NJ1038 bearing: complete specifications & equivalents
The NJ1038 is a ISO 15 radial bearing sized 190 x 290 x 46 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 190 mm |
| Outer diameter D | 290 mm |
| Width B | 46 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 390 kN |
| Basic static load rating C0 | 510 kN |
| Fatigue load limit Pu | 48 kN |
| Limiting speed (mechanical) | 2300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 10500 g |
| Manufacturer designation | NTN NJ1038 |
| 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 & NJ1000-series range
| Bore d | 7.48 in |
|---|---|
| Outer diameter D | 11.417 in |
| Width B | 1.811 in |
| ISO bore code | 38 |
| Radial section height (D−d)/2 | 50 mm |
| Smallest bore in NJ1000-series | 25 mm |
| Largest outer diameter in NJ1000-series | 720 mm |
| Width range across NJ1000-series | 12–100 mm |
| Bore position in NJ1000-series (smallest first) | 26 of 42 |
| Bore above smallest NJ1000-series size | 165 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ1038-ML | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 190×290×46 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 NJ1038 model number is decoded
NJ1038 is an NTN NJ cylindrical roller bearing: two integral ribs on the inner ring and one rib on the outer ring — it locates the shaft in one axial direction, inside the 190×290×46 mm ISO 15 envelope. The leading NJ defines the rib arrangement (inner ring two ribs + one outer rib); the dimension-series digits and the two-digit bore code resolve to 190 mm, with 290 mm OD and 46 mm width from the ISO 15 general plan. NTN prints the raceway diameters for this size — Fw 215 mm and Ew 265 mm — the envelope inside the 190/290 mm bore/OD where the rollers actually run. With the inner ring rotating, catalogue practice is a m6/n6 shaft seat and an H7/H6 housing; the outer ring must remain free to creep slightly axially in non-locating NJ arrangements. On NJ arrangements confirm which ring is separable before heating: forcing the ribbed ring off over the roller complement damages the cage and rib faces.
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 distortion after a mounting blow carried through the roller set
- micro-pitting when the EHL film falls below the composite roughness at high specific load
- brinelling from static overload or impact during handling
- rolling-contact fatigue after the catalogue L10 life is exceeded
Selection pitfalls — read before you substitute
- At 190 mm bore, oil-lubricated arrangements toward 2,700 r/min need positive flow and drain design; the 10500 g NJ1038 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NJ1038 skids at 2,300 r/min and fails by smearing long before L10 fatigue.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NJ1038 skids at 2,300 r/min and fails by smearing long before L10 fatigue.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 290 mm race brinells and releases as vibration within hours.
- The NJ rib arrangement is not interchangeable with another prefix on the same 190 mm seat: inner ring two ribs + one outer rib. Swapping NU for NJ changes axial location behaviour even though the 290×46 mm envelope matches.
- The 390/510 kN ratings, 48 kN Pu and 10500 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ1038 (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 NJ1038?
NJ1038 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 190 mm bore, 290 mm OD and 46 mm width (7.48 × 11.417 × 1.811 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 390 kN, C0 510 kN, Pu 48 kN, grease limiting speed 2,300 r/min, oil 2,700 r/min, mass about 10500 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. NJ1038 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. NJ1038 is supplied in the standard open execution shown in the table.
Can NJ1038 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 NJ1038?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 215 mm, Ew 265 mm. The nominal bore/OD remain 190/290 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 2,300 r/min grease / 2,700 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.