NF406 bearing: complete specifications & equivalents
The NF406 is a ISO 15 radial bearing sized 30 x 90 x 23 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 30 mm |
| Outer diameter D | 90 mm |
| Width B | 23 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 69.5 kN |
| Basic static load rating C0 | 55 kN |
| Fatigue load limit Pu | 6.7 kN |
| Limiting speed (mechanical) | 7300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 732 g |
| Manufacturer designation | NTN NF406 |
| 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 & NF400-series range
| Bore d | 1.181 in |
|---|---|
| Outer diameter D | 3.543 in |
| Width B | 0.906 in |
| ISO bore code | 06 |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in NF400-series | 25 mm |
| Largest outer diameter in NF400-series | 200 mm |
| Width range across NF400-series | 21–48 mm |
| Bore position in NF400-series (smallest first) | 2 of 12 |
| Bore above smallest NF400-series size | 5 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF406 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; standard interchange — confirm clearance class and precision with the supplier. |
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 NF406 model number is decoded
NF406 belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E: line-contact rollers between ground raceways for a 69.5 kN dynamic rating in the 30 mm bore. Reading the code: NF for the rib-on-each-ring type, then the ISO 15 diameter/width series and the bore code — ×5 = 30 mm (00–03 use the 10/12/15/17 exception table). NTN prints two speed ceilings: 7,300 r/min grease and 8,500 r/min oil — the pressed-steel cage and lubricant film set the real limit at the 30 mm bore. The 30 mm (1.181 in) bore and 90 mm (3.543 in) OD are ISO 15 boundary values; fillet and shoulder dimensions must still come from the NTN mounting table for the 23 mm-wide ring. Housing and shaft fillets must clear the ring chamfers of NF406; an oversized radius locks the ring on its face and tilts the 23 mm-wide seat.
Typical equipment & failure modes
Common applications
- industrial gearbox input and output shafts
- medium electric-motor and generator shafts
- pump and compressor crankshafts and rotors
- machine-tool gearbox and spindle radial sets
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
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- brinelling from static overload or impact during handling
- brinelling from static overload or impact during handling
Selection pitfalls — read before you substitute
- On this 30 mm bore, shaft thermal growth can preload the inner ring if the fit is too tight; verify residual interference at temperature and confirm the float ring still slides after mounting NF406.
- Wide (22/23) and light (10/49) executions at 30 mm bore share bore but not OD/width; check the full NF400 series code before substituting, because housing and shoulder geometry will not interchange.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NF406 skids at 7,300 r/min and fails by smearing long before L10 fatigue.
- The 30.0 mm section at 30 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 23 mm-wide cavity.
- If the shaft must be located both ways, do not use NF406 alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- The 69.5/55 kN ratings, 6.7 kN Pu and 732 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF406 (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 NF406?
NF406 is an NTN NF single-row cylindrical roller bearing to ISO 15: 30 mm bore, 90 mm OD and 23 mm width (1.181 × 3.543 × 0.906 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 69.5 kN, C0 55 kN, Pu 6.7 kN, grease limiting speed 7,300 r/min, oil 8,500 r/min, mass about 732 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. NF406 is one integral rib on each ring — separable inner ring with single-direction axial guidance and a defined shaft position.
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. NF406 is supplied in the standard open execution shown in the table.
Can NF406 take axial load and locate a shaft?
the NF design gives one-direction axial guidance via its single outer-ring rib. The loose rib ring still only suits light/short-duration axial guidance; heavy thrust belongs to a dedicated thrust bearing.
What do Fw and Ew mean for NF406?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 45 mm, Ew 73 mm. The nominal bore/OD remain 30/90 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 7,300 r/min grease / 8,500 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.