NF236 bearing: complete specifications & equivalents
The NF236 is a ISO 15 radial bearing sized 180 x 320 x 52 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 180 mm |
| Outer diameter D | 320 mm |
| Width B | 52 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 550 kN |
| Basic static load rating C0 | 675 kN |
| Fatigue load limit Pu | 62.5 kN |
| Limiting speed (mechanical) | 2000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 17300 g |
| Manufacturer designation | NTN NF236 |
| 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 | 7.087 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 2.047 in |
| ISO bore code | 36 |
| Radial section height (D−d)/2 | 70 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) | 26 of 34 |
| Bore above smallest NF200-series size | 160 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF236 | 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 NF236 model number is decoded
For pure radial duty on a 180 mm shaft NTN supplies NF236: one integral rib on each ring; the open execution is rated 2,000 r/min on grease and 2,400 r/min on oil. Reading the code: NF for the rib-on-each-ring type, then the ISO 15 diameter/width series and the bore code — ×5 = 180 mm (00–03 use the 10/12/15/17 exception table). NTN ships these bearings open with normal (CN) radial clearance and P0 tolerance as standard; precision classes and C3/C4 clearance are separate order suffixes, not part of NF236. Speed ratio check: limiting 2,000 r/min is .83 of the 2,400 r/min oil value for NF236; grease-churn heating closes that gap as fill quantity rises. Housing and shaft fillets must clear the ring chamfers of NF236; an oversized radius locks the ring on its face and tilts the 52 mm-wide seat.
Typical equipment & failure modes
Common applications
- rolling-mill work-roll and backup-roll positions
- large turbine and generator rotor bearings
- wind-turbine gearbox planet and rotor shafts
- ship propulsion line shafts and reduction gears
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
- electrical pitting on VFD-driven motor shafts without grounding protection
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- At 180 mm bore, oil-lubricated arrangements toward 2,400 r/min need positive flow and drain design; the 17300 g NF236 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Grease limiting speed 2,000 r/min and oil 2,400 r/min are different limits for NF236: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- Grease limiting speed 2,000 r/min and oil 2,400 r/min are different limits for NF236: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
- Open NF236 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 180 mm contact.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 320 mm race brinells and releases as vibration within hours.
- The 550/675 kN ratings, 62.5 kN Pu and 17300 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF236 (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 NF236?
NF236 is an NTN NF single-row cylindrical roller bearing to ISO 15: 180 mm bore, 320 mm OD and 52 mm width (7.087 × 12.598 × 2.047 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 550 kN, C0 675 kN, Pu 62.5 kN, grease limiting speed 2,000 r/min, oil 2,400 r/min, mass about 17300 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. NF236 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. NF236 is supplied in the standard open execution shown in the table.
Can NF236 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 NF236?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 218 mm, Ew 282 mm. The nominal bore/OD remain 180/320 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 2,000 r/min grease / 2,400 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.