Abstract
Using re-entrant production line as the target of study, this research developed a set of production loss calculation formulae upon which an equipment capacity loss management system is established.The functions of the system include:1. Providing a decision-making process for managers to use so that a better preventive maintenance strategy can be used and the impact on capacity loss can be minimized.2. Providing a means to estimate the overall capacity loss on a given production line when an unscheduled machine down occurs. The impacts and the determining factors for various unscheduled capacity losses can be calculated so that maintenance and repain priorities can be made more effectively.eM-Plant4.6 was used as simulation tool to verify the validity of the capacity loss formulae. The capacity loss management system thus developed for re-entrant lines can also be used for straight line production by setting the flow rate for the returning routes to zero.