Availability calculating of open pit mine loading system based on Markov chain model

Availability is one of the most important characteristics of the repairable machines system performance and improvement of production planning. Loading operation in an important part of the mine production cycle and in this paper an approach to calculate availability of open pit mine loading system based on Markov chain theory has proposed. Markov method is based on the different modes of the system and the transition from a state to another state, therefor data analysis and failure and repair rate determination are important. To illustrate the application of model, the Mishdowan iron mine data was used. For this purpose beside the calculation of failure and repair rate indexes, availability of loading system has been determined using a Markov chain model and related statistical tests was used to detecting the failure and repair behavior of system in the high degree of accuracy. Based on the results obtained, failure and repair rate for Newholland hydraulic excavator are 0.019 and 0.064 and for Komatsu hydraulic excavator are 0.017 and 0.047, respectively. Additionally, availability of hydraulic excavators of mine loading system is evaluated to be 93.3 percent.