The performance of unpaced production lines with unbalanced mean operation times and unreliability patterns

This paper reports on the performance of unbalanced non-automated production lines, whose workstations differ in terms of their mean operation times and their degree of unreliability (failure and repair rates). Simulations are done of 5- and 8-station lines with 1, 2 and 6 buffer units. Statistical analysis shows that breakdown patterns have a significant effect in terms of throughput and average buffer level, leading to the conclusion that the study of unreliable unbalanced lines needs not only take into account overall line breakdown, but should consider where in the line failure occurs.