Method for reliability improvement
There is a “why why analysis” to be used for tracking real cause of facility troubles.
This analysis is an application of ” five why” method used by Toyota to facility trouble
Another method is the P (physical) M (mechanism)analysis to be used for the chronic
trouble analysis. This method focuses on the microscopic aspects of physical and mechanical behavior such as friction resistance. viscosity and strength. This is used by specialized maintenance field of PM promotion activity.
As the reliability analysis method FMEA is used in design stage to extract weak points of facility systematically and take measures to prevent them But it is difficult to express interaction of causes.
FTA (Fault Tree Analysis)used to analyze causes of failures using AND gates and OR
gates in the form of tree together with probability of these.
Weibull analysis can be used to judge whether facility are in the sporadic failure stage or wear failure stage by the trend of analysis chart.It can be used when similar multiple facilities are used. This method can contribute information as to which measure to take and how much to spend for maintenance.