NJ336 bearing: complete specifications & equivalents
The NJ336 is a ISO 15 radial bearing sized 180 x 380 x 75 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 | 380 mm |
| Width B | 75 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1000 kN |
| Basic static load rating C0 | 1150 kN |
| Fatigue load limit Pu | 103 kN |
| Limiting speed (mechanical) | 1700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 43200 g |
| Manufacturer designation | NTN NJ336 |
| 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 & NJ300-series range
| Bore d | 7.087 in |
|---|---|
| Outer diameter D | 14.961 in |
| Width B | 2.953 in |
| ISO bore code | 36 |
| Radial section height (D−d)/2 | 100 mm |
| Smallest bore in NJ300-series | 17 mm |
| Largest outer diameter in NJ300-series | 580 mm |
| Width range across NJ300-series | 14–108 mm |
| Bore position in NJ300-series (smallest first) | 27 of 33 |
| Bore above smallest NJ300-series size | 163 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ336-ECM | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 180×380×75 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 NJ336 model number is decoded
The NTN order number NJ336 denotes a 180×380×75 mm (7.087 × 14.961 × 2.953 in) cylindrical roller bearing in the NJ300 family, a pressed sheet-steel cage. Numbering ties NJ336 to its envelope: type code NJ, series NJ300, 180 mm bore; the 380×75 mm outline therefore swaps dimensionally with other ISO 15 bearings of the same code, though rib arrangements differ by prefix. With C 1000 kN and C0 1150 kN (C0/C ≈ 1.15) the bearing is proportioned for heavy radial load; the NJ design accepts axial load in one direction and provides one-way shaft location. The 180 mm (7.087 in) bore and 380 mm (14.961 in) OD are ISO 15 boundary values; fillet and shoulder dimensions must still come from the NTN mounting table for the 75 mm-wide ring. 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 NJ336.
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
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- cage distortion after a mounting blow carried through the roller set
- roller-end and raceway scoring from inadequate oil flow under heavy radial load
- fretting corrosion on a loose rotating shaft seat
- fretting corrosion on a loose rotating shaft seat
Selection pitfalls — read before you substitute
- At 180 mm bore, oil-lubricated arrangements toward 2,000 r/min need positive flow and drain design; the 43200 g NJ336 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 380 mm race brinells and releases as vibration within hours.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 380 mm race brinells and releases as vibration within hours.
- Wide (22/23) and light (10/49) executions at 180 mm bore share bore but not OD/width; check the full NJ300 series code before substituting, because housing and shoulder geometry will not interchange.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NJ336 skids at 1,700 r/min and fails by smearing long before L10 fatigue.
- The 1000/1150 kN ratings, 103 kN Pu and 43200 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ336 (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 NJ336?
NJ336 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 180 mm bore, 380 mm OD and 75 mm width (7.087 × 14.961 × 2.953 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1000 kN, C0 1150 kN, Pu 103 kN, grease limiting speed 1,700 r/min, oil 2,000 r/min, mass about 43200 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. NJ336 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. NJ336 is supplied in the standard open execution shown in the table.
Can NJ336 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 NJ336?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 232 mm, Ew 328 mm. The nominal bore/OD remain 180/380 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,700 r/min grease / 2,000 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.