| Abstract | This project study finds the best method for production sequencing and scheduling at Vietnam Lubricants and Chemicals Joint Stock Company (VILUBE). Finding the best solution for sequencing and scheduling problem will help to improve customer satisfaction through on-time delivery, reduce of production lead time, work in process (WIP), etc.
With the best scheduling method in place, we can easily determine the required capacity of factory and relative resources with accuracy for long time planning (e.g., next five years), and set the key performance indicators (KPIs) that are suitable and persuadable for monitoring.
With the current production processes and, the customer requirements, we apply some heuristic methods to solve the problem with following procedure: Firstly, apply the “EDD – Earliest Due Date”, or the “SPT – Shortest Processing Time”, or the “JST – Job Slack Time” rules for sequencing and scheduling the filling lines (single machine model environment). Secondly, using back-ward procedure to convert the production sequence and schedule from filling sub-process to blending sub-process (in which the filling start time will become the blending finish time). Finally, apply the LRPT – Longest Remain Processing Time rule to determine the sequence and schedule for the blending tanks (parallel machine model environment with the same speed).
The main objective is to help minimize the number of tardy jobs, minimize makespan so as to, improve the shop utilization from current value of 63.9%.
Keywords: Single machine scheduling, Parallel machine scheduling, Production sequencing and scheduling, Heuristic method. |