NU2211-NTN bearing: complete specifications & equivalents
The NU2211-NTN is a ISO 15 radial bearing sized 55 x 100 x 25 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 55 mm |
| Outer diameter D | 100 mm |
| Width B | 25 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 83.5 kN |
| Basic static load rating C0 | 87 kN |
| Fatigue load limit Pu | 10.6 kN |
| Limiting speed (mechanical) | 6300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 758 g |
| Manufacturer designation | NTN NU2211 |
| 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 & NU2200-series range
| Bore d | 2.165 in |
|---|---|
| Outer diameter D | 3.937 in |
| Width B | 0.984 in |
| ISO bore code | 11 |
| Radial section height (D−d)/2 | 22.5 mm |
| Smallest bore in NU2200-series | 17 mm |
| Largest outer diameter in NU2200-series | 1030 mm |
| Width range across NU2200-series | 16–272 mm |
| Bore position in NU2200-series (smallest first) | 9 of 39 |
| Bore above smallest NU2200-series size | 38 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NU2211 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 55×100×25 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 NU2211-NTN model number is decoded
The NTN order number NU2211 denotes a 55×100×25 mm (2.165 × 3.937 × 0.984 in) cylindrical roller bearing in the NU2200 family, a pressed sheet-steel cage. On the NTN nameplate NU states which ring carries the ribs, which determines whether NU2211 floats or locates; the numeric remainder is the ISO 15 series and 55 mm bore reference, not a fit or clearance instruction. The 22.5 mm radial section ((100−55)/2) frames the roller complement; capacity per millimetre of bore is about 1.5 kN/mm before application factors. With the inner ring rotating, catalogue practice is a k5/m5 shaft seat and an H7/H6 housing; the outer ring must remain free to creep slightly axially in non-locating NU arrangements. After mounting verify the outer ring slides axially by hand at ambient temperature; a stuck float ring in a NU2211 non-locating position preloads the bearing when the shaft grows.
Typical equipment & failure modes
Common applications
- medium electric-motor and generator shafts
- pump and compressor crankshafts and rotors
- machine-tool gearbox and spindle radial sets
- material-handling drum and wheel shafts
Known failure patterns
- inner-ring raceway spalling from overload in the line-contact Hertzian zone
- pressed-steel cage pocket wear when rollers skid at light load or too-thin lubricant
- micro-pitting when the EHL film falls below the composite roughness at high specific load
- false brinelling on standby machines exposed to external vibration
- fretting corrosion on a loose rotating shaft seat
Selection pitfalls — read before you substitute
- On this 55 mm bore, shaft thermal growth can preload the inner ring if the fit is too tight; verify residual interference at temperature and confirm the float ring still slides after mounting NU2211.
- The NU rib arrangement is not interchangeable with another prefix on the same 55 mm seat: outer ring ribbed, inner ring ribless. Swapping NU for NJ changes axial location behaviour even though the 100×25 mm envelope matches.
- Wide (22/23) and light (10/49) executions at 55 mm bore share bore but not OD/width; check the full NU2200 series code before substituting, because housing and shoulder geometry will not interchange.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 100 mm race brinells and releases as vibration within hours.
- The 22.5 mm section at 55 mm bore leaves a narrow oil path; with the standard cage the relubrication groove and oil-level design must keep grease from churning in the 25 mm-wide cavity.
- The 83.5/87 kN ratings, 10.6 kN Pu and 758 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NU2211 (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 NU2211?
NU2211 is an NTN NU single-row cylindrical roller bearing to ISO 15: 55 mm bore, 100 mm OD and 25 mm width (2.165 × 3.937 × 0.984 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 83.5 kN, C0 87 kN, Pu 10.6 kN, grease limiting speed 6,300 r/min, oil 7,400 r/min, mass about 758 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. NU2211 is two integral ribs on the outer ring and a ribless, separable inner ring — a non-locating bearing that lets the shaft float axially.
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. NU2211 is listed among the ＊ ULTAGE-marked executions in 2203E.
Can NU2211 take axial load and locate a shaft?
the NU design carries no axial load and floats axially on both sides. 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 NU2211?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 66.5 mm, Ew 88.5 mm. The nominal bore/OD remain 55/100 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 6,300 r/min grease / 7,400 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.