Rolling bearings are essential machine elements that ensure reliable operation of most types of machines and equipment. Without properly designed and working rolling bearings, most mechanical components and assemblies would not be able to function properly. Rolling bearing breakdown can manifest in several forms, with each form possessing its own set of causes and effects.
Excessive Heat
Heat buildup can cause breakdown within a rolling bearing, leading to degradation of the bearing surface and eventual bearing failure. Heat is usually generated from loads that are too heavy, poor lubrication, poor ventilation, or operating at excessive speeds. Rolling bearings can handle a certain amount of heat but if the bearings are exposed to temperatures higher than the recommended operating conditions, the lubricant may start to decompose and the metal continues to heat up. Over time, the rolling element and contact surface may receive too much heat, resulting in pitting, scoring, or welding. The bearing surfaces may also crack and wear away until proper lubrication and cooling can be restored.
Vibration and Thrashing
Vibration and thrashing are common causes of rolling bearing breakdown. Vibration can lead to metal fatigue and wear of the bearing elements, resulting in decreased bearing life and possible bearing failure. Thrashing occurs when the rolling elements start to move out of their normal running paths as they are loaded, leading to eventual bearing failure. Thrashing can happen when the bearing is improperly installed, poorly lubricated, running at excessive speeds, or if there is an excessive number of rolling elements for the design of the bearing.
Impact Damage
Impact damage is caused when the bearing components come into contact with foreign objects or debris, resulting in pitting and scoring of the contact surfaces. Impact damage can also occur when large amounts of shock or vibration is imparted on the bearing as well. For example, sudden unexpected acceleration or deceleration, as well as potholes or rough roads can cause impact damage to the bearing.
Corrosion
Corrosion and rust can lead to premature breakdown of a rolling bearing. There are several causes of corrosion, including poor deposit management, exposure to moisture, exposure to chemicals and acids, and insufficient lubrication. Corrosion can cause pitting and grooving on the bearing surface, leading to increased friction and eventual bearing failure. Proper storage of the bearing, as well as proper lubrication can minimize corrosion and protect the bearing from damage.
Misalignment
Misalignment of the bearing can cause bearing damage, especially if several bearings are used in the same assembly. Misalignment of the bearings can lead to increased friction, as the rolling elements move out of their normal paths. This, in turn, generates heat and increases the contact stresses, leading to bearing failure. Proper installation and alignment of the bearing should be ensured before operation in order to minimize bearing damage and ensure proper and smooth operation.
Contamination
Contamination of the bearing can lead to a decrease in its service life, as contaminants can cause wear of the contact surfaces and lead to the creation of debris. The most common contaminants are abrasive particles, such as dust and dirt, as well as water and lubricants. Contaminants can enter the bearing through the inlet and seal, leading to pitting, scoring, oxidation, and wear of the bearing surface. Proper attention should be given to the maintenance of the bearing, as well as the cleanliness of the environment, to minimize the effects of contamination.
Rolling bearing breakdown can lead to decreased performance and eventual mechanical failure of the device or machine assembly. Proper attention must be given to the care and maintenance of the bearing, as well as the operating conditions, to ensure increased life expectancy and smooth operation of the bearing. To prevent bearing breakdown, manufacturers should ensure that the rolling bearing components are properly designed and selected for their respective applications, as well as that proper lubrication and environmental conditions are maintained.
