NU319-NTN bearing: complete specifications & equivalents
The NU319-NTN is a ISO 15 radial bearing sized 95 x 200 x 45 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 95 mm |
| Outer diameter D | 200 mm |
| Width B | 45 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 287 kN |
| Basic static load rating C0 | 289 kN |
| Fatigue load limit Pu | 31.5 kN |
| Limiting speed (mechanical) | 3400 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 5990 g |
| Manufacturer designation | NTN NU319 |
| 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 | 3.74 in |
|---|---|
| Outer diameter D | 7.874 in |
| Width B | 1.772 in |
| ISO bore code | 19 |
| Radial section height (D−d)/2 | 52.5 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) | 17 of 34 |
| Bore above smallest NU300-series size | 78 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| NU319 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 95×200×45 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 NU319-NTN model number is decoded
NTN lists NU319 on the 95×200 mm envelope, 45 mm wide: a line-contact radial bearing with a pressed sheet-steel cage and a grease limiting speed of 3,400 r/min. Numbering ties NU319 to its envelope: type code NU, series NU300, 95 mm bore; the 200×45 mm outline therefore swaps dimensionally with other ISO 15 bearings of the same code, though rib arrangements differ by prefix. Minimum radial load matters: an unloaded NU319 at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. Thermal planning around the 3,400 r/min grease ceiling should include the cage type (a pressed sheet-steel cage) and oil-flow option to 4,000 r/min for continuously high-duty 95 mm positions. Housing and shaft fillets must clear the ring chamfers of NU319; an oversized radius locks the ring on its face and tilts the 45 mm-wide seat.
Typical equipment & failure modes
Common applications
- marine gearbox and deck-machinery shafts
- large electric-motor and generator rotors
- cement and mining conveyor drive pulleys
- heavy industrial gearbox and reducer shafts
Known failure patterns
- roller smearing (microwelding) at start-up before the oil film builds under insufficient radial load
- 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
- hard-particle indentation of raceways in unfiltered oil or open arrangements
- brinelling from static overload or impact during handling
Selection pitfalls — read before you substitute
- Induction-heat the 95 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 200 mm raceway.
- Open NU319 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 95 mm contact.
- The 52.5 mm section at 95 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 45 mm-wide cavity.
- Do not replace NU319 with a deep-groove ball bearing on rating alone: line contact gives 287 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
- Do not replace NU319 with a deep-groove ball bearing on rating alone: line contact gives 287 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 287/289 kN ratings, 31.5 kN Pu and 5990 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NU319 (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 NU319?
NU319 is an NTN NU single-row cylindrical roller bearing to ISO 15: 95 mm bore, 200 mm OD and 45 mm width (3.74 × 7.874 × 1.772 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 287 kN, C0 289 kN, Pu 31.5 kN, grease limiting speed 3,400 r/min, oil 4,000 r/min, mass about 5990 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. NU319 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. NU319 is supplied in the standard open execution shown in the table.
Can NU319 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 NU319?
Fw is the inner sub-assembly raceway/roller-set envelope diameter and Ew the outer-ring raceway diameter printed for geometric checks: Fw 121.5 mm, Ew 173.5 mm. The nominal bore/OD remain 95/200 mm; Fw/Ew describe the rolling-contact path, and speeds still run to 3,400 r/min grease / 4,000 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.