Reliability Study Of Automobile Brake System And Determine It , S Critical Components

Brake system reliability which affects running security directly is the main reason of mechanical failure caused accidents. It's of great significance to do overall reliability analysis of the brake system from the point of critical components, for the brake system's structure and theory is complex, to determine the critical components in major impact on driving safety, such as high accident rate, large severity, difficult maintenance, then we can focus the energy on the important place.On the foundation of function, structure, and principle of automobile brake system, this paper advance a new definition of brake system critical components. Respectively analysis hydraulic and baric brake system's failure modes and effects. As truck's driving feature is large load, fast speed and most for long-distance transport, the road conditions and climatic conditions are changing, it has higher risk on driving safety. This article highlights on the dual baric circuit braking system of one kind of truck, builds fault tree of it's function failure, then gets the basic components important degree of probability by computer aided fault tree analysis (CAFTA). Then analysis risks by failure mode's effect severity ranking, occurrence probability ranking and detection difficulty ranking to determine the risk coefficient, critical degree is calculated and critical components is determined.To improve the reliability of the brake system, first we must comprehend the reliability's status quo level. The function of brake system failure modes was processed by computer. So the time-varying reliability of braking system can be calculated in reliability diagram. We can see reliability curve decreased rapidly with time rising, the reliability is only 0.54 at 10000km.Then failure curve of every basic failure mode is drawn in MATLAB, critical components failure was analyzed, schemes on maintenance or improved design was proposed.