Correctly grasp the use of bearings in machinery parts and conditions of use and environmental conditions is to select the appropriate bearing the premise. Whom, the following aspects need to obtain data and information: 
 (1) the function and structure of mechanical devices 
 (2) the use of parts of bearings 
 (3) bearing load (size, direction) 
 (4) rotational speed 
 (5) vibration, shock 
 (6) Bearing temperature (ambient temperature, temperature rise) 
 (7) the surrounding atmosphere (corrosion, cleaning, lubrication)