Abstract: For the equipment deterioration condition can not be diagnosed directly in indirect monitoring, this paper proposed a method of equipment preventive maintenance strategy with minimum cost. By using Markov chain to express equipment deterioration condition, the equipment reliability function was proposed. Bayes rule and the hidden Markov model were used to research equipment condition probability distribution . The equipment maintenance cost model and the equipment residual life model were established in indirect monitoring to carry equipment maintenance strategy analysis based on maintenance cost and residual life. The implementation of the optimum maintenance decision criterion was illustrated based on maintenance cost and residual life in indirect monitoring.
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Key words: condition-based maintenance, indirect monitoring, equipment residual life, Markov processes, equipment maintenance strategy