Designing the content and scale of maintenance of machines and equipment by a priori and posterior reliability methods in considered crucial to reducing the cost of the machine's life cycle, maintaining high operational readiness and reducing the consewuences of failures.

In the presented paper, attention is paid to the analysis of the calculation methods of posterior reliablity for calculation indicators of reliability and to the use of hte specified Weibull model for realiability calculations.

The obtained results are further developed for models of optimal process calculations to perform scheduled maintenance interventions. Calculations of the other RAMS (reliability, availability, maintainability and safety) indicators that are critical to the design of an optimal engineering design with regard to maintenance and which do not receive sufficient attention in technical practice are also assessed.

This paper is supported by: VEGA 1/0766/15 Research of noise emissions sources in the railway transport and methods of their effective reduction.