N1056 bearing: complete specifications & equivalents
The N1056 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 | NTN |
| 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 | steel |
| Basic dynamic load rating C | 730 kN |
| Basic static load rating C0 | 1050 kN |
| Fatigue load limit Pu | 88 kN |
| Limiting speed (mechanical) | 1500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 30400 g |
| Manufacturer designation | NTN N1056 |
| Standard | ISO 15 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & N1000-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 N1000-series | 25 mm |
| Largest outer diameter in N1000-series | 720 mm |
| Width range across N1000-series | 12–100 mm |
| Bore position in N1000-series (smallest first) | 31 of 42 |
| Bore above smallest N1000-series size | 255 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| N1056 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 N1056 model number is decoded
N1056 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 730 kN dynamic rating in the 280 mm bore. Reading the code: N for the separable-outer-ring type, then the ISO 15 diameter/width series and the bore code — ×5 = 280 mm (00–03 use the 10/12/15/17 exception table). Minimum radial load matters: an unloaded N1056 at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. Equivalent-load planning treats N1056 as a pure radial bearing: keep P below 730 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. Mount the separable inner ring + roller assembly on the shaft first and slide the outer ring into the housing; never press the outer ring through the rollers of N1056.
Typical equipment & failure modes
Common applications
- offshore drawworks and winch drums
- heavy press and large gearbox main shafts
- rolling-mill work-roll and backup-roll positions
- large turbine and generator rotor bearings
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- cage wear accelerated when the EA high-capacity roller complement runs continuously above its thermal balance
- roller-end and raceway scoring from inadequate oil flow under heavy radial load
- hard-particle indentation of raceways in unfiltered oil or open arrangements
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
Selection pitfalls — read before you substitute
- At 280 mm bore, oil-lubricated arrangements toward 1,800 r/min need positive flow and drain design; the 30400 g N1056 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Wide (22/23) and light (10/49) executions at 280 mm bore share bore but not OD/width; check the full N1000 series code before substituting, because housing and shoulder geometry will not interchange.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded N1056 skids at 1,500 r/min and fails by smearing long before L10 fatigue.
- Grease limiting speed 1,500 r/min and oil 1,800 r/min are different limits for N1056: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- Do not replace N1056 with a deep-groove ball bearing on rating alone: line contact gives 730 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- The 730/1050 kN ratings, 88 kN Pu and 30400 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for N1056 (standard execution); other makes sharing the ISO 15 envelope revise internal geometry without changing the order number, so keep the 2203E reference with the specification for critical drives.
Frequently asked questions
What are the dimensions and catalogue data of N1056?
N1056 is an NTN N single-row cylindrical roller bearing to ISO 15: 280 mm bore, 420 mm OD and 65 mm width (11.024 × 16.535 × 2.559 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 730 kN, C0 1050 kN, Pu 88 kN, grease limiting speed 1,500 r/min, oil 1,800 r/min, mass about 30400 g. It is open, with a pressed sheet-steel cage.
What is the difference between NU, NJ, NUP, N and NF cylindrical roller bearings?
The prefix states the rib arrangement: NU has two outer-ring ribs and a ribless inner ring (float, no axial load); NJ adds ribs for one-direction location; NUP adds a loose L-ring to locate both directions; N has two inner-ring ribs and a separable outer ring; NF has one rib per ring for one-direction guidance. N1056 is two integral ribs on the inner ring and a ribless separable outer ring — equivalent float behaviour with the separable ring on the housing side.
What do the EA, E and ＊ suffixes mean on NTN cylindrical roller bearings?
EA is NTN's high-capacity design with a pressed sheet-steel cage and optimised roller complement in the same ISO 15 envelope; E marks the high-capacity design at the larger bores; the ＊ symbol printed before the code in the NTN catalogue marks the ULTAGE new-generation specification and is not typed as part of the order number. N1056 is supplied in the standard open execution shown in the table.
Can N1056 take axial load and locate a shaft?
the N design is non-locating like NU but floats with the separable outer ring in the housing. Provide axial location with an adjacent locating bearing (angular-contact, deep-groove or a paired NJ/NUP set).
What do Fw and Ew mean for N1056?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 316 mm, Ew 384 mm. The nominal bore/OD remain 280/420 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,500 r/min grease / 1,800 r/min oil.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.