NN3030 bearing: complete specifications & equivalents
The NN3030 is a ISO 15 radial bearing sized 150 x 225 x 56 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 | 225 mm |
| Width B | 56 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 370 kN |
| Basic static load rating C0 | 585 kN |
| Fatigue load limit Pu | 59 kN |
| Limiting speed (mechanical) | 2600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 7810 g |
| Manufacturer designation | NTN NN3030 |
| 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 & NN3000-series range
| Bore d | 5.906 in |
|---|---|
| Outer diameter D | 8.858 in |
| Width B | 2.205 in |
| ISO bore code | 30 |
| Radial section height (D−d)/2 | 37.5 mm |
| Smallest bore in NN3000-series | 25 mm |
| Largest outer diameter in NN3000-series | 680 mm |
| Width range across NN3000-series | 16–163 mm |
| Bore position in NN3000-series (smallest first) | 22 of 40 |
| Bore above smallest NN3000-series size | 125 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NN3030 | 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 NN3030 model number is decoded
NTN lists NN3030 on the 150×225 mm envelope, 56 mm wide: a line-contact radial bearing with a machined or stamped steel cage per the precision execution and a grease limiting speed of 2,600 r/min. Numbering ties NN3030 to its envelope: type code NN, series NN3000, 150 mm bore; the 225×56 mm outline therefore swaps dimensionally with other ISO 15 bearings of the same code, though rib arrangements differ by prefix. With C 370 kN and C0 585 kN (C0/C ≈ 1.58) the bearing is proportioned for heavy radial load; the NU design carries no axial load and floats axially on both sides. Speed ratio check: limiting 2,600 r/min is .84 of the 3,100 r/min oil value for NN3030; grease-churn heating closes that gap as fill quantity rises. On NN arrangements confirm which ring is separable before heating: forcing the ribbed ring off over the roller complement damages the cage and rib faces.
Typical equipment & failure modes
Common applications
- coordinate-measuring and semiconductor-equipment drives
- machine-tool main spindles requiring high radial stiffness
- precision gearbox and indexing-drive shafts
- high-rpm motorised grinding and milling spindles
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
- roller-end and raceway scoring from inadequate oil flow under heavy radial load
- fretting corrosion on a loose rotating shaft seat
- false brinelling on standby machines exposed to external vibration
Selection pitfalls — read before you substitute
- At 150 mm bore, oil-lubricated arrangements toward 3,100 r/min need positive flow and drain design; the 7810 g NN3030 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NN3030 skids at 2,600 r/min and fails by smearing long before L10 fatigue.
- Do not replace NN3030 with a deep-groove ball bearing on rating alone: line contact gives 370 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 NN rib arrangement is not interchangeable with another prefix on the same 150 mm seat: double row, ribbed inner ring, separable outer. Swapping NU for NJ changes axial location behaviour even though the 225×56 mm envelope matches.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NN3030 skids at 2,600 r/min and fails by smearing long before L10 fatigue.
- The 370/585 kN ratings, 59 kN Pu and 7810 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NN3030 (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 NN3030?
NN3030 is an NTN NN double-row precision cylindrical roller bearing to ISO 15: 150 mm bore, 225 mm OD and 56 mm width (5.906 × 8.858 × 2.205 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 370 kN, C0 585 kN, Pu 59 kN, grease limiting speed 2,600 r/min, oil 3,100 r/min, mass about 7810 g. It is open, with a machined or stamped steel cage per the precision execution.
What is the difference between NU, NJ, NUP, N and NF cylindrical roller bearings?
NN and NNU are double-row precision designs rather than single-row rib variants: NN has a ribbed inner ring and separable outer ring, NNU the reverse; both give high radial stiffness for spindles and are commonly ordered with P5/P4 precision and a K 1:12 tapered bore for preload setting. NN3030 is the NN execution.
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. NN3030 is supplied in the standard open execution shown in the table.
What does the K tapered bore mean on a precision NN bearing like NN3030?
NN3030 has a cylindrical bore and mounts on a plain machined shaft seat; a K execution (1:12 taper) exists in the NN3000 series when preload must be set by drive-up on a tapered seat.
What speeds and lubrication apply to NN3030?
NTN rates NN3030 at 2,600 r/min with grease and 3,100 r/min with oil. The grease figure is the cage/film mechanical ceiling; the oil figure assumes circulating or carefully supplied oil that removes heat from the line-contact zone.
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.