AbstractThe performance of an assembly line can be improved by deliberately unbalancing it under certain conditions. Two types of unbalanced lines, bowl versus inverted bowl line arrangements, have been assessed in previous studies, which assumed either no buffer stocks or infinite buffer stocb between any pair of work stations. Obviously, these assumptions are unrealistic. In this paper the buffer effects on the perfonnanae of bowl versus inverted bowl line arrangements are evaluated through a new simulation model Cor a hypothetical assembly line with a certain buffer capacity. The results of the simulation show that buffer capacity has significant influence on the performance oC both bowl and inverted bowl assembly lines in tenns of the total elapsed time to complete certain productions. It is found that bowl is superior to inverted bowl only when 10 or fewer buffer stocles are allowed, whereas inverted bowl is superior to bowl in cases where more buffer stocks are applied.