NF218 bearing: complete specifications & equivalents
The NF218 is a ISO 15 radial bearing sized 90 x 160 x 30 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 90 mm |
| Outer diameter D | 160 mm |
| Width B | 30 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 169 kN |
| Basic static load rating C0 | 178 kN |
| Fatigue load limit Pu | 20.3 kN |
| Limiting speed (mechanical) | 4300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2250 g |
| Manufacturer designation | NTN NF218 |
| 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 | 3.543 in |
|---|---|
| Outer diameter D | 6.299 in |
| Width B | 1.181 in |
| ISO bore code | 18 |
| Radial section height (D−d)/2 | 35 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) | 15 of 34 |
| Bore above smallest NF200-series size | 70 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF218 | 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 NF218 model number is decoded
NF218 is an NTN NF cylindrical roller bearing: one integral rib on each ring — separable inner ring with single-direction axial guidance and a defined shaft position, inside the 90×160×30 mm ISO 15 envelope. On the NTN nameplate NF states which ring carries the ribs, which determines whether NF218 floats or locates; the numeric remainder is the ISO 15 series and 90 mm bore reference, not a fit or clearance instruction. NTN prints the raceway diameters for this size — Fw 107 mm and Ew 143 mm — the envelope inside the 90/160 mm bore/OD where the rollers actually run. Rating life at 169 kN C assumes clean oil and adequate film; the 20.3 kN Pu floor means contamination derating — not the C rating alone — governs adjusted life in dusty gearboxes. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 90 mm shaft.
Typical equipment & failure modes
Common applications
- rolling-mill auxiliary drive shafts
- crusher and vibrating-screen drive shafts
- marine gearbox and deck-machinery shafts
- large electric-motor and generator rotors
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
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- fretting corrosion on a loose rotating shaft seat
- brinelling from static overload or impact during handling
Selection pitfalls — read before you substitute
- Induction-heat the 90 mm inner ring (max 120 °C) and mount it before fitting the outer ring; the ring mass makes square guidance essential — driving through the rollers brinells the 160 mm raceway.
- Open NF218 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 90 mm contact.
- The NF rib arrangement is not interchangeable with another prefix on the same 90 mm seat: one rib on each ring. Swapping NU for NJ changes axial location behaviour even though the 160×30 mm envelope matches.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NF218 skids at 4,300 r/min and fails by smearing long before L10 fatigue.
- The NF rib arrangement is not interchangeable with another prefix on the same 90 mm seat: one rib on each ring. Swapping NU for NJ changes axial location behaviour even though the 160×30 mm envelope matches.
- The 169/178 kN ratings, 20.3 kN Pu and 2250 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF218 (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 NF218?
NF218 is an NTN NF single-row cylindrical roller bearing to ISO 15: 90 mm bore, 160 mm OD and 30 mm width (3.543 × 6.299 × 1.181 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 169 kN, C0 178 kN, Pu 20.3 kN, grease limiting speed 4,300 r/min, oil 5,000 r/min, mass about 2250 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. NF218 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. NF218 is listed among the ＊ ULTAGE-marked executions in 2203E.
Can NF218 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 NF218?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 107 mm, Ew 143 mm. The nominal bore/OD remain 90/160 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 4,300 r/min grease / 5,000 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.