NU207 bearing: complete specifications & equivalents
The NU207 is a ISO 15 radial bearing sized 35 x 72 x 17 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | Generic ISO interchange (unbranded) |
| Bore diameter d | 35 mm |
| Outer diameter D | 72 mm |
| Width B | 17 mm |
| Seal / shield | open |
| Internal clearance | CN / C3 / C4 available |
| Tolerance class | P0 |
| Cage | steel |
| Operating temperature | -30 to +120 °C |
| Mass (geometry estimate) | 270 g |
| Standard | ISO 15 |
| Catalog version | iso15-crb-geometry |
| Last verified | 2026-09-24 |
Source: ISO 15 boundary-dimensions standard · extracted 2026-09-24
Standard-interchange bearing: dimensions per ISO 15; CN clearance, P0 tolerance and a stamped-steel cage are catalogue defaults unless the supplier states otherwise, and mass is a geometry-derived estimate. Brand catalogue load ratings and limiting speeds for NU207 are being backfilled — use the inquiry form for certified values.
Dimensions in inches & NU200-series range
| Bore d | 1.378 in |
|---|---|
| Outer diameter D | 2.835 in |
| Width B | 0.669 in |
| ISO bore code | 07 |
| Radial section height (D−d)/2 | 18.5 mm |
| Smallest bore in NU200-series | 20 mm |
| Largest outer diameter in NU200-series | 180 mm |
| Width range across NU200-series | 14–34 mm |
| Bore position in NU200-series (smallest first) | 4 of 17 |
| Bore above smallest NU200-series size | 15 mm |
Cross references & equivalents
No verified interchange data yet. Send an inquiry and our team will confirm equivalents manually.
How the NU207 model number is decoded
In the NU200-series (ISO 15 dimension series) the leading NU marks a single-row cylindrical roller: the outer ring has two integral shoulders and the inner ring none, so the inner-ring/roller assembly floats axially both ways and the bearing locates radially only; the last two digits of NU207 are bore code 07 = 35 mm (code × 5 from 04 upward). The ISO 15 envelope is 72 mm outside diameter and 17 mm width — 1.378 × 2.835 × 0.669 in, with a 18.5 mm radial section height. Straight cylindrical rollers give line contact for high radial capacity at low friction, with no self-alignment; catalogue practice for a rotating inner ring is a k5 shaft seat, H7 housing and C3 clearance. NJ adds one inner shoulder (one-direction location), NUP two shoulders (full location); E denotes a reinforced roller complement — verify against the actual load direction.
Typical equipment & failure modes
Common applications
- fractional electric motor armatures
- two-wheeler and appliance transmissions
- small pump and fan rotor shafts
- textile and packaging machinery rolls
- light conveyor drive shafts
Known failure patterns
- thermal seizure when an interference fit plus hot running removes all residual C3 clearance
- roller and raceway smearing when a lightly loaded NU row skids at start-up or below the minimum load
- edge loading and rib spalling from shaft-to-housing misalignment — cylindrical rollers run on line contact and cannot self-align
- roller-end and flange scoring when an NU bearing is forced to locate axially; only NJ/NUP designs carry thrust at the shoulders
- cage fatigue and fracture after sustained over-speed with marginal lubrication
Selection pitfalls — read before you substitute
- At 35 mm bore the small NU207 commonly shares a gearbox bore with a 6-series deep-groove row; do not substitute by envelope alone — the cylindrical roller carries far more radial load but no thrust, so any helical-gear axial force needs a paired angular-contact or NJ locating row.
- The NU2 light series at 35 mm bore (72×17 mm) is the default gearbox cylindrical row; on the same bore an NU307 is larger with a much higher rating — do not replace a failed NU307 with an NU207 without re-rating L10 life.
- Before fitting NU207, machine the 35 mm shaft seat and 72 mm housing bore with a relief or undercut so nothing bridges the chamfer; the separable rings only carry load when their full faces abut, and a large fillet pinches the 18.5 mm radial section.
- With a separable NU207, mount the inner-ring/roller assembly on the shaft and the plain outer ring in the housing independently; check that the outer ring is free to float the specified amount after closing the housing — a pinched outer ring turns the floating bearing into an accidental locating one.
- Relubricate NU207 with the shaft turning so fresh grease or oil reaches the full 17 mm roller length; grease forced into a stationary row packs the entry and leaves the far side of the 35 mm bore starved.
- At high speed, oil lubrication or a low-friction cage beats a grease-packed stamped-cage NU207: line-contact rollers churn grease hard, so follow the catalogue speed factor (n × dm) and preload the oil jet for sizes above the 35 mm bore band rather than extrapolating ball-bearing practice.
- Choose the ring design for the locating task: a plain NU207 (NU) floats axially in both directions and is the classic non-locating bearing of a two-bearing shaft; NJ locates in one direction, and NUP (or NJ + HJ angle ring) locates in both — do not use an NU row where the shaft needs axial location.
Frequently asked questions
What are the dimensions of an NU207 cylindrical roller bearing?
An NU207 single-row cylindrical roller bearing per ISO 15 has a 35 mm bore, 72 mm outer diameter and 17 mm width (1.378 × 2.835 × 0.669 in), a 18.5 mm radial section and roughly 270 g geometry-based estimated mass; catalogue masses vary with cage and E design.
How does the NU207 bore code work?
The letters give the ring/shoulder design (NU = axially free, NJ = one inner shoulder, NUP = two shoulders) and the last two digits are bore code 07: 07 × 5 = 35 mm. The 72 mm OD and 17 mm width come from the ISO 15 dimension series (NU200), which shares its boundary plan with the 6-series deep-groove envelopes.
What is the difference between NU, NJ, N and NUP designs?
NU (like the NU207) has a shoulderless inner ring and floats axially in both directions; NJ has one integral inner-ring shoulder and locates the shaft in one direction; N has two inner shoulders and a shoulderless outer ring (mirror of NU); NUP adds a second, loose shoulder so the inner ring locates in both directions. Select by the shaft locating scheme, not by load rating — the envelopes are identical.
Can an NU207 take axial load or misalignment?
No thrust in the NU design: any sustained axial force scores the roller ends and ring flanges, so locate the shaft with an NJ/NUP row, a paired angular-contact bearing or a deep-groove row elsewhere. Misalignment is likewise not tolerated — line contact between cylindrical rollers and raceways edges under even small angular errors; use a spherical roller bearing where shaft deflection or housing misalignment is expected.
What does the E suffix mean and which clearance should be ordered?
E (as in NU207E) is the reinforced design: larger/optimised rollers raise the basic load rating over the basic designation in the same 35×72×17 mm envelope. For clearance, C3 is the usual default with an interference fit on a rotating inner ring because fit and thermal growth reduce residual play; use CN mainly for loose floating outer-ring mounts and C4 for hot or vibratory duty.
Reviewed & verified by the MPN Base engineering desk against source catalog iso15-crb-geometry on 2026-09-24. Read our editorial & correction policy.