Maintenance strategy based on reliability functions for an oil centrifugal pump

Abstract

The purpose of this article was to define the most appropriate maintenance strategy for a centrifugal pump (preventive, predictive, corrective or emergency), based on reliability calculation. The research method was the quantitative modeling, applied in a petroleum plant. The study may contribute to the development of a strategic model for the management of the industrial plant maintenance. In the company's information system, records of eleven years have been gathered on times between failures and times for repair of the equipment. These times were modeled by probability distributions. From the results obtained were calculated Reliability and Maintainability functions R(t) and M(t). By combining their expected values (MTBF and MTTR), Av availability was calculated. The figures for MTBF, MTTR and Av were respectively 3,936 hours, 133 hours and 96.73%. The most likely shape factor of the Weibull distribution which modeled the time between failures was 0.69. So, it was possible to affirm that the pump is in the infant mortality phase. The theoretical framework of RCM indicated corrective  maintenance as the strategy for the item. This strategy aims to eliminate the defects of equipment design, reinforce items that usually break and remove the causes of the failures.