NJ2306EA bearing: complete specifications & equivalents
The NJ2306EA is a ISO 15 radial bearing sized 30 x 72 x 27 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 30 mm |
| Outer diameter D | 72 mm |
| Width B | 27 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 88 kN |
| Basic static load rating C0 | 77.5 kN |
| Fatigue load limit Pu | 9.45 kN |
| Limiting speed (mechanical) | 8300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 526 g |
| Manufacturer designation | NTN NJ2306EA |
| 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 & NJ2300-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 2.835 in |
| Width B | 1.063 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 21 mm |
| Smallest bore in NJ2300-series | 20 mm |
| Largest outer diameter in NJ2300-series | 580 mm |
| Width range across NJ2300-series | 21–175 mm |
| Bore position in NJ2300-series (smallest first) | 3 of 31 |
| Bore above smallest NJ2300-series size | 10 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ2306EA | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the 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 NJ2306EA model number is decoded
NJ2306EA belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E, under the ＊ ULTAGE new-generation specification: line-contact rollers between ground raceways for a 88 kN dynamic rating in the 30 mm bore. The leading NJ defines the rib arrangement (inner ring two ribs + one outer rib); the dimension-series digits and the two-digit bore code resolve to 30 mm, with 72 mm OD and 27 mm width from the ISO 15 general plan. With C 88 kN and C0 77.5 kN (C0/C ≈ 0.88) the bearing is proportioned for heavy radial load; the NJ design accepts axial load in one direction and provides one-way shaft location. Equivalent-load planning treats NJ2306EA as a pure radial bearing: keep P below 88 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. Keep the open bearing wrapped until fitting: the line-contact raceways of the 30 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.
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
- cage wear accelerated when the EA high-capacity roller complement runs continuously above its thermal balance
- micro-pitting when the EHL film falls below the composite roughness at high specific load
- false brinelling on standby machines exposed to external vibration
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
Selection pitfalls — read before you substitute
- On this 30 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 NJ2306EA.
- Grease limiting speed 8,300 r/min and oil 11,600 r/min are different limits for NJ2306EA: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 72 mm race brinells and releases as vibration within hours.
- Wide (22/23) and light (10/49) executions at 30 mm bore share bore but not OD/width; check the full NJ2300 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 NJ2306EA skids at 8,300 r/min and fails by smearing long before L10 fatigue.
- The 88/77.5 kN ratings, 9.45 kN Pu and 526 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ2306EA (EA pressed-steel-cage 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 NJ2306EA?
NJ2306EA is an NTN NJ single-row cylindrical roller bearing to ISO 15: 30 mm bore, 72 mm OD and 27 mm width (1.181 × 2.835 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 88 kN, C0 77.5 kN, Pu 9.45 kN, grease limiting speed 8,300 r/min, oil 11,600 r/min, mass about 526 g. It is open, with the EA high-capacity 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. NJ2306EA is two integral ribs on the inner ring and one rib on the outer ring — it locates the shaft in one axial direction.
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. This page's bearing carries the EA pressed-steel-cage execution.
Can NJ2306EA take axial load and locate a shaft?
the NJ design accepts axial load in one direction and provides one-way shaft location. For two-direction location use an NUP execution or an NJ pair with loose rib rings.
What do Fw and Ew mean for NJ2306EA?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 40.5 mm, Ew 62.5 mm. The nominal bore/OD remain 30/72 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 8,300 r/min grease / 11,600 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.