NU1056-ML bearing: complete specifications & equivalents
The NU1056-ML is a ISO 15 radial bearing sized 280 x 420 x 65 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | SKF |
| Bore diameter d | 280 mm |
| Outer diameter D | 420 mm |
| Width B | 65 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | brass |
| Basic dynamic load rating C | 660 kN |
| Basic static load rating C0 | 1060 kN |
| Fatigue load limit Pu | 102 kN |
| Reference speed (thermal) | 1700 rpm |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 31000 g |
| Manufacturer designation | SKF NU 1056 ML |
| 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 & NU1000-series range
| Bore d | 11.024 in |
|---|---|
| Outer diameter D | 16.535 in |
| Width B | 2.559 in |
| ISO bore code | 56 |
| Radial section height (D−d)/2 | 70 mm |
| Smallest bore in NU1000-series | 25 mm |
| Largest outer diameter in NU1000-series | 1090 mm |
| Width range across NU1000-series | 12–150 mm |
| Bore position in NU1000-series (smallest first) | 31 of 45 |
| Bore above smallest NU1000-series size | 255 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the NU1056-ML model number is decoded
SKF NU 1056 ML is a single-row caged cylindrical roller bearing sized 280×420×65 mm — a dimension series 10 (extra-slim OD, normal width), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. The NU configuration means two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable; functionally the bearing is non-locating: the inner ring assembly can float axially in both directions and the bearing cannot support axial load. The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. The one-piece machined brass cage is reflected in the published speeds and temperature limits. Load-per-bore for the 280 mm seat is about 2.36 kN/mm, typical of dimension series 10 (extra-slim OD, normal width); use C0 1060 kN for static checks such as crane hook blocks standing under load. Fit practice for NU1056-ML: fit the inner ring and roller assembly onto the shaft and the outer ring into the housing independently; thermal expansion is absorbed by axial float, so do not trap the inner ring between shaft shoulders. 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
- 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
- smearing (microwelding) on roller surfaces during skid starts with insufficient minimum load
Selection pitfalls — read before you substitute
- Do not use a NU bearing where axial load must be carried — the design carries radial load only
- The dimension series 10 (extra-slim OD, normal width) envelope is shared with the N/NU/NJ/NUP executions of 1056, but flange configuration and axial-locating behaviour differ — quote the full SKF NU 1056 ML 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 420 mm raceway.
- Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
- The 660/1060 kN ratings are SKF catalogue 17000 (2018) values for the ML 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 NU1056-ML?
SKF NU 1056 ML is a single-row caged cylindrical roller bearing with 280 mm bore, 420 mm OD and 65 mm width per ISO 15. SKF lists C 660 kN, C0 1060 kN, Pu 102 kN, reference speed 1,700 r/min and limiting speed 2,600 r/min, mass about 31000 g.
What does the NU designation and ML suffix mean?
The ML suffix marks the basic (non-E) execution with a machined brass cage, the standard choice for the larger and earlier-design sizes. Structurally this execution has two integral flanges on the outer ring and no flanges on the inner ring, so the inner ring together with the roller set is separable.
Can NU1056-ML take axial load and locate the shaft?
No — the inner ring has no flanges, so the NU bearing is non-locating and carries radial load only; use NJ (one direction), NUP (both directions) or a paired thrust bearing for axial duty.
How does NU1056-ML 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.