NU2248 bearing: complete specifications & equivalents
The NU2248 is a ISO 15 radial bearing sized 240 x 440 x 120 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 240 mm |
| Outer diameter D | 440 mm |
| Width B | 120 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1590 kN |
| Basic static load rating C0 | 2320 kN |
| Fatigue load limit Pu | 196 kN |
| Limiting speed (mechanical) | 1300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 78400 g |
| Manufacturer designation | NTN NU2248 |
| 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 | 9.449 in |
|---|---|
| Outer diameter D | 17.323 in |
| Width B | 4.724 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 100 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) | 30 of 39 |
| Bore above smallest NU2200-series size | 223 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NU2248-MA | SKF | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 NU2248 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, NU2248 appears as a 240 mm bore single-row cylindrical roller bearing (1590 kN C / 2320 kN C0) with a pressed sheet-steel cage, listed to the ISO 15 boundary plan. On the NTN nameplate NU states which ring carries the ribs, which determines whether NU2248 floats or locates; the numeric remainder is the ISO 15 series and 240 mm bore reference, not a fit or clearance instruction. At 1,600 r/min with oil versus 1,300 r/min with grease (a 300 r/min band), lubrication choice for NU2248 is a thermal decision, not just a sealing one. Speed ratio check: limiting 1,300 r/min is .81 of the 1,600 r/min oil value for NU2248; grease-churn heating closes that gap as fill quantity rises. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 240 mm shaft.
Typical equipment & failure modes
Common applications
- heavy press and large gearbox main shafts
- rolling-mill work-roll and backup-roll positions
- large turbine and generator rotor bearings
- wind-turbine gearbox planet and rotor shafts
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
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- At 240 mm bore, oil-lubricated arrangements toward 1,600 r/min need positive flow and drain design; the 78400 g NU2248 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- If the shaft must be located both ways, do not use NU2248 alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 1590/2320 kN pair here belongs to NU2248 as printed, not to the bare size.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 440 mm race brinells and releases as vibration within hours.
- Grease limiting speed 1,300 r/min and oil 1,600 r/min are different limits for NU2248: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- The 1590/2320 kN ratings, 196 kN Pu and 78400 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NU2248 (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 NU2248?
NU2248 is an NTN NU single-row cylindrical roller bearing to ISO 15: 240 mm bore, 440 mm OD and 120 mm width (9.449 × 17.323 × 4.724 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1590 kN, C0 2320 kN, Pu 196 kN, grease limiting speed 1,300 r/min, oil 1,600 r/min, mass about 78400 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. NU2248 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. NU2248 is supplied in the standard open execution shown in the table.
Can NU2248 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 NU2248?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 295 mm, Ew 385 mm. The nominal bore/OD remain 240/440 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,300 r/min grease / 1,600 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.