Buy Cylindrical Roller Bearings Online in Australia
Cylindrical Roller Bearing Selection — Quick Reference
Cylindrical roller bearings handle HEAVY RADIAL LOADS — line contact vs ball point contact = higher capacity. NU + NJ + NUP series. Gearboxes + electric motors + machine tool spindles.
| Series | Configuration | Best For |
|---|---|---|
| NU Series | No fixed axial location (floating) | Free-end bearing position — thermal expansion |
| NJ Series | One-way axial location | Locating bearing — light axial load one direction |
| NUP Series | Two-way axial location (removable flange) | Locating bearing — light axial load both directions |
Critical: Cylindrical roller bearings carry NO or LIMITED axial load — NU carries none, NJ/NUP carry limited. Pair with a deep groove or angular contact bearing at the fixed end for full axial location. Higher radial capacity than equivalent-size ball bearings — line contact spreads load. Brands: NACHI, SKF, NSK, NTN, Koyo. Companion: bearings, deep groove ball bearings, spherical roller bearings.
Cylindrical Roller Bearings
Cylindrical roller bearings use cylindrical rollers in line contact with the inner and outer raceways rather than the point contact of a ball bearing, giving them significantly higher radial load capacity for a given size. AIMS Industrial stocks NACHI cylindrical roller bearings across the NU, NJ and NUP series for gearbox, electric motor and machine tool applications.
NU, NJ and NUP — what's the difference
The three series differ in how they handle axial (thrust) load:
- NU series — no flange on the inner ring, so the bearing has no fixed axial location. This makes it the correct choice for the "floating" bearing position in a shaft system, where thermal expansion of the shaft needs to be accommodated without inducing axial preload.
- NJ series — one flange on the inner ring, giving one-way axial location. Used as the locating bearing where a light axial load needs to be constrained in one direction only.
- NUP series — flanges on both sides with a removable outer flange ring (the "L" ring), giving two-way axial location. Used as the locating bearing where light axial load needs constraining in both directions.
Why choose cylindrical roller over ball bearings
Line contact between the roller and raceway spreads load over a larger contact area than the point contact of a ball bearing, giving cylindrical roller bearings substantially higher radial load capacity for the same bore size. This makes them the standard choice in gearboxes, electric motors and machine tool spindles where radial loads are high but axial loads are low or absent.
Locating and floating bearing arrangement
Because cylindrical roller bearings carry no or only limited axial load depending on series, they're typically paired with a deep groove ball bearing or angular contact bearing at the opposite end of the shaft to provide full axial location. This locating/floating arrangement lets the shaft expand thermally along its length without inducing internal preload that would shorten bearing life.
NACHI quality
NACHI is one of Japan's major bearing manufacturers, with a reputation for precision manufacturing and consistent quality across its bearing range. AIMS Industrial has stocked NACHI bearings for Australian industry for decades.
Expert Support: Contact our team or request a quote — we'll help size and specify the right cylindrical roller bearing for your application.
People Also Ask — Cylindrical Roller Bearings
What's the difference between NU, NJ and NUP cylindrical roller bearing series?
NU has no flange on the inner ring and no fixed axial location, making it the floating-position bearing. NJ has one flange, giving one-way axial location. NUP has flanges on both sides with a removable outer flange ring, giving two-way axial location.
Why do cylindrical roller bearings carry higher radial loads than a ball bearing the same size?
The roller sits in line contact with the raceway rather than the point contact of a ball bearing, spreading the load over a larger contact area and giving substantially higher radial load capacity for the same bore size.
Why does an NU cylindrical roller bearing need a second bearing at the other end of the shaft to fully locate it?
An NU bearing has no flange to carry axial load on its own, so it's paired with an angular contact or radial-contact bearing at the opposite shaft end to provide full axial location, while the NU end floats to accommodate thermal expansion along the shaft.
Which cylindrical roller bearing series should I use where I need to constrain axial load in both directions?
The NUP series — its removable outer flange ring on both sides gives two-way axial location, constraining light axial load in either direction.