KNOWLEDGE

Cylindrical Roller Bearings Introduction

Cylindrical Roller Bearings

 

Basic Introduction:

Cylindrica roller bearing is radial rolling bearing. Cylindrical rollers and raceways are linear contact bearings.
Cylindrical roller bearings mainly bear radial load. The friction between the rolling element and the retaining edge of the ring is small, therefore, it is suitable for high-speed rotation.
According to whether the ring has ribs, it can be divided into single row bearings and double row bearings.
Single row bearings include NU, NJ, NUP, N, NF, and double row bearings include NNU and NN.

Features of cylindrical roller bearings:

1. The roller and the raceway are in line contact or under-line contact, with large radial bearing capacity. As a result, it is suitable for bearing heavy loads and impact loads.
2. The friction coefficient is small, which is suitable for high speed, and the limit speed is close to the deep groove ball bearing.
3. N type and NU type can move axially. Therefore, it can adapt to the change of the relative position of shaft and housing caused by thermal expansion or installation error.
Moreover, it can be used as free end support.
4. The processing requirements for the shaft or the seat hole are relatively high. After users install bearings, the relative deflection of the outer ring axis should be strictly controlled to avoid contact stress concentration.
5. Users can separate inner ring and outer ring without difficulty.

Application of cylindrical roller bearings:

Cylindrical bearings are widely used on many applications.
For example, large and medium-sized electric motors, rolling stock, machine tool spindles, internal combustion engines, generators, gas turbines, gearboxes, rolling mills, vibrating screens, lifting and transporting machinery, etc.

Bearing Construction:

1. N0000 and NU0000 type cylindrical roller bearings which without ribs on the outer ring and inner ring can load large radial loads. Moreover, N0000 and NU0000 type bearings have high limit speed and cannot accept axial loads.

2. NJ0000 and NF0000 cylindrical roller bearings with ribs on both inner and outer rings can restrain the axial displacement of the shaft or housing in one direction. Therefore, NJ0000 and NF0000 type cylindrical roller bearings can accept small unidirectional axial loads.

3. NU0000+HJ0000, NJ0000+HJ0000, NUP0000 type bearings can restrain the axial displacement of the shaft or the shell in the axial clearance area of bearing. And NU0000+HJ0000, NJ0000+HJ0000, NUP0000 type bearings can accept small two-way axial load.