Value stream mapping: A case study of lock industry

Value Stream Mapping (VSM) is a useful tool to see hidden wastes and sources of these wastes in a manufacturing facility, primarily for discerning between activities that adds value to the process and activities that do not. It is one of the key lean tools used to identify opportunities for eliminating non-value adding activities, reducing production lead time and lowering work-in-process (WIP) inventory. This paper demonstrates a case study of VSM application at a special purpose lock manufacturing facility. A current state map is drawn to document how processes are operated on production floor. Through aggressive application of process improvement techniques, a future state map is developed to design a lean process flow by eliminating wasteful activities. In a major overhaul of activities, the existing process layout riddled with excessive inter-station travels was changed to an effective and cost efficient product layout. In addition, lean tools like 3G, Kaizen and 5S were implemented for better utilization of manufacturing facilities. The outcome was seen in the drastic reduction achieved in production lead time and WIP inventory. Production lead time and WIP inventory decreased by 62.74% and 66.09% respectively. Furthermore, rejection levels and unwanted travels were drastically reduced.