NUP322-ECP bearing: complete specifications & equivalents
The NUP322-ECP is a ISO 15 radial bearing sized 110 x 240 x 50 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 110 mm |
| Outer diameter D | 240 mm |
| Width B | 50 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 530 kN |
| Basic static load rating C0 | 540 kN |
| Fatigue load limit Pu | 61 kN |
| Reference speed (thermal) | 3000 rpm |
| Limiting speed (mechanical) | 3400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 10500 g |
| Manufacturer designation | SKF NUP 322 ECP |
| 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 & NUP300-series range
| Bore d | 4.331 in |
|---|---|
| Outer diameter D | 9.449 in |
| Width B | 1.969 in |
| ISO bore code | 22 |
| Radial section height (D−d)/2 | 65 mm |
| Smallest bore in NUP300-series | 20 mm |
| Largest outer diameter in NUP300-series | 300 mm |
| Width range across NUP300-series | 15–62 mm |
| Bore position in NUP300-series (smallest first) | 18 of 21 |
| Bore above smallest NUP300-series size | 90 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| N322-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the N execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NJ322-ECJ | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 110×240×50 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical. |
| NU322-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 envelope 110×240×50 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 NUP322-ECP model number is decoded
In SKF catalogue PUB BU/P1 17000, SKF NUP 322 ECP denotes a single-row caged cylindrical roller bearing on the ISO 15 110×240×50 mm envelope, dimension series 3 (medium-section ISO 15 envelope), with catalogue mass 10500 g. The NUP configuration means two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring; functionally the bearing is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Speed planning for NUP322-ECP: the catalogue lists 3,000 r/min thermal reference speed and 3,400 r/min mechanical limiting speed. The mass entry 10500 g covers the complete catalogue execution. Assembly note: 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. Heat steel rings inductively to max 120 °C — the PA66 cage sets the ceiling.
Typical equipment & failure modes
Common applications
- paper-machine press rolls
- cement-plant conveyor drives
- heavy gearbox and pinion shafts
- large pump and blower rotors
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
- polymer cage softening above 120 °C
- 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
- edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit
- rolling-contact fatigue spalling after the rated L10 life is exceeded
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 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 322, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 322 ECP 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 240 mm raceway.
- Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
- The 530/540 kN ratings are SKF catalogue 17000 (2018) values for the ECP 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 NUP322-ECP?
SKF NUP 322 ECP is a single-row caged cylindrical roller bearing with 110 mm bore, 240 mm OD and 50 mm width per ISO 15. SKF lists C 530 kN, C0 540 kN, Pu 61 kN, reference speed 3,000 r/min and limiting speed 3,400 r/min, mass about 10500 g.
What does the NUP designation and ECP suffix mean?
The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. 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 NUP322-ECP 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 NUP322-ECP 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.