Research on the availability model of NC machine tool

Firstly, this paper analyzes dynamic change process for NC machine tool and gets the system state transition and its corresponding matrix of transition probabilities. The models of instantaneous availability, steady-state availability and mean availability in the setting time can be got through solving the equation of state. Then, on the base of 313 fault data from 7 NC machine tools, the solutions of three type models can be obtained. The Analysis results of the models can be applied to the establishment of maintenance strategy for NC machine tools, as well as provide basis for the availability prediction.