NU313EA bearing: complete specifications & equivalents
The NU313EA is a ISO 15 radial bearing sized 65 x 140 x 33 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 65 mm |
| Outer diameter D | 140 mm |
| Width B | 33 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 213 kN |
| Basic static load rating C0 | 191 kN |
| Fatigue load limit Pu | 23.1 kN |
| Limiting speed (mechanical) | 4600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2200 g |
| Manufacturer designation | NTN NU313EA |
| 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 & NU300-series range
| Bore d | 2.559 in |
|---|---|
| Outer diameter D | 5.512 in |
| Width B | 1.299 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 37.5 mm |
| Smallest bore in NU300-series | 17 mm |
| Largest outer diameter in NU300-series | 620 mm |
| Width range across NU300-series | 14–109 mm |
| Bore position in NU300-series (smallest first) | 11 of 34 |
| Bore above smallest NU300-series size | 48 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NU313EA | 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 NU313EA model number is decoded
For pure radial duty on a 65 mm shaft NTN supplies NU313EA: two integral ribs on the outer ring and a ribless, separable inner ring; the open execution is rated 4,600 r/min on grease and 6,500 r/min on oil. The leading NU defines the rib arrangement (outer ring ribbed, inner ring ribless); the dimension-series digits and the two-digit bore code resolve to 65 mm, with 140 mm OD and 33 mm width from the ISO 15 general plan. Line contact between rollers and raceways gives NU313EA high radial capacity but no tolerance for misalignment: beyond roughly 3–4 arc-minutes the roller ends edge-load and fatigue accelerates. Equivalent-load planning treats NU313EA as a pure radial bearing: keep P below 213 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 NU313EA.
Typical equipment & failure modes
Common applications
- cement and mining conveyor drive pulleys
- heavy industrial gearbox and reducer shafts
- large pump, turbine and compressor rotors
- rolling-mill auxiliary drive 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
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- edge loading from shaft deflection beyond the 3–4 arc-minute alignment limit
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- Induction-heat the 65 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 140 mm raceway.
- Wide (22/23) and light (10/49) executions at 65 mm bore share bore but not OD/width; check the full NU300 series code before substituting, because housing and shoulder geometry will not interchange.
- If the shaft must be located both ways, do not use NU313EA alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
- Open NU313EA units need application-supplied sealing and a defined lubricant schedule; film thickness is the first failure mode for line contact when viscosity drops at the 65 mm contact.
- Wide (22/23) and light (10/49) executions at 65 mm bore share bore but not OD/width; check the full NU300 series code before substituting, because housing and shoulder geometry will not interchange.
- The 213/191 kN ratings, 23.1 kN Pu and 2200 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NU313EA (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 NU313EA?
NU313EA is an NTN NU single-row cylindrical roller bearing to ISO 15: 65 mm bore, 140 mm OD and 33 mm width (2.559 × 5.512 × 1.299 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 213 kN, C0 191 kN, Pu 23.1 kN, grease limiting speed 4,600 r/min, oil 6,500 r/min, mass about 2200 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. NU313EA is two integral ribs on the outer ring and a ribless, separable inner ring — a non-locating bearing that lets the shaft float axially.
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 NU313EA take axial load and locate a shaft?
the NU design carries no axial load and floats axially on both sides. 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 NU313EA?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 82.5 mm, Ew 124.5 mm. The nominal bore/OD remain 65/140 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 4,600 r/min grease / 6,500 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.