Determination of the Reliability Indicator According to the Technical Condition of the Elements of Contact Pairs

The assessment of the effectiveness and economic feasibility of using technical products over time is their reliability, which is predicted at the design stage. The technical task of predicting the required level of reliability should be considered from the perspective of the functional state of certain elements and their mating under specified operating conditions. The external conditions and the response of the elements to them determine the characteristics of changes in the parameters of the technical condition, which should be chosen from the point of view of analyzing the physics of the processes leading to failure. In most cases, contact pairs, including sliding friction pairs with periodic impacts, are subject to wear during operation, therefore, one of the parameters of their working condition is their geometric dimensions, which decrease in time determines the rate of the parameter change from its initial to the limiting value. The construction of this functional dependence allows determining the average value of the parameter at any time, control the achievement of its pre-failure value and, as a result, predict failure. The construction of the curve of change rate of the parameter determining the workable state of the contact pair in accordance with the approaches presented in the paper is only the first stage of reliability predicting. No less difficult is the stage of choosing a material that provides a given level of reliability.