1)Spaces

Bearings to be used

2)Load
　

Load capacity ,its direction and nature
The load capacity of the bearing is expressed with rated load with the values listed in Bearing Dimension List

lFor suitable bearings it is important to select as per load capacity, load direction(racial or axial/ single or double) vibration& impact degrees.

lGenerally speaking , the radical load capacity of the bearing with same inner diameter increase in following sequence:

deep groove ball bearings < angle contact ball bearings < cylindrical roller bearings < cone roller bearings < center adjustable roller bearings

3)Speed

The bearing adaptableto mechanical rotation

the limit value basis of the bearing rotating speed is expressed with revolution speed limit with the values listed in Bearing Dimension List

lThe rotation limit does not only depend on the bearing type but also on its sizes, retainer, precision grade, load conditions & lubrication. Thence these factors must be taken into account too.

lFollowing bearing are suitable for high speed rotation.

deep groove ball bearings.angle contact ball bearings.cylindrical roller bearings

4)Rotation precision

The type with necessary rotation precision

the precision of size & and rotation is now standardized by ISO.

lThe bearings of grade 5 and/or up are suitable for high speed rotation and low friction requirements for main shaft of machine tools, gas turbine engines & controlling machinery

lUsually the following bearings are used:

deep groove ball bearings. angle contact ball bearings.cylindrical roller bearings

5)Rigidity

The types with necessary rigidity

Under load, there will be elastic deformation in the contacting parts between rolling bodies and tray.
High rigidity means less elastic deformation resulted.

l         When used in machine tool main shaft or the last speed reduction unit of the car, both rigidities must be raised.

l         Less deformation will be resulted on roller bearing that of the ball bearings.

l         Pre-tension on the bearing (negative clearance) will increase the rigidity of the angle contact ball bearings and cone roller bearings.

6）Relative slope between inner & outer rings
 

Select the bearings suitable for such conditions by analyzing the factors causing the rotation slope between two surfaces of inner & outer rings.

the permissive inclining angle (or adjustable angle) of the bearing is listed in the explanation before the Bearing Dimensional Lists of various types.

l         The bearing will be damaged by the inner load if the rotation inclination between the inner and outer rings is too great. So selecting the special bearing type which may bear this slope is necessary.

l         Generally speaking, the permissible inclining angle (or center adjustable bearing angle) increases in following sequence.

cylindrical roller bearings< cone roller bearings< deep groove ball bearings< angular contact ball bearings< center adjustable roller (ball) bearings

7）Mounting & dismounting

The times of dismounting for periodical checks & the dismounting ways
 

Cylindrical roller bearing , needle bearing & cone roller bearing are more convenient for frequent dismounting because the inner ring is separable form the outer ring.