NJ1008 bearing: complete specifications & equivalents
The NJ1008 is a ISO 15 radial bearing sized 40 x 68 x 15 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 40 mm |
| Outer diameter D | 68 mm |
| Width B | 15 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 30.5 kN |
| Basic static load rating C0 | 29 kN |
| Fatigue load limit Pu | 3.55 kN |
| Limiting speed (mechanical) | 11000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 217 g |
| Manufacturer designation | NTN NJ1008 |
| 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 | 1.575 in |
|---|---|
| Outer diameter D | 2.677 in |
| Width B | 0.591 in |
| ISO bore code | 08 |
| Radial section height (D−d)/2 | 14 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) | 4 of 42 |
| Bore above smallest NJ1000-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ1008 | 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 NJ1008 model number is decoded
The NTN order number NJ1008 denotes a 40×68×15 mm (1.575 × 2.677 × 0.591 in) cylindrical roller bearing in the NJ1000 family, a pressed sheet-steel cage. Reading the code: NJ for the one-direction-locating type, then the ISO 15 diameter/width series and the bore code — ×5 = 40 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. Selection arithmetic: Pu 3.55 kN is the fatigue load limit feeding the adjusted-life equation, and the C0/C ratio of 0.95 (29/30.5 kN) shows the high-static-capacity proportioning of this 40 mm bore. After mounting verify the outer ring slides axially by hand at ambient temperature; a stuck float ring in a NJ1008 non-locating position preloads the bearing when the shaft grows.
Typical equipment & failure modes
Common applications
- material-handling drum and wheel shafts
- papermaking and printing auxiliary drives
- fan and blower rotor positions
- industrial gearbox input and output shafts
Known failure patterns
- inner-ring raceway spalling from overload in the line-contact Hertzian zone
- 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
- false brinelling on standby machines exposed to external vibration
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- On this 40 mm bore, shaft thermal growth can preload the inner ring if the fit is too tight; verify residual interference at temperature and confirm the float ring still slides after mounting NJ1008.
- The 15 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 40 mm inner ring.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 68 mm race brinells and releases as vibration within hours.
- The 15 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 40 mm inner ring.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 30.5/29 kN pair here belongs to NJ1008 as printed, not to the bare size.
- The 30.5/29 kN ratings, 3.55 kN Pu and 217 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ1008 (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 NJ1008?
NJ1008 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 40 mm bore, 68 mm OD and 15 mm width (1.575 × 2.677 × 0.591 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 30.5 kN, C0 29 kN, Pu 3.55 kN, grease limiting speed 11,000 r/min, oil 13,000 r/min, mass about 217 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. NJ1008 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. NJ1008 is supplied in the standard open execution shown in the table.
Can NJ1008 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 NJ1008?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 47 mm, Ew 61 mm. The nominal bore/OD remain 40/68 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 11,000 r/min grease / 13,000 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.