Common forms of fretting damage of deep groove ball bearings

Common forms of fretting damage of deep groove ball bearings. In fact, the fretting state of precision deep groove ball bearings is very complex. Generally, according to the simplified plane contact model and different relative motion directions, the fretting can be divided into four basic motion modes: tangential motion, radial motion, rolling fretting, and twisting fretting. In fact, the last three kinds of fretting often occur or occur in two or more fretting ways. The damage caused by fretting to precision deep groove ball bearings is mainly in three ways: fretting wear of deep groove ball bearings, fretting fatigue of deep groove ball bearings, and fretting corrosion of deep groove ball bearings. The fretting wear of precision deep groove ball bearing is caused by the relative displacement of contact surface caused by external vibration. The contact piece carries a large amount of local contact load, which leads to the wear of steel ball and raceway in precision deep groove ball bearing. Fretting fatigue of precision deep groove ball bearing refers to the fretting caused by bearing fatigue alternating stress, which leads to the damage of contact surface of precision deep groove ball bearing. Fretting corrosion of deep groove ball bearing refers to the damage of contact surface of precision deep groove ball bearing caused by the use of precision deep groove ball bearing in rain, corrosive gas and other environments under the action of corrosive medium. After the angular contact deep groove ball bearing is loaded with normal alternating load, a circular pit like fretting damage of "pseudo cloth indentation" is left on the inner and outer race raceways of the inner and outer precision deep groove ball bearings. The fretting wear on the outer ring slows down with the increase of load, the swing angle and the number of cycles. The joint deep groove ball bearing is subject to fretting wear during movement, which leads to the looseness or inaccurate positioning of the mechanical arm, thus reducing the quality and service life of the product.