practice for NUP2228-ECML: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. Single-row cylindrical rollers tolerate only about 3–4 minutes of arc misalignment, so verify shaft and housing alignment.
Typical equipment & failure modes
Common applications
- offshore drawworks shafts
- large rolling-mill drive trains
- marine propulsion line shafts
- heavy turbogenerator rotor supports
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
- surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load
- edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit
- 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
- Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing
- The dimension series 22 (light-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2228, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2228 ECML and do not substitute rib styles without checking the shaft locating scheme.
- Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
- Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
- The 655/830 kN ratings are SKF catalogue 17000 (2018) values for the ECML 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 NUP2228-ECML?
SKF NUP 2228 ECML is a single-row caged cylindrical roller bearing with 140 mm bore, 250 mm OD and 68 mm width per ISO 15. SKF lists C 655 kN, C0 830 kN, Pu 93 kN, reference speed 2,800 r/min and limiting speed 4,800 r/min, mass about 15500 g.
What does the NUP designation and ECML suffix mean?
The ECML 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 outer ring plus one integral flange and one loose flange ring on the inner ring.
Can NUP2228-ECML take axial load and locate the shaft?
Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance.
How does NUP2228-ECML 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.