NF2304EA bearing: complete specifications & equivalents
The NF2304EA is a ISO 15 radial bearing sized 20 x 52 x 21 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 20 mm |
| Outer diameter D | 52 mm |
| Width B | 21 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 49.5 kN |
| Basic static load rating C0 | 39 kN |
| Fatigue load limit Pu | 4.75 kN |
| Limiting speed (mechanical) | 12000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 212 g |
| Manufacturer designation | NTN NF2304EA |
| 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 & NF2300-series range
| Bore d | 0.787 in |
|---|---|
| Outer diameter D | 2.047 in |
| Width B | 0.827 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 16 mm |
| Smallest bore in NF2300-series | 20 mm |
| Largest outer diameter in NF2300-series | 170 mm |
| Width range across NF2300-series | 21–58 mm |
| Bore position in NF2300-series (smallest first) | 1 of 13 |
| Bore above smallest NF2300-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF2304EA | 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 NF2304EA model number is decoded
NTN lists NF2304EA on the 20×52 mm envelope, 21 mm wide: a line-contact radial bearing with the EA high-capacity pressed sheet-steel cage and a grease limiting speed of 12,000 r/min. Digit by digit, NF2304EA reads as NF (one rib on each ring), ISO 15 series, and bore 20 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. Line contact between rollers and raceways gives NF2304EA high radial capacity but no tolerance for misalignment: beyond roughly 3–4 arc-minutes the roller ends edge-load and fatigue accelerates. Selection arithmetic: Pu 4.75 kN is the fatigue load limit feeding the adjusted-life equation, and the C0/C ratio of 0.79 (39/49.5 kN) shows the high-static-capacity proportioning of this 20 mm bore. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 20 mm shaft.
Typical equipment & failure modes
Common applications
- agricultural PTO and implement gear shafts
- small conveyor and fan rotor positions
- small electric-motor armature shafts
- light gearbox layshaft and pinion positions
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
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- false brinelling on standby machines exposed to external vibration
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- Small 20 mm-bore cylindrical rollers are skid-sensitive: ensure the radial load exceeds the minimum-load floor at operating speed, or the NF2304EA rollers smear even with correct grease.
- Grease limiting speed 12,000 r/min and oil 16,800 r/min are different limits for NF2304EA: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- The 21 mm width and abutment faces must be square to the axis; a tilted spacer concentrates load across the roller set and shows as uneven raceway polish on the 20 mm inner ring.
- The 16.0 mm section at 20 mm bore leaves a narrow oil path; with the EA pressed-steel-cage cage the relubrication groove and oil-level design must keep grease from churning in the 21 mm-wide cavity.
- Wide (22/23) and light (10/49) executions at 20 mm bore share bore but not OD/width; check the full NF2300 series code before substituting, because housing and shoulder geometry will not interchange.
- The 49.5/39 kN ratings, 4.75 kN Pu and 212 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF2304EA (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 NF2304EA?
NF2304EA is an NTN NF single-row cylindrical roller bearing to ISO 15: 20 mm bore, 52 mm OD and 21 mm width (0.787 × 2.047 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 49.5 kN, C0 39 kN, Pu 4.75 kN, grease limiting speed 12,000 r/min, oil 16,800 r/min, mass about 212 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. NF2304EA is one integral rib on each ring — separable inner ring with single-direction axial guidance and a defined shaft position.
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 NF2304EA take axial load and locate a shaft?
the NF design gives one-direction axial guidance via its single outer-ring rib. The loose rib ring still only suits light/short-duration axial guidance; heavy thrust belongs to a dedicated thrust bearing.
What do Fw and Ew mean for NF2304EA?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 27.5 mm, Ew 45.5 mm. The nominal bore/OD remain 20/52 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 12,000 r/min grease / 16,800 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.