1. Loading characteristics of needle roller bearings for automobiles

 

(1) The contact loads and stresses of rotating rings and rolling bodies change when they pass through all points of the bearing area, while the contact loads and stresses at each point of contact are characterized by a pulsating cycle, and they are not loaded in the non-bearing area;
(2) For each point of the fixed ring, the load and stress are different, while the contact load and stress at each point show the same characteristics of pulsating cycle, but the magnitude is different.
For deep groove ball bearings (6 classes): F0= (4.37/Z) Fr.
2. Failure forms of needle roller bearings for automobiles
(1) Bearings in normal operation (10 r/min)
(2) For bearings with stationary or low rotating speed (n≤ 10 r/min) or intermittent swing, & mdash; plastic deformation of inner and outer rings and rolling bodies;
(3) Inevitable friction and wear of inner and outer rings and rolling bodies;
3. Design criteria of needle roller bearings for automobiles
(1) For normal running bearings - mdash; & mdash; in order to prevent fatigue pitting corrosion, life calculation is carried out on the basis of fatigue strength calculation;
(2) For low-speed bearings, or bearings under continuous load or intermittent load without rotation, plastic deformation should be controlled, & mdash; & mdash; static strength calculation should be carried out;
(3) For high-speed running bearings-mdash; & mdash; besides life calculation, the limit speed of bearings should also be checked.