The effect of inequality of interstage buffer capacities and operation time variability on the efficiency of production line systems

Abstract

It has now been generally established that the output rate of balanced production lines having variable operation times can be improved by deliberately unbalancing the line through assigning proportionately lower operation times to the middle station(s). Nevertheless, a production line may be balanced in terms of mean operation times at the respective stations yet unbalanced in the sense that the interstage buffer capacity allocation or the operation time variability are not equal for all stations. This paper attempts to study the effect that the latter types of imbalance have on the output rate and average number of work units in the system for some production line situations. Computer simulation experimentation results confirm that inequality of variability of operation times have the same general effect on output rate as inequality of operation times but little effect on the number of units in the system. Inequality of interstage buffers, on the other hand, affects the average number of units in the system but has little effect on the output rate.