IMPROVING SCHEDULING OF PLASTIC TRAY PRODUCTION USING CAMPBELL, DUDEK, AND SMITH (CDS) AND NAWAZ, ENSCORE AND HAM (NEH) ALGORITHM AT PLASTIC MANUFACTURING

Abstract

In production operations, scheduling is needed to optimize several jobs in sequence machines. The scheduling method used in plastic manufacturing is EDD (Earliest Due Date) that cause the company's target of daily production and scheduling was not achieved. This research objective is to improve in the production scheduling methods to minimize makespan in order to achieve production targets. Algorithm of NEH (Nawaz, Enscore, and Ham) and CDS (Campbell, Dudek, and Smith) for jobs with different arrival time is implemented to find optimal solutions in production scheduling. The comparison results with the EDD method, the NEH algorithm can reduce makespan from 34 days to 8 days, which reduces about 76.47%. Meanwhile, the CDS algorithm can reduce makespan by 11.76%, from 34 days to 30 days. The CDS algorithm considering the arrival time of each job so, this method is used to improve production scheduling at PT. FDN. In addition, changing the cutting process to using a trim machine can reduce cycle time by 61.11% from 28.8 seconds/unit to 11.12 seconds/unit.