Feasibility and optimization of preventive maintenance in exponential machines and serial lines

This article is devoted to a theoretical study of exponential machines with maintenance-reliability coupling, according to which the machine breakdown rate is inversely proportional to the rate of Preventive Maintenance (PM). For such a machine, a feasibility condition, under which PM leads to machine efficiency improvement, is derived. Under this condition, the optimal rate of PM is calculated, and it is shown that the efficiency of the machine with exponential and deterministic PM remains practically the same. In addition, a method for production rate evaluation in serial lines with PM-optimized machines is developed, and it is illustrated that the improvement due to PM may be as high as 40%. Finally, the robustness of the obtained results with respect to the nature of PM-reliability coupling is investigated.