R. Guncheva

A mathematical model for investigating and optimizing the periodicity of machine maintenance by reliability limit characteristics
N. Ivanova
Department of Mechanical Engineering, Faculty of Techniques and Technologies, Trakia University, 8600 Yambol, Bulgaria

(Manuscript received 11 March 2025; accepted for publication 4 May 2025)

Abstract. In this publication, the influence of the main parameters on the specific costs and frequency diagnosis is investigated. The known mathematical models for optimization of the time of diagnostics of the machine elements (tractors, cars, etc.) are created on the basis of the reliability theory, the criterion for optimization is techno-economic. The aim of the research work is to propose a new mathematical model to optimize the frequency of maintenance of machines by limit reliability, function-limit, work beyond limit resources, as the limit resource is one of the main characteristics determining the efficiency of the object and it is necessary to determine its optimal value in two cases: in multiple maintenance and one current repair. We found that as the replacement cost (C2) increases, the TO frequency increases in a linear relationship, and the influence of different mathematical model parameters on the optimal maintenance frequency of the machines is considered.