NU214 bearing: complete specifications & equivalents
The NU214 is a ISO 15 radial bearing sized 70 x 125 x 24 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 70 mm |
| Outer diameter D | 125 mm |
| Width B | 24 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | polymer (PA66 glass-fibre reinforced) |
| Basic dynamic load rating C | 137 kN |
| Basic static load rating C0 | 137 kN |
| Fatigue load limit Pu | 18 kN |
| Reference speed (thermal) | 6000 rpm |
| Limiting speed (mechanical) | 6300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1150 g |
| Manufacturer designation | NU 214 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 & NU200-series range
| Bore d | 2.756 in |
|---|---|
| Outer diameter D | 4.921 in |
| Width B | 0.945 in |
| ISO bore code | 14 |
| Radial section height (D−d)/2 | 27.5 mm |
| Smallest bore in NU200-series | 15 mm |
| Largest outer diameter in NU200-series | 580 mm |
| Width range across NU200-series | 11–92 mm |
| Bore position in NU200-series (smallest first) | 13 of 36 |
| Bore above smallest NU200-series size | 55 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NU214-NTN | NTN | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 70×125×24 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
| 6214 | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Identical envelope but a different bearing type — confirm load and speed suitability before substitution. |
| 6214-2RS | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Identical envelope but a different bearing type — confirm load and speed suitability before substitution. |
| 6214-ZZ | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Identical envelope but a different bearing type — confirm load and speed suitability before substitution. |
| N214-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 boundary envelope and equivalent catalogue ratings; SKF N 214 ECP is a different execution with its own cage/flange configuration. |
| NJ214-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 boundary envelope and equivalent catalogue ratings; SKF NJ 214 ECP is a different execution with its own cage/flange configuration. |
| NUP214-ECP | SKF | full Dimensions and internal design equivalent — standard interchange. | Same ISO 15 boundary envelope and equivalent catalogue ratings; SKF NUP 214 ECP is a different execution with its own cage/flange configuration. |
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 NU214 model number is decoded
The NU 214 ECP is a 70×125×24 mm single-row cylindrical roller bearing — the standard entry in the NU200 series, with separable inner ring and roller assembly for easy mounting. Digit by digit, NU214 reads as bearing type NU (single-row, inner ring separable), standard series 2, and bore reference 14 resolving to 70 mm; 125 mm OD and 24 mm width are the matching ISO 15 boundary values. The SKF catalogue adds the ECP suffix for the standard glass-fibre reinforced polyamide cage; ECJ (pressed steel) and ECM (machined brass) are alternative executions with different speed and temperature ratings. Catalogue mass 1150 g for the 70×125×24 mm open execution covers the polymer cage and standard roller complement; steel or brass cage variants differ slightly in mass and carry their own order numbers. Mount the separable inner ring + roller assembly onto the shaft first, then slide the outer ring into the housing; the NU design has no outer-ring ribs, so axial location of the shaft must be provided by adjacent components or a second bearing.
Typical equipment & failure modes
Common applications
- cement-kiln support-roller shafts
- wind-turbine gearbox intermediate shafts
- marine propulsion gearbox shafts
- heavy industrial gearbox 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 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
- brinelling from static overload or impact during handling and mounting
Selection pitfalls — read before you substitute
- Mount the 70 mm bore NU214 by induction heating of the inner ring (max 120 °C — the polymer cage sets the ceiling, not the steel); driving it home through the rollers brinells the raceway.
- The NU200 series at 70 mm bore (125×24 mm) is the standard-section cylindrical roller envelope; stepping to a wide-section 22/23 variant changes OD, width and heat generation — it is not a drop-in swap when the housing and speed are fixed.
- The 1150 g mass and 24 mm width mean abutment faces must be square to the axis within the bearing's own P0 tolerance; a tilted spacer tilts the outer ring and concentrates load on one roller row of NU214.
- Catalogue reference speed and limiting speed are different limits: the 6,000 r/min reference is a thermal criterion under load, while the 6,300 r/min limiting value is the mechanical ceiling — observe both.
- The 137/137 kN ratings are SKF catalogue 17000 values for the ECP polymer-cage execution; SKF can revise internal geometry without changing the order number, so keep the catalogue version (PUB BU/P1 17000/1 EN, 2018) with the specification and re-verify for critical drives.
- SKF lists several executions of NU214 (ECP polymer cage, ECJ pressed steel, ECM machined brass); they are not interchangeable order numbers — quote the full NU 214 ECP designation when purchasing and match the execution to the speed and temperature requirements.
Frequently asked questions
What are the dimensions and catalogue data of NU214?
The NU 214 ECP is a single-row cylindrical roller bearing with 70 mm bore, 125 mm outer diameter and 24 mm width (2.756 × 4.921 × 0.945 in) per ISO 15. From SKF catalogue PUB BU/P1 17000: basic dynamic load rating C 137 kN, C0 137 kN, fatigue load limit Pu 18 kN, reference speed 6,000 r/min, limiting speed 6,300 r/min, mass about 1150 g. It is an open, separable bearing with a glass-fibre reinforced polyamide cage.
How does the NU214 bore code work?
The last two digits of NU214 are bore code 14, so 14 × 5 = 70 mm bore. The 125 mm OD and 24 mm width come from the ISO 15 dimension-series plan, shared with other cylindrical bearings of the same code.
What does the ECP suffix mean on NU214?
ECP stands for a glass-fibre reinforced polyamide cage (PA66), the SKF standard for this size. Alternative executions include ECJ (pressed steel cage) and ECM (machined brass cage), which have different speed and temperature ratings and are separate order numbers.
Can NU214 take axial load?
No — the NU design has no ribs on the outer ring and cannot support axial load in either direction. It is intended for pure radial load with axial location provided by adjacent components. If axial location is required, consider NJ (one-direction) or NUP (two-direction) variants, or pair the NU bearing with a thrust or angular-contact bearing.
How does NU214 compare with a ball bearing of the same bore?
A cylindrical roller bearing has line contact and much higher radial capacity than a ball bearing of the same bore, but it cannot take axial load in the NU design and is sensitive to misalignment (≈ 3–4 minutes of arc). Speed limits are generally lower than deep-groove ball bearings. A ball bearing cannot be dropped into a pure radial cylindrical-roller position without re-checking life and deflection, and vice versa.
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.