A value stream mapping and simulation hybrid approach: application to glass industry

Abstract

This paper introduces a condensed version of lean manufacturing implementation toward improving manufacturing processes in a small to midsize glass fabrication company in Jordan. While the company suffers from long manufacturing lead times and unbalanced production line, it is almost impossible to convince the traditional administration of this small to midsize manufacturing plant to adopt the completely revolutionizing, costly, and risky (at such level) lean manufacturing approach. Therefore, a much lower cost and verified scheme of enhancement is provided. The scheme starts with value stream mapping (VSM) to visualize the process flow as well as identify production status and any potential alerts. Then, the scheme employs a discrete event simulation model to accurately estimate the impact of these potential alerts. The results of the simulation is then used to identify all the possible primary and secondary bottlenecks using multiple approaches such as utilization method, waiting time method, and scenario-based method. An improving algorithm is then utilized to systematically suggest changes aiming to relieve the system and produce a better manufacturing lead time and/or increase its throughput taking into consideration feasibility. These changes are evaluated each time using a modified simulation model. Not only did the implementation of the prescribed scheme in the glass fabrication company revealed a hidden bottleneck, but also the suggested changes reduced the manufacturing lead time by 6 % and increased the performance of the primary bottleneck by 32 %. Finally, the computerized relative allocation of facilities technique (CRAFT) was used to identify the optimal layout of the expanded system.