NF307EA bearing: complete specifications & equivalents
The NF307EA is a ISO 15 radial bearing sized 35 x 80 x 21 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 35 mm |
| Outer diameter D | 80 mm |
| Width B | 21 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 83.5 kN |
| Basic static load rating C0 | 71 kN |
| Fatigue load limit Pu | 8.65 kN |
| Limiting speed (mechanical) | 8100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 483 g |
| Manufacturer designation | NTN NF307EA |
| 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 & NF300-series range
| Bore d | 1.378 in |
|---|---|
| Outer diameter D | 3.15 in |
| Width B | 0.827 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 22.5 mm |
| Smallest bore in NF300-series | 20 mm |
| Largest outer diameter in NF300-series | 580 mm |
| Width range across NF300-series | 15–108 mm |
| Bore position in NF300-series (smallest first) | 4 of 32 |
| Bore above smallest NF300-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NF307EA | 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 NF307EA model number is decoded
The NTN order number NF307EA denotes a 35×80×21 mm (1.378 × 3.15 × 0.827 in) cylindrical roller bearing in the NF300 family, the EA high-capacity pressed sheet-steel cage. The leading NF defines the rib arrangement (one rib on each ring); the dimension-series digits and the two-digit bore code resolve to 35 mm, with 80 mm OD and 21 mm width from the ISO 15 general plan. NTN ships these bearings open with normal (CN) radial clearance and P0 tolerance as standard; precision classes and C3/C4 clearance are separate order suffixes, not part of NF307EA. Equivalent-load planning treats NF307EA as a pure radial bearing: keep P below 83.5 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. Mount the separable inner ring + roller assembly on the shaft first and slide the outer ring into the housing; never press the outer ring through the rollers of NF307EA.
Typical equipment & failure modes
Common applications
- papermaking and printing auxiliary drives
- fan and blower rotor positions
- industrial gearbox input and output shafts
- medium electric-motor and generator shafts
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
- fretting corrosion on a loose rotating shaft seat
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- On this 35 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 NF307EA.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NF307EA skids at 8,100 r/min and fails by smearing long before L10 fatigue.
- Minimum radial load is frequently missed in oversized motor and fan selections: an underloaded NF307EA skids at 8,100 r/min and fails by smearing long before L10 fatigue.
- If the shaft must be located both ways, do not use NF307EA alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 80 mm race brinells and releases as vibration within hours.
- The 83.5/71 kN ratings, 8.65 kN Pu and 483 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NF307EA (EA pressed-steel-cage 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 NF307EA?
NF307EA is an NTN NF single-row cylindrical roller bearing to ISO 15: 35 mm bore, 80 mm OD and 21 mm width (1.378 × 3.15 × 0.827 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 83.5 kN, C0 71 kN, Pu 8.65 kN, grease limiting speed 8,100 r/min, oil 11,500 r/min, mass about 483 g. It is open, with the EA high-capacity 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. NF307EA 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. This page's bearing carries the EA pressed-steel-cage execution.
Can NF307EA 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 NF307EA?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 46.2 mm, Ew 70.2 mm. The nominal bore/OD remain 35/80 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 8,100 r/min grease / 11,500 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.