Effect of Surface Roughness on Rolling Element Bearing

A large number of bearings can be found all around us. Take automobiles, for example, there are 100 to 150 bearings in a typical car. Without bearings, the wheels would rattle, the transmission gear teeth wouldn't be able to mesh, and the car wouldn't run smoothly. Bearings are not used only in vehicles, but in all kinds of machinery such as trains, airplanes, washing machines, refrigerators, air conditioners, vacuum cleaners, photocopy machines, computers, satellites, etc. Generally, the machine fails due to bearing faults, misalignment, coupling wear, unbalance, ring wear, leakage, etc. Studies show that bearing failures account for about 40% of all machine failures. Ball and roller bearings are called rolling element bearings and they are essential parts of rotating machinery. They are used to support the load and allow the relative motion of shafts. Rolling element bearings work under different conditions and frequently under heavy loadings generated in the machinery and they are subjected to time and space-varying loads and speeds.