NJ236 bearing: complete specifications & equivalents
The NJ236 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 NJ236 |
| 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 | 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 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) | 28 of 36 |
| Bore above smallest NJ200-series size | 165 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ236-ECML | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 180×320×52 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 NJ236 model number is decoded
NJ236 is the standard section of the NTN NJ200 dimension series for a 180 mm shaft — 550 kN of basic dynamic capacity in a 17300 g, open bearing. Reading the code: NJ for the one-direction-locating 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 prints two speed ceilings: 2,000 r/min grease and 2,400 r/min oil — the pressed-steel cage and lubricant film set the real limit at the 180 mm bore. The 3.1 kN-per-mm-bore figure (550 kN over 180 mm) lets a NJ236 interchange candidate be screened quickly against the same-envelope ball or roller alternatives. Mount the separable inner ring + roller assembly on the shaft first and slide the outer ring into the housing; never press the outer ring through the rollers of NJ236.
Typical equipment & failure modes
Common applications
- ship propulsion line shafts and reduction gears
- mining SAG/ball-mill drive shafts
- offshore drawworks and winch drums
- heavy press and large gearbox main shafts
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
- brinelling from static overload or impact during handling
- 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 NJ236 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Open NJ236 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.
- The 70.0 mm section at 180 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 52 mm-wide cavity.
- The 52 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 180 mm inner ring.
- If the shaft must be located both ways, do not use NJ236 alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- The 550/675 kN ratings, 62.5 kN Pu and 17300 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ236 (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 NJ236?
NJ236 is an NTN NJ 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. NJ236 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. NJ236 is supplied in the standard open execution shown in the table.
Can NJ236 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 NJ236?
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.