Development of a repair technology for locomotive units on the basis of the theory of decision

Abstract

The operative condition of locomotives is maintained by the existing repair system; it consists of the following elements: strategy, organization and technology. This repair technology for units and aggregates is based on disassembling and elimination of defects, and it can be inappropriate. The actual technical condition of the nodes requires an individual approach in determining the volume and content of technological impact during the repair process. Therefore, the purpose of this work is to research the task of developing a repair technology for locomotive units, depending on their actual technical condition. As far as probability distribution functions of the operating condition of units are known, a repair technology is chosen under risky conditions. Therefore, the decision-finding problem is framed in the theory of decision terms. The analysis of the decision tree of the choice of repair technology for fuel injectors of a diesel locomotive demonstrated that at least four variants of technologies (strategies) were possible. Operational costs were taken as the evaluation criterion for the technological process. The pay-off matrix obtained does not have a saddle point; therefore, the problem of choice of the technology cannot be solved only strategically. It substantiates a need to use flexible, adaptive repair technologies which consider the actual technical state of each unit. For a known distribution of states for fuel injectors, the greatest gain with minimum risks is the repair technology of dismantling and reseating the worn-out parts. Application of the described approach at locomotive repair enterprises will allow for improvement of the quality of repair and reduction of costs.