Optimization of the Maintenance Program of Elevating Equipment Using Risk Assessment

Abstract

Maintenance program for elevating equipments is basically done in time-based concept. Inspection periods are determined for each item which is composed of plural parts; however, this inspection interval is based on experiences and does not have clear scientific backgrounds. In order to rationalize the maintenance program, the application of available data such as failure reports given by customers, and inspection data reported at periodical maintenance is extremely important. Unfortunately, this information is not necessarily utilized sufficiently at this moment. In this research, we try to quantify a risk by calculating failure rates and harm severities of each maintenance item. When calculating the failure rate, we use a statistical method and take “interruption data” into consideration to make up for the lack of data. When defining the harm severities, we evaluate the suspension time caused by the failure of . Finally, by multiplying the failure rate and the harm severity, we quantify a risk which matches maintenance executer's sense, and develop the method of optimizing the maintenance program based on risk.