Abstract:
This research proposed a scheduling method for automatic wire cutting process with reducing the setup times and makespan of production. The production system in the automatic wire cutting of 20 parallel machines that the responsible for producing 140 jobs/day. Each machines setup time when changing the models in production depends on the wire cutting model that produced previously. Production scheduling in this process is a daily planning activity for generating daily production schedules that meet all demands for each day indicated in the master production plan. This research has designed production scheduling by applying 2 heuristic such as Longest processing time (LPT) and Similar required setups (MinSetup). LPT is heuristic determines which longest processing time, inputs it into machine and calculate the completion times. The completion times cannot extend past the designated critical time. MinSetup applied with LPT and need to increase the critical times 10 minutes to get the production schedules and creted a pareto diagram and choose the best production scheduling. When comparing the original method, The production scheduling from LPT, it results in a production schedule with a low makespan. But this heuristic does not take into account the machine setup times. Therefore resulting in the heuristic of having a setup machine time is relatively high. But MinSetup was found that it was able to reduce the average setup time by 77.31 minutes/day, or 10.11 % and reduce the average makespan of the system by 58.31 minutes/day or 4.71 % of the original method.