Some problems of increasing reliability and safe operation of heavy mining machines

Abstract

Abstract. In the work, the following rubber parts were subject to research: rubber-metal blocks (BMR) of a prismatic shape, rubber vibration isolators (VR) with a complex free surface shape, rubber-metal vibration isolators (VRM), as well as layered vibration isolators (VRMS). Their use in the design of vibration protection systems for heavy mining vibration machines (vibrating feeders, vibrating conveyors, mixers, etc.) is very relevant. To determine the parameters of rigidity, temperature of dissipative heating and durability of these parts of different configurations, the universally constructive-deformation parameter ( was used. On the basis of the energy criterion, the basic relationships were obtained, which make it possible to determine the indicators of the durability of the designed rubber parts. To determine quantitative indicators of reliability of the vibration isolators under the study, a set of actions was planned to register their failure parameters. The Weibull’s law was adopted as the main distribution law. The goal was to determine such reliability indicators as the probability of no-failure operation for time t, the value of ninety percent MTBF and the boundaries of the confidence interval, in which the actual value of the ninety percent MTBF of the tested rubber parts is located with a 90 % probability. The results of the registration of parameters during testing for the reliability of a batch of vibration isolators of the VRM type for about 16 years are given; received an array of data on failures and their operating time. The results of measurements of the values of the main physical and mechanical characteristics of vibration isolators are presented. The failure criterion of vibration isolators was taken as their main parameters exceeded the permissible values. The results showed that the hypothesis of using the Weibull’s distribution law as a theoretical description of the occurrence of failures is confirmed. The obtained values of the quantitative indicators of the reliability of rubber vibration isolators of elastic suspensions of heavy mining machines are confirmed by theoretical calculations and experimental studies.