A decision methodology for maintenance interval of equipment by ordering based on element reparation-replacement rate

This paper presented a decision methodology for maintenance interval of equipment by ordering based on element reparation-replacement rate, in order to obtain optimal maintenance scheduling and reduce maintenance cost, while keeping average element reliability. Since data of failure are rare in actual equipment definitely, information from element regular maintenance based on an experience can be considered to be adapted for reflecting the feature of reliability. According to the element reparation/replace rate calculated by synthesizing multiple factors, element reliability can be quantitatively described. Through ordering element reliabilities with various average maintenance interval types, maintenance intervals of elements are rearranged meanwhile keeping average element reliability. Therefore, maintenance interval of element can be extended comparing with current maintenance scheduling, so as to reduce maintenance cost. With actual data of electrical elements in thermal power stations of Kyushu Electric Power Co. of Japan, attractive results were obtained and thus the effectiveness of the proposed strategy can be verified.