NJ1068 bearing: complete specifications & equivalents
The NJ1068 is a ISO 15 radial bearing sized 340 x 520 x 82 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 340 mm |
| Outer diameter D | 520 mm |
| Width B | 82 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 1160 kN |
| Basic static load rating C0 | 1670 kN |
| Fatigue load limit Pu | 132 kN |
| Limiting speed (mechanical) | 1200 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 60800 g |
| Manufacturer designation | NTN NJ1068 |
| 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 | 13.386 in |
|---|---|
| Outer diameter D | 20.472 in |
| Width B | 3.228 in |
| ISO bore code | 68 |
| Radial section height (D−d)/2 | 90 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) | 34 of 42 |
| Bore above smallest NJ1000-series size | 315 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ1068 | 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 NJ1068 model number is decoded
NTN lists NJ1068 on the 340×520 mm envelope, 82 mm wide: a line-contact radial bearing with a pressed sheet-steel cage and a grease limiting speed of 1,200 r/min. Digit by digit, NJ1068 reads as NJ (inner ring two ribs + one outer rib), ISO 15 series, and bore 340 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. NTN prints two speed ceilings: 1,200 r/min grease and 1,400 r/min oil — the pressed-steel cage and lubricant film set the real limit at the 340 mm bore. The 340 mm (13.386 in) bore and 520 mm (20.472 in) OD are ISO 15 boundary values; fillet and shoulder dimensions must still come from the NTN mounting table for the 82 mm-wide ring. Housing and shaft fillets must clear the ring chamfers of NJ1068; an oversized radius locks the ring on its face and tilts the 82 mm-wide seat.
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
- 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
- hard-particle indentation of raceways in unfiltered oil or open arrangements
- fretting corrosion on a loose rotating shaft seat
Selection pitfalls — read before you substitute
- At 340 mm bore, oil-lubricated arrangements toward 1,400 r/min need positive flow and drain design; the 60800 g NJ1068 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The 90.0 mm section at 340 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 82 mm-wide cavity.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 1160/1670 kN pair here belongs to NJ1068 as printed, not to the bare size.
- The NJ rib arrangement is not interchangeable with another prefix on the same 340 mm seat: inner ring two ribs + one outer rib. Swapping NU for NJ changes axial location behaviour even though the 520×82 mm envelope matches.
- If the shaft must be located both ways, do not use NJ1068 alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- The 1160/1670 kN ratings, 132 kN Pu and 60800 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ1068 (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 NJ1068?
NJ1068 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 340 mm bore, 520 mm OD and 82 mm width (13.386 × 20.472 × 3.228 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 1160 kN, C0 1670 kN, Pu 132 kN, grease limiting speed 1,200 r/min, oil 1,400 r/min, mass about 60800 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. NJ1068 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. NJ1068 is supplied in the standard open execution shown in the table.
Can NJ1068 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 NJ1068?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 385 mm, Ew 475 mm. The nominal bore/OD remain 340/520 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 1,200 r/min grease / 1,400 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.