NJ218 bearing: complete specifications & equivalents
The NJ218 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 NJ218 |
| 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 & NJ200-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 NJ200-series | 15 mm |
| Largest outer diameter in NJ200-series | 580 mm |
| Width range across NJ200-series | 11–92 mm |
| Bore position in NJ200-series (smallest first) | 17 of 36 |
| Bore above smallest NJ200-series size | 75 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ218-ECP | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 90×160×30 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 NJ218 model number is decoded
NJ218 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 169 kN dynamic rating in the 90 mm bore. On the NTN nameplate NJ states which ring carries the ribs, which determines whether NJ218 floats or locates; the numeric remainder is the ISO 15 series and 90 mm bore reference, not a fit or clearance instruction. the bare number is the standard-capacity open execution with the normal pressed-steel cage; the ＊ symbol printed before the number in 2203E marks the ULTAGE new-generation specification — upgraded material/geometry and longer rating life, not part of the order code; quote the full NJ218 designation when purchasing. Equivalent-load planning treats NJ218 as a pure radial bearing: keep P below 169 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 90 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.
Typical equipment & failure modes
Common applications
- large electric-motor and generator rotors
- cement and mining conveyor drive pulleys
- heavy industrial gearbox and reducer shafts
- large pump, turbine and compressor rotors
Known failure patterns
- inner-ring raceway spalling from overload in the line-contact Hertzian zone
- pressed-steel cage pocket wear when rollers skid at light load or too-thin lubricant
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- false brinelling on standby machines exposed to external vibration
- 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.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 160 mm race brinells and releases as vibration within hours.
- Grease limiting speed 4,300 r/min and oil 5,000 r/min are different limits for NJ218: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- The 35.0 mm section at 90 mm bore leaves a narrow oil path; with the standard cage the relubrication groove and oil-level design must keep grease from churning in the 30 mm-wide cavity.
- The 30 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 90 mm inner ring.
- The 169/178 kN ratings, 20.3 kN Pu and 2250 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ218 (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 NJ218?
NJ218 is an NTN NJ 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. NJ218 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. NJ218 is listed among the ＊ ULTAGE-marked executions in 2203E.
Can NJ218 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 NJ218?
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.