NJ310EA bearing: complete specifications & equivalents
The NJ310EA 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 NJ310EA |
| 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 & NJ300-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 NJ300-series | 17 mm |
| Largest outer diameter in NJ300-series | 580 mm |
| Width range across NJ300-series | 14–108 mm |
| Bore position in NJ300-series (smallest first) | 8 of 33 |
| Bore above smallest NJ300-series size | 33 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NJ310EA | 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 NJ310EA model number is decoded
NJ310EA belongs to the NTN cylindrical roller range in NTN Ball and Roller Bearings CAT.No.2203E, under the ＊ ULTAGE new-generation specification: line-contact rollers between ground raceways for a 130 kN dynamic rating in the 50 mm bore. Reading the code: NJ for the one-direction-locating type, then the ISO 15 diameter/width series and the bore code — ×5 = 50 mm (00–03 use the 10/12/15/17 exception table). 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. The 2.6 kN-per-mm-bore figure (130 kN over 50 mm) lets a NJ310EA interchange candidate be screened quickly against the same-envelope ball or roller alternatives. 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
- industrial gearbox input and output shafts
- medium electric-motor and generator shafts
- pump and compressor crankshafts and rotors
- machine-tool gearbox and spindle radial sets
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
- 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 NJ310EA.
- Wide (22/23) and light (10/49) executions at 50 mm bore share bore but not OD/width; check the full NJ300 series code before substituting, because housing and shoulder geometry will not interchange.
- The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 130/113 kN pair here belongs to NJ310EA as printed, not to the bare size.
- Open NJ310EA 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 50 mm contact.
- The NJ rib arrangement is not interchangeable with another prefix on the same 50 mm seat: inner ring two ribs + one outer rib. 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 NJ310EA (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 NJ310EA?
NJ310EA is an NTN NJ 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. NJ310EA is two integral ribs on the inner ring and one rib on the outer ring — it locates the shaft in one axial direction.
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 NJ310EA take axial load and locate a shaft?
the NJ design accepts axial load in one direction and provides one-way shaft location. For two-direction location use an NUP execution or an NJ pair with loose rib rings.
What do Fw and Ew mean for NJ310EA?
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.