NJ1024 bearing: complete specifications & equivalents
The NJ1024 is a ISO 15 radial bearing sized 120 x 180 x 28 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 120 mm |
| Outer diameter D | 180 mm |
| Width B | 28 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 154 kN |
| Basic static load rating C0 | 191 kN |
| Fatigue load limit Pu | 20.6 kN |
| Limiting speed (mechanical) | 3800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2400 g |
| Manufacturer designation | NTN NJ1024 |
| 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 | 4.724 in |
|---|---|
| Outer diameter D | 7.087 in |
| Width B | 1.102 in |
| ISO bore code | 24 |
| Radial section height (D−d)/2 | 30 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) | 19 of 42 |
| Bore above smallest NJ1000-series size | 95 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ1024 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
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 NJ1024 model number is decoded
NJ1024 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 120×180×28 mm ISO 15 envelope. Reading the code: NJ for the one-direction-locating type, then the ISO 15 diameter/width series and the bore code — ×5 = 120 mm (00–03 use the 10/12/15/17 exception table). The separable ring comes off without removing the roller assembly from the other ring, which eases inspection and lets the non-locating arrangement accommodate thermal shaft growth. Mass 2400 g for the 120×180×28 mm NJ1024 execution covers the pressed-steel cage and full roller complement; substitute on mass plus rating, not envelope alone. Housing and shaft fillets must clear the ring chamfers of NJ1024; an oversized radius locks the ring on its face and tilts the 28 mm-wide seat.
Typical equipment & failure modes
Common applications
- offshore drawworks and winch drums
- heavy press and large gearbox main shafts
- rolling-mill work-roll and backup-roll positions
- large turbine and generator rotor bearings
Known failure patterns
- inner-ring raceway spalling from overload in the line-contact Hertzian zone
- 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
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
- fretting corrosion on a loose rotating shaft seat
Selection pitfalls — read before you substitute
- At 120 mm bore, oil-lubricated arrangements toward 4,400 r/min need positive flow and drain design; the 2400 g NJ1024 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 180 mm race brinells and releases as vibration within hours.
- The 28 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 120 mm inner ring.
- The NJ rib arrangement is not interchangeable with another prefix on the same 120 mm seat: inner ring two ribs + one outer rib. Swapping NU for NJ changes axial location behaviour even though the 180×28 mm envelope matches.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 154/191 kN pair here belongs to NJ1024 as printed, not to the bare size.
- The 154/191 kN ratings, 20.6 kN Pu and 2400 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ1024 (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 NJ1024?
NJ1024 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 120 mm bore, 180 mm OD and 28 mm width (4.724 × 7.087 × 1.102 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 154 kN, C0 191 kN, Pu 20.6 kN, grease limiting speed 3,800 r/min, oil 4,400 r/min, mass about 2400 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. NJ1024 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. NJ1024 is supplied in the standard open execution shown in the table.
Can NJ1024 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 NJ1024?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 135 mm, Ew 165 mm. The nominal bore/OD remain 120/180 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 3,800 r/min grease / 4,400 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.