NJ328 bearing: complete specifications & equivalents
The NJ328 is a ISO 15 radial bearing sized 140 x 300 x 62 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 140 mm |
| Outer diameter D | 300 mm |
| Width B | 62 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 685 kN |
| Basic static load rating C0 | 745 kN |
| Fatigue load limit Pu | 72 kN |
| Limiting speed (mechanical) | 2300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 20700 g |
| Manufacturer designation | NTN NJ328 |
| 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 | 5.512 in |
|---|---|
| Outer diameter D | 11.811 in |
| Width B | 2.441 in |
| ISO bore code | 28 |
| Radial section height (D−d)/2 | 80 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) | 23 of 33 |
| Bore above smallest NJ300-series size | 123 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ328-ECJ | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 140×300×62 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 NJ328 model number is decoded
For pure radial duty on a 140 mm shaft NTN supplies NJ328: two integral ribs on the inner ring and one rib on the outer ring; the open execution is rated 2,300 r/min on grease and 2,700 r/min on oil. Numbering ties NJ328 to its envelope: type code NJ, series NJ300, 140 mm bore; the 300×62 mm outline therefore swaps dimensionally with other ISO 15 bearings of the same code, though rib arrangements differ by prefix. With C 685 kN and C0 745 kN (C0/C ≈ 1.09) the bearing is proportioned for heavy radial load; the NJ design accepts axial load in one direction and provides one-way shaft location. Mass 20700 g for the 140×300×62 mm NJ328 execution covers the pressed-steel cage and full roller complement; substitute on mass plus rating, not envelope alone. Heat the inner ring to max 120 °C for the 140 mm interference fit and support the ring face square during fitting; cocking over a keyway brinells the raceway before first rotation.
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
- 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 140 mm bore, oil-lubricated arrangements toward 2,700 r/min need positive flow and drain design; the 20700 g NJ328 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The 80.0 mm section at 140 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 62 mm-wide cavity.
- Wide (22/23) and light (10/49) executions at 140 mm bore share bore but not OD/width; check the full NJ300 series code before substituting, because housing and shoulder geometry will not interchange.
- The 80.0 mm section at 140 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 62 mm-wide cavity.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NJ328 skids at 2,300 r/min and fails by smearing long before L10 fatigue.
- The 685/745 kN ratings, 72 kN Pu and 20700 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ328 (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 NJ328?
NJ328 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 140 mm bore, 300 mm OD and 62 mm width (5.512 × 11.811 × 2.441 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 685 kN, C0 745 kN, Pu 72 kN, grease limiting speed 2,300 r/min, oil 2,700 r/min, mass about 20700 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. NJ328 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. NJ328 is supplied in the standard open execution shown in the table.
Can NJ328 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 NJ328?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 180 mm, Ew 260 mm. The nominal bore/OD remain 140/300 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.