CV. Chikal Jaya Makmur is a make-to-order garment company that produces various clothing products such as shirts, t-shirts, jeans, sweaters, and jackets. But, the researcher only focused on production process of short-sleeves shirt. CV. CJM has a different target production each day depends on the number of employees presence. However, although the production targets are adjusted to the number of employees presence, the product realization is often did not reach the production target in several period. In the production process of shirts, researcher found inventory waste which is the buildup of work in process product in between sewing workstation that can affect the production lead time. Based on the problem of work in process that happened in several workstation of sewing process, the researcher proposed the improvement design on the production process of shirt as an effort to minimize the waste inventory to reduce the volume of work in process that accumulate in several sewing work stations.
This research phase begins from primary data collection and secondary data as a reference to map the activity mapping process to identify waste that occurs in the production process, making current state value stream mapping, identifying the cause of waste inventory by using fishbone diagram and 5 why's. After knowing the root cause of waste inventory, design of proposed improvement to reduce the cause of waste inventory need to implemented. The method to minimizing waste inventory work in process is using line balancing heuristic method: Ranked Positional Weight, Killbridge-Wester, Moodie Young Method and choose methods which produce the best result. The choosen method is Killbridge-Wester method which produce increased result of line efficiency from 42,48% in existing line to 95,2% after line balancing. And decreasing number of work in process inventory achieved was 99%.