The rolling body is the centripetal rolling bearing of cylindrical roller.
The inner structure of cylindrical roller bearing adopts rollers to be arranged in parallel, and there is a spacer or isolation block between rollers, which can prevent the tilt of rollers or friction between rollers, and effectively prevent the increase of rotating torque. 

Single row cylindrical roller bearings: Single row cylindrical roller bearings are separable bearings for easy installation and disassembly. Both rings can be fitted tightly. Modified contact lines between rollers and raceways can reduce stress concentration. 
 

N type:
The inner ring has two integral flanges and the outer ring is without flanges. Axial displacement of the shaft with respect to the housing can be accommodated in both directions within the bearing itself. The bearings are therefore used as non-locating bearings.
NU type:
The outer ring of bearings of the NU design has two integral flanges and the inner ring is without flanges. Axial displacement of the shaft with respect to the housing can be accommodated in both directions within the bearing itself.
NJ type:
The outer ring has two integral flanges and the inner ring one integral flange. The bearings are therefore suitable for the axial location of a shaft in one direction.
NF type:
The outer ring has one integral flange and the inner ring two integral flanges.
NUP type:
The outer ring has two integral flanges and the inner ring one integral flange and one non-integral flange in the form of a loose flange ring. The bearings can be used as locating bearings, i.e. they can provide axial location for a shaft in both directions.
RN type:
No outer ring and the inner ring two integral flanges.
NN type:
NN type bearing without ribs on outer ring,there is a wall in the midel of between both sides of inner ring. It can make shaft relative bearing between the axial displacement generated in both directions.
 

Characteristics: 
1.Roller and raceway are in line contact or downline contact, radial bearing capacity is large, suitable for bearing heavy load and impact load.  
2.Small friction coefficient, suitable for high speed, limit speed close to deep groove ball bearings.  
3.N type and NU type can be moved in axial direction, can adapt to the change of the relative position between the shaft and the shell caused by thermal expansion or installation error, can be used as free end support.  
4.The processing requirements for shafts or seat holes are high. After bearing installation, the relative deviation of the outer ring axis should be strictly controlled to avoid contact stress concentration.  
5.The inner ring or outer ring can be separated, easy to install and disassemble.

Application:
Large and medium-sized electric motors, rolling stock, machine tool spindles, internal combustion engines, generators, gas turbines, reduction boxes, rolling mills, vibrating screens and lifting and transportation machinery, etc.