Reliability Assessment of Driving Systems of City Buses

Paper concerns reliability assessment of very sensitive subsystems from the point of view of safety of city buses analyses maladjustment of buses quality to difficult Asian operating conditions. There are discussed various factors describing operational conditions of city buses and motivation of reliability assessment of selected bus subsystems. Data base, covering times to failure of buses, was created upon real observations and enables for experimental verification of complex approach taking into account tribo-technical and statistical analysis. Failure analysis has shown weak elements in chassis and suspension. Probability failure distribution, reliability, density and hazard rate functions are assessed for leaf springs and wheel studs. Statistics is performed for mileage to first and second failure. Analysis of failure causes of some elements is shown.