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Summary

PhD thesis presents analysis of RCM maintenance system implementation for the semi submersible rig azimuth thrusters - RCM replaced planned maintenance system. Results of RCM implementation on certain reliability indicators were analyzed. Analysis was based on empirical research. Review of publications and literaturę related to the research work revealed that there have been no research treating the problems associated with replacing planned maintenance systems with RCM and that reliability issues were omitted in the RCM implementation analysis.

It was proposed in the dissertation to carry out the analysis of RCM implementation effect on the failure distribution. Empiric azimuth thrusters failure data collected during two five years periods were used for the analysis. Times of failures of each thruster were recorded and subsequently times between failures were calculated. It was proved in the thesis that data describing failures of the individual azimuth thrusters belong to the same population and failures of all azimuth thrusters were analyzed as the same statistical sample. To analyze time between failures distribution registered when maintenance was carried out according to planned maintenance regime and after RCM implementation, distribution fitness tests were carried out. Statistical hypothesis tests were performed with Statistica 8.0 software package.

It was proved in the dissertation that RCM implementation caused the alteration of the empiric failures distribution from non-parametric to exponential distribution. It was also proved that RCM implementation caused reduction in the total number of azimuth thruster failures and the increase of median of time between failures. Characteristic of the failures altered as well. Following RCM implementation it became possible to determine dominant failures. Low effectiveness of RCM in preventing failures modeled by exponential failure distribution was proved indicating necessity to minimize such failures effects on function performed by the object.