Active Systems. Wear-Fatigue Damage

Abstract

The active system is any mechanical system that reacts to and transmits the alternating workload with simultaneous occurrence of the friction process with its any manifestation: in sliding, rolling, slippage, impact, etc. Some typical examples of the system are the following: the shaft /hub (of the gear wheel, the flywheel, etc.) with the stationary or running fit (molded, keyed, splined and other joints); the crankpin /connecting rod with the sliding bearing (bolted, riveted or threaded connectionsthat transmit cyclic loading); the wheel /rail and many others. As a rule, they are the most essential and widely used units of modern machinery and equipment. Complex wear-fatigue damage (WFD) is typical for them with the main types being mechano-sliding, mechano-rolling, mechano-erosion and fretting fatigue. Table 2.1 gives the definitions of these types of WFD in respect to the typical examples of the active systems.

Problems are more variable than solutions. Solutions may become obsolete, while problems remain. Niels Bohr