Availability/reliability engineering analysis of three, four, and five-stage unreliable series transfer lines

Abstract

Series transfer lines provide the modern manufacturing facility with an orderly and efficient method of product assembly. Sequential tasks are assigned to specific workstations along the line. Buffers between the workstations provide on-line inventories to regulate product flow along the line. Previous reliability or availability analysis of these lines employed continuous-time Markov chain models. The analysis here focuses on recent developments in discrete-time Markov modeling of lines with unreliable workstations and nonfailing buffers. Specifically, this paper demonstrates a more stable and efficient computation of stationary-state workstation buffer model probabilities for unreliable lines. In addition, a highly efficient algorithm was developed to isolate and remove transient states from the model. Finally, a regression analysis linear model was developed to predict the effects of changing individual workstation availabilities and buffer capacities on overall line availability.