NN3034K bearing: complete specifications & equivalents
The NN3034K is a ISO 15 radial bearing sized 170 x 260 x 67 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 170 mm |
| Outer diameter D | 260 mm |
| Width B | 67 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 490 kN |
| Basic static load rating C0 | 775 kN |
| Fatigue load limit Pu | 75 kN |
| Limiting speed (mechanical) | 2300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 12200 g |
| Manufacturer designation | NTN NN3034K |
| 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 | 6.693 in |
|---|---|
| Outer diameter D | 10.236 in |
| Width B | 2.638 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 45 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) | 24 of 40 |
| Bore above smallest NN3000-series size | 145 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NN3034K | 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 NN3034K model number is decoded
NN3034K belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 490 kN dynamic rating in the 170 mm bore. On the NTN nameplate NN states which ring carries the ribs, which determines whether NN3034K floats or locates; the numeric remainder is the ISO 15 series and 170 mm bore reference, not a fit or clearance instruction. Minimum radial load matters: an unloaded NN3034K at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. Equivalent-load planning treats NN3034K as a pure radial bearing: keep P below 490 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. After mounting verify the outer ring slides axially by hand at ambient temperature; a stuck float ring in a NN3034K non-locating position preloads the bearing when the shaft grows.
Typical equipment & failure modes
Common applications
- CNC lathe and machining-centre spindle radial sets
- precision rotary-table and dividing-head bearings
- high-speed turbine and turbo-blower rotor supports
- coordinate-measuring and semiconductor-equipment drives
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- 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
- electrical pitting on VFD-driven motor shafts without grounding protection
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- At 170 mm bore, oil-lubricated arrangements toward 2,700 r/min need positive flow and drain design; the 12200 g NN3034K ring stores enough heat that grease-only duty needs a careful relubrication calculation.
- The 67 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 170 mm inner ring.
- The 45.0 mm section at 170 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 67 mm-wide cavity.
- Do not replace NN3034K with a deep-groove ball bearing on rating alone: line contact gives 490 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- Do not replace NN3034K with a deep-groove ball bearing on rating alone: line contact gives 490 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 490/775 kN ratings, 75 kN Pu and 12200 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NN3034K (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 NN3034K?
NN3034K is an NTN NN double-row precision cylindrical roller bearing to ISO 15: 170 mm bore, 260 mm OD and 67 mm width (6.693 × 10.236 × 2.638 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 490 kN, C0 775 kN, Pu 75 kN, grease limiting speed 2,300 r/min, oil 2,700 r/min, mass about 12200 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. NN3034K 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. NN3034K is supplied in the standard open execution shown in the table.
What does the K tapered bore mean on a precision NN bearing like NN3034K?
The K suffix denotes a 1:12 tapered bore. NN3034K mounts on a tapered shaft seat or adapter sleeve and is driven up to a measured residual clearance or preload — this is how precision spindle bearings achieve stiffness without locknut guesswork; the cylindrical-bore NN3034 execution of the same envelope mounts on a plain seat.
What speeds and lubrication apply to NN3034K?
NTN rates NN3034K at 2,300 r/min with grease and 2,700 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.