NN3005K bearing: complete specifications & equivalents
The NN3005K is a ISO 15 radial bearing sized 25 x 47 x 16 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 25 mm |
| Outer diameter D | 47 mm |
| Width B | 16 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 28.6 kN |
| Basic static load rating C0 | 30 kN |
| Fatigue load limit Pu | 3.65 kN |
| Limiting speed (mechanical) | 14000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 121 g |
| Manufacturer designation | NTN NN3005K |
| 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 | 0.984 in |
|---|---|
| Outer diameter D | 1.85 in |
| Width B | 0.63 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 11 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) | 1 of 40 |
| Bore above smallest NN3000-series size | 0 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NN3005K | 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 NN3005K model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, NN3005K appears as a 25 mm bore single-row cylindrical roller bearing (28.6 kN C / 30 kN C0) with a machined or stamped steel cage per the precision execution, listed to the ISO 15 boundary plan. Reading the code: NN for the double-row precision type, then the ISO 15 diameter/width series and the bore code — ×5 = 25 mm (00–03 use the 10/12/15/17 exception table). The separable ring comes off without removing the roller assembly from the other ring, which eases inspection and lets the non-locating arrangement accommodate thermal shaft growth. Rating life at 28.6 kN C assumes clean oil and adequate film; the 3.65 kN Pu floor means contamination derating — not the C rating alone — governs adjusted life in dusty gearboxes. After mounting verify the outer ring slides axially by hand at ambient temperature; a stuck float ring in a NN3005K 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
- 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
- brinelling from static overload or impact during handling
- rolling-contact fatigue after the catalogue L10 life is exceeded
Selection pitfalls — read before you substitute
- Small 25 mm-bore cylindrical rollers are skid-sensitive: ensure the radial load exceeds the minimum-load floor at operating speed, or the NN3005K rollers smear even with correct grease.
- The NN rib arrangement is not interchangeable with another prefix on the same 25 mm seat: double row, ribbed inner ring, separable outer. Swapping NU for NJ changes axial location behaviour even though the 47×16 mm envelope matches.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 47 mm race brinells and releases as vibration within hours.
- The 16 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 25 mm inner ring.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 28.6/30 kN pair here belongs to NN3005K as printed, not to the bare size.
- The 28.6/30 kN ratings, 3.65 kN Pu and 121 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NN3005K (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 NN3005K?
NN3005K is an NTN NN double-row precision cylindrical roller bearing to ISO 15: 25 mm bore, 47 mm OD and 16 mm width (0.984 × 1.85 × 0.63 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 28.6 kN, C0 30 kN, Pu 3.65 kN, grease limiting speed 14,000 r/min, oil 17,000 r/min, mass about 121 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. NN3005K 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. NN3005K is supplied in the standard open execution shown in the table.
What does the K tapered bore mean on a precision NN bearing like NN3005K?
The K suffix denotes a 1:12 tapered bore. NN3005K 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 NN3005 execution of the same envelope mounts on a plain seat.
What do Fw and Ew mean for NN3005K?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Ew 41.329 mm. The nominal bore/OD remain 25/47 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 14,000 r/min grease / 17,000 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.