NF408 bearing: complete specifications & equivalents
The NF408 is a ISO 15 radial bearing sized 40 x 110 x 27 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 40 mm |
| Outer diameter D | 110 mm |
| Width B | 27 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 106 kN |
| Basic static load rating C0 | 89 kN |
| Fatigue load limit Pu | 10.9 kN |
| Limiting speed (mechanical) | 5700 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1270 g |
| Manufacturer designation | NTN NF408 |
| 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 | 1.575 in |
|---|---|
| Outer diameter D | 4.331 in |
| Width B | 1.063 in |
| ISO bore code | 08 |
| Radial section height (D−d)/2 | 35 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) | 4 of 12 |
| Bore above smallest NF400-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF408 | 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 NF408 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, NF408 appears as a 40 mm bore single-row cylindrical roller bearing (106 kN C / 89 kN C0) with a pressed sheet-steel cage, listed to the ISO 15 boundary plan. Digit by digit, NF408 reads as NF (one rib on each ring), ISO 15 series, and bore 40 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. Minimum radial load matters: an unloaded NF408 at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. The 2.6 kN-per-mm-bore figure (106 kN over 40 mm) lets a NF408 interchange candidate be screened quickly against the same-envelope ball or roller alternatives. Keep the open bearing wrapped until fitting: the line-contact raceways of the 40 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.
Typical equipment & failure modes
Common applications
- material-handling drum and wheel shafts
- papermaking and printing auxiliary drives
- fan and blower rotor positions
- industrial gearbox input and output shafts
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- pressed-steel cage pocket wear when rollers skid at light load or too-thin lubricant
- micro-pitting when the EHL film falls below the composite roughness at high specific load
- rolling-contact fatigue after the catalogue L10 life is exceeded
- electrical pitting on VFD-driven motor shafts without grounding protection
Selection pitfalls — read before you substitute
- On this 40 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 NF408.
- The NF rib arrangement is not interchangeable with another prefix on the same 40 mm seat: one rib on each ring. Swapping NU for NJ changes axial location behaviour even though the 110×27 mm envelope matches.
- The 35.0 mm section at 40 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 27 mm-wide cavity.
- Do not replace NF408 with a deep-groove ball bearing on rating alone: line contact gives 106 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 NF408 with a deep-groove ball bearing on rating alone: line contact gives 106 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 106/89 kN ratings, 10.9 kN Pu and 1270 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF408 (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 NF408?
NF408 is an NTN NF single-row cylindrical roller bearing to ISO 15: 40 mm bore, 110 mm OD and 27 mm width (1.575 × 4.331 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 106 kN, C0 89 kN, Pu 10.9 kN, grease limiting speed 5,700 r/min, oil 6,700 r/min, mass about 1270 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. NF408 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. NF408 is supplied in the standard open execution shown in the table.
Can NF408 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 NF408?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 58 mm, Ew 92 mm. The nominal bore/OD remain 40/110 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 5,700 r/min grease / 6,700 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.