NUP310EA bearing: complete specifications & equivalents
The NUP310EA is a ISO 15 radial bearing sized 50 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 | 50 mm |
| Outer diameter D | 110 mm |
| Width B | 27 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 130 kN |
| Basic static load rating C0 | 113 kN |
| Fatigue load limit Pu | 13.8 kN |
| Limiting speed (mechanical) | 5900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1120 g |
| Manufacturer designation | NTN NUP310EA |
| 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 & NUP300-series range
| Bore d | 1.969 in |
|---|---|
| Outer diameter D | 4.331 in |
| Width B | 1.063 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30 mm |
| Smallest bore in NUP300-series | 20 mm |
| Largest outer diameter in NUP300-series | 580 mm |
| Width range across NUP300-series | 15–108 mm |
| Bore position in NUP300-series (smallest first) | 7 of 32 |
| Bore above smallest NUP300-series size | 30 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NUP310EA | 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 NUP310EA model number is decoded
NUP310EA is the standard section of the NTN NUP300 dimension series for a 50 mm shaft — 130 kN of basic dynamic capacity in a 1120 g, open bearing. On the NTN nameplate NUP states which ring carries the ribs, which determines whether NUP310EA floats or locates; the numeric remainder is the ISO 15 series and 50 mm bore reference, not a fit or clearance instruction. NTN prints the raceway diameters for this size — Fw 65 mm and Ew 97 mm — the envelope inside the 50/110 mm bore/OD where the rollers actually run. Thermal planning around the 5,900 r/min grease ceiling should include the cage type (the EA high-capacity pressed sheet-steel cage) and oil-flow option to 8,300 r/min for continuously high-duty 50 mm positions. Heat the inner ring to max 120 °C for the 50 mm interference fit and support the ring face square during fitting; cocking over a keyway brinells the raceway before first rotation.
Typical equipment & failure modes
Common applications
- machine-tool gearbox and spindle radial sets
- material-handling drum and wheel shafts
- papermaking and printing auxiliary drives
- fan and blower rotor positions
Known failure patterns
- inner-ring raceway spalling from overload in the line-contact Hertzian zone
- pressed-steel cage pocket wear when rollers skid at light load or too-thin lubricant
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- 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 50 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 NUP310EA.
- The 27 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 50 mm inner ring.
- Do not replace NUP310EA with a deep-groove ball bearing on rating alone: line contact gives 130 kN radial capacity but the bearing only accepts small sustained axial guidance loads and misalignment tolerance is only 3–4 arc-minutes.
- The 27 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 50 mm inner ring.
- The NUP rib arrangement is not interchangeable with another prefix on the same 50 mm seat: inner ring two ribs + loose L-ring. Swapping NU for NJ changes axial location behaviour even though the 110×27 mm envelope matches.
- The 130/113 kN ratings, 13.8 kN Pu and 1120 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NUP310EA (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 NUP310EA?
NUP310EA is an NTN NUP single-row cylindrical roller bearing to ISO 15: 50 mm bore, 110 mm OD and 27 mm width (1.969 × 4.331 × 1.063 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 130 kN, C0 113 kN, Pu 13.8 kN, grease limiting speed 5,900 r/min, oil 8,300 r/min, mass about 1120 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. NUP310EA is the NJ rib arrangement plus a loose L-shaped rib ring on the inner ring — it locates the shaft in both axial directions.
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 NUP310EA take axial load and locate a shaft?
the NUP design provides two-direction axial location via its loose rib ring, for light/moderate thrust guidance. 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 NUP310EA?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 65 mm, Ew 97 mm. The nominal bore/OD remain 50/110 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 5,900 r/min grease / 8,300 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.