NF224 bearing: complete specifications & equivalents
The NF224 is a ISO 15 radial bearing sized 120 x 215 x 40 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 120 mm |
| Outer diameter D | 215 mm |
| Width B | 40 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 288 kN |
| Basic static load rating C0 | 320 kN |
| Fatigue load limit Pu | 33.5 kN |
| Limiting speed (mechanical) | 3200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5460 g |
| Manufacturer designation | NTN NF224 |
| 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 & NF200-series range
| Bore d | 4.724 in |
|---|---|
| Outer diameter D | 8.465 in |
| Width B | 1.575 in |
| ISO bore code | 24 |
| Radial section height (D−d)/2 | 47.5 mm |
| Smallest bore in NF200-series | 20 mm |
| Largest outer diameter in NF200-series | 580 mm |
| Width range across NF200-series | 14–92 mm |
| Bore position in NF200-series (smallest first) | 20 of 34 |
| Bore above smallest NF200-series size | 100 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF224 | 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 NF224 model number is decoded
NF224 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 288 kN dynamic rating in the 120 mm bore. The leading NF defines the rib arrangement (one rib on each ring); the dimension-series digits and the two-digit bore code resolve to 120 mm, with 215 mm OD and 40 mm width from the ISO 15 general plan. With C 288 kN and C0 320 kN (C0/C ≈ 1.11) the bearing is proportioned for heavy radial load; the NF design gives one-direction axial guidance via its single outer-ring rib. Rating life at 288 kN C assumes clean oil and adequate film; the 33.5 kN Pu floor means contamination derating — not the C rating alone — governs adjusted life in dusty gearboxes. After mounting verify the outer ring slides axially by hand at ambient temperature; a stuck float ring in a NF224 non-locating position preloads the bearing when the shaft grows.
Typical equipment & failure modes
Common applications
- wind-turbine gearbox planet and rotor shafts
- ship propulsion line shafts and reduction gears
- mining SAG/ball-mill drive shafts
- offshore drawworks and winch drums
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
- electrical pitting on VFD-driven motor shafts without grounding protection
- electrical pitting on VFD-driven motor shafts without grounding protection
Selection pitfalls — read before you substitute
- At 120 mm bore, oil-lubricated arrangements toward 3,700 r/min need positive flow and drain design; the 5460 g NF224 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Open NF224 units need application-supplied sealing and a defined lubricant schedule; film thickness is the first failure mode for line contact when viscosity drops at the 120 mm contact.
- Grease limiting speed 3,200 r/min and oil 3,700 r/min are different limits for NF224: 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 215 mm race brinells and releases as vibration within hours.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NF224 skids at 3,200 r/min and fails by smearing long before L10 fatigue.
- The 288/320 kN ratings, 33.5 kN Pu and 5460 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF224 (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 NF224?
NF224 is an NTN NF single-row cylindrical roller bearing to ISO 15: 120 mm bore, 215 mm OD and 40 mm width (4.724 × 8.465 × 1.575 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 288 kN, C0 320 kN, Pu 33.5 kN, grease limiting speed 3,200 r/min, oil 3,700 r/min, mass about 5460 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. NF224 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. NF224 is supplied in the standard open execution shown in the table.
Can NF224 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 NF224?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 143.5 mm, Ew 191.5 mm. The nominal bore/OD remain 120/215 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 3,200 r/min grease / 3,700 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.