Determination of lifetime for railway carriages automatic coupler SA – 3
carriages automatic coupler. The loading of automatic coupler, predetermined by the weight of a train, train speed and railway relief, is time-dependent variable. By the calculation of strain stress state in the body of automatic coupler it was determined, that automatic coupler is under static, low cycle and high cycle loading. Therefore, to calculate lifetime of automatic coupler the dependencies for low cycle nonstationary stress limited loading, evaluating low cycle quasistatic and fatigue damages, has been proposed. To evaluate high cycle fatigue damage a linear law for the summation of loading cycles has been proposed. For low cycle damage summation a calculation method was proposed for the evaluation of fatigue and quasistatic damages created at one loading cycle, taking into account loading level and neglecting sequence of cycles. Therefore, working on calculations of automatic coupler for each specific case it is necessary to determine number of loading cycles at each loading level and calculate lifetime by presented in this work dependencies.