Failure cause identification of tribo-mechanical systems using fault tree—a digraph approach

A procedure for the failure cause identification of tribo-mechanical systems is presented based on fault-tree using a digraph approach. A variable-event system digraph for a tribo-mechanical system is suggested which takes into account structure of the system. A top event or undesirable event for the system is then defined and the fault-tree for this top event is deduced from the digraph by back-tracking it. The analysis of the fault-tree aids the design and practising engineers in design and development of reliable, safe and productive tribo-mechanical systems. The methodology is applied to journal bearing oil supply system in a power plant application.