N320 bearing: complete specifications & equivalents
The N320 is a ISO 15 radial bearing sized 100 x 215 x 47 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 100 mm |
| Outer diameter D | 215 mm |
| Width B | 47 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 330 kN |
| Basic static load rating C0 | 335 kN |
| Fatigue load limit Pu | 36 kN |
| Limiting speed (mechanical) | 3300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 7320 g |
| Manufacturer designation | NTN N320 |
| 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 & N300-series range
| Bore d | 3.937 in |
|---|---|
| Outer diameter D | 8.465 in |
| Width B | 1.85 in |
| ISO bore code | 20 |
| Radial section height (D−d)/2 | 57.5 mm |
| Smallest bore in N300-series | 17 mm |
| Largest outer diameter in N300-series | 580 mm |
| Width range across N300-series | 14–108 mm |
| Bore position in N300-series (smallest first) | 18 of 33 |
| Bore above smallest N300-series size | 83 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| N320-ECP | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 100×215×47 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 N320 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, N320 appears as a 100 mm bore single-row cylindrical roller bearing (330 kN C / 335 kN C0) with a pressed sheet-steel cage, listed to the ISO 15 boundary plan. Reading the code: N for the separable-outer-ring type, then the ISO 15 diameter/width series and the bore code — ×5 = 100 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. Equivalent-load planning treats N320 as a pure radial bearing: keep P below 330 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. Housing and shaft fillets must clear the ring chamfers of N320; an oversized radius locks the ring on its face and tilts the 47 mm-wide seat.
Typical equipment & failure modes
Common applications
- rolling-mill auxiliary drive shafts
- crusher and vibrating-screen drive shafts
- marine gearbox and deck-machinery shafts
- large electric-motor and generator rotors
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
- fretting corrosion on a loose rotating shaft seat
- rolling-contact fatigue after the catalogue L10 life is exceeded
Selection pitfalls — read before you substitute
- Induction-heat the 100 mm inner ring (max 120 °C) and mount it before fitting the outer ring; the ring mass makes square guidance essential — driving through the rollers brinells the 215 mm raceway.
- The 47 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 100 mm inner ring.
- Do not replace N320 with a deep-groove ball bearing on rating alone: line contact gives 330 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 57.5 mm section at 100 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 47 mm-wide cavity.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 330/335 kN pair here belongs to N320 as printed, not to the bare size.
- The 330/335 kN ratings, 36 kN Pu and 7320 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for N320 (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 N320?
N320 is an NTN N single-row cylindrical roller bearing to ISO 15: 100 mm bore, 215 mm OD and 47 mm width (3.937 × 8.465 × 1.85 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 330 kN, C0 335 kN, Pu 36 kN, grease limiting speed 3,300 r/min, oil 3,800 r/min, mass about 7320 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. N320 is two integral ribs on the inner ring and a ribless separable outer ring — equivalent float behaviour with the separable ring on the housing side.
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. N320 is supplied in the standard open execution shown in the table.
Can N320 take axial load and locate a shaft?
the N design is non-locating like NU but floats with the separable outer ring in the housing. Provide axial location with an adjacent locating bearing (angular-contact, deep-groove or a paired NJ/NUP set).
What do Fw and Ew mean for N320?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 129.5 mm, Ew 185.5 mm. The nominal bore/OD remain 100/215 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 3,300 r/min grease / 3,800 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.