NUP305EA bearing: complete specifications & equivalents
The NUP305EA is a ISO 15 radial bearing sized 25 x 62 x 17 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 25 mm |
| Outer diameter D | 62 mm |
| Width B | 17 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Basic dynamic load rating C | 49 kN |
| Basic static load rating C0 | 37.5 kN |
| Fatigue load limit Pu | 4.55 kN |
| Limiting speed (mechanical) | 11000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 242 g |
| Manufacturer designation | NTN NUP305EA |
| 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 | 0.984 in |
|---|---|
| Outer diameter D | 2.441 in |
| Width B | 0.669 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 18.5 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) | 2 of 32 |
| Bore above smallest NUP300-series size | 5 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NUP305EA | 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 NUP305EA model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, NUP305EA appears as a 25 mm bore single-row cylindrical roller bearing (49 kN C / 37.5 kN C0) with the EA high-capacity pressed sheet-steel cage, listed to the ISO 15 boundary plan. The leading NUP defines the rib arrangement (inner ring two ribs + loose L-ring); the dimension-series digits and the two-digit bore code resolve to 25 mm, with 62 mm OD and 17 mm width from the ISO 15 general plan. The 17 mm width and 18.5 mm section put the NUP300 series in the standard section; wide 22/23 variants at the same bore change OD, width and heat generation and are not drop-in swaps. The 2.0 kN-per-mm-bore figure (49 kN over 25 mm) lets a NUP305EA interchange candidate be screened quickly against the same-envelope ball or roller alternatives. 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 NUP305EA.
Typical equipment & failure modes
Common applications
- two-wheeler and small-engine transmission shafts
- small pump and compressor rotor shafts
- appliance and office-machine drives
- agricultural PTO and implement gear shafts
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
- grease starvation and cage drag when relubrication intervals are extended past the grease life
- electrical pitting on VFD-driven motor shafts without grounding protection
- hard-particle indentation of raceways in unfiltered oil or open arrangements
Selection pitfalls — read before you substitute
- Small 25 mm-bore cylindrical rollers are skid-sensitive: ensure the radial load exceeds the minimum-load floor at operating speed, or the NUP305EA rollers smear even with correct grease.
- Do not replace NUP305EA with a deep-groove ball bearing on rating alone: line contact gives 49 kN radial capacity but the bearing only accepts small sustained axial guidance loads and misalignment tolerance is only 3–4 arc-minutes.
- The 17 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 25 mm inner ring.
- Open NUP305EA 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 25 mm contact.
- Open NUP305EA 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 25 mm contact.
- The 49/37.5 kN ratings, 4.55 kN Pu and 242 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NUP305EA (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 NUP305EA?
NUP305EA is an NTN NUP single-row cylindrical roller bearing to ISO 15: 25 mm bore, 62 mm OD and 17 mm width (0.984 × 2.441 × 0.669 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 49 kN, C0 37.5 kN, Pu 4.55 kN, grease limiting speed 11,000 r/min, oil 15,600 r/min, mass about 242 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. NUP305EA 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 NUP305EA 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 NUP305EA?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 34 mm, Ew 54 mm. The nominal bore/OD remain 25/62 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 11,000 r/min grease / 15,600 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.