Generalised Gamma Distribution in the Corrective Maintenance Prediction of Homogeneous Vehicles

Vehicles of municipal transportation are complex, multi-component technical objects that require high reliability and safety level and, on the other hand, ensure high level of quality and low cost of service. These requirements and limitations need reliable information for making reasonable decisions. Operators tend to use advanced information concerning daily usage, maintenance, reliability, costs, and many other aspects. Paper shows possibility of application of the generalized gamma distribution family in prediction of the corrective maintenance of fleet vehicles. In this paper, the mileage expressed in kilometres is used as the lifetime of individual tram components. To illustrate the method of adaptation of operational data concerning the fleet of 45 trams, assessments of unknown parameters of the distribution of mileage to damage of a very important tram component, i.e. the drive controller, were determined. The estimation of parameters includes censored data prepared according to the developed method of processing the operational database. As the next step, on the basis of this distribution and the knowledge about the mileage of the currently used drive controllers, the conditional their unreliability were determined in the subsequent periods of using the tram fleet. The results obtained can be used by fleet operators to plan vehicle corrective maintenance.