NJ330 bearing: complete specifications & equivalents
The NJ330 is a ISO 15 radial bearing sized 150 x 320 x 65 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 150 mm |
| Outer diameter D | 320 mm |
| Width B | 65 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 735 kN |
| Basic static load rating C0 | 805 kN |
| Fatigue load limit Pu | 76 kN |
| Limiting speed (mechanical) | 2100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 24700 g |
| Manufacturer designation | NTN NJ330 |
| 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 | 5.906 in |
|---|---|
| Outer diameter D | 12.598 in |
| Width B | 2.559 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 85 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) | 24 of 33 |
| Bore above smallest NJ300-series size | 133 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ330-ECML | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 150×320×65 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 NJ330 model number is decoded
NJ330 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 735 kN dynamic rating in the 150 mm bore. On the NTN nameplate NJ states which ring carries the ribs, which determines whether NJ330 floats or locates; the numeric remainder is the ISO 15 series and 150 mm bore reference, not a fit or clearance instruction. The 85.0 mm radial section ((320−150)/2) frames the roller complement; capacity per millimetre of bore is about 4.9 kN/mm before application factors. Selection arithmetic: Pu 76 kN is the fatigue load limit feeding the adjusted-life equation, and the C0/C ratio of 1.10 (805/735 kN) shows the high-static-capacity proportioning of this 150 mm bore. After mounting verify the outer ring slides axially by hand at ambient temperature; a stuck float ring in a NJ330 non-locating position preloads the bearing when the shaft grows.
Typical equipment & failure modes
Common applications
- mining SAG/ball-mill drive shafts
- offshore drawworks and winch drums
- heavy press and large gearbox main shafts
- rolling-mill work-roll and backup-roll positions
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
- roller-end and raceway scoring from inadequate oil flow under heavy radial load
- electrical pitting on VFD-driven motor shafts without grounding protection
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
Selection pitfalls — read before you substitute
- At 150 mm bore, oil-lubricated arrangements toward 2,500 r/min need positive flow and drain design; the 24700 g NJ330 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 735/805 kN pair here belongs to NJ330 as printed, not to the bare size.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NJ330 skids at 2,100 r/min and fails by smearing long before L10 fatigue.
- Do not replace NJ330 with a deep-groove ball bearing on rating alone: line contact gives 735 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- The 85.0 mm section at 150 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 65 mm-wide cavity.
- The 735/805 kN ratings, 76 kN Pu and 24700 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NJ330 (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 NJ330?
NJ330 is an NTN NJ single-row cylindrical roller bearing to ISO 15: 150 mm bore, 320 mm OD and 65 mm width (5.906 × 12.598 × 2.559 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 735 kN, C0 805 kN, Pu 76 kN, grease limiting speed 2,100 r/min, oil 2,500 r/min, mass about 24700 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. NJ330 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. NJ330 is supplied in the standard open execution shown in the table.
Can NJ330 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 NJ330?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 193 mm, Ew 277 mm. The nominal bore/OD remain 150/320 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 2,100 r/min grease / 2,500 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.