Input scheduling and load balance control for a job shop

This paper deals with a method for scheduling and control of a maching job shop where the average number of operation stages per part is six and the average operation time per stage is about one hour. The method is based on the adjustment of load balance among machines and the limitation of the amount of work input. By simulation with real data, it was found that two variables, the load balance and input amount of work, definitely influence shop performances such as lateness, mean flow time and utilization of machines. If these two variables are well controlled, good results can be obtained no matter what the dispatching priority rules on the shop floor may be.