Pull Manufacturing System Design for Rough Mill Systems: A Case Study

Abstract

Domestic secondary wood products manufacturers are losing their competitive edge in the global economy. Foreign competition is steadily gaining market-share due to decreased labor costs. While domestic operations can not compete with labor costs available to foreign manufacturers, they may be able to remain competitive through product lead time reduction and on-time delivery to the final customer. Pull based manufacturing is one technique to reduce lead time increase on-time delivery.

Value stream mapping was used in this project to evaluate a furniture rough mill located in Virginia to assess the current state, as well as develop 2 future state value streams. The current state evaluation found the system to be yield driven and production was based on a forecast. The lead time for internal nightstand components in the current state was found to be 15.1 hours. Using pull production and supermarket methodology in proposed future states, it was found that the lead time could be reduced to 7.5 hours. Lead times could be reduced by eliminating yield increasing non-value added activities currently in place which not only increase lead time, but also manufacturing waste as defined by lean manufacturing concepts. A cost analysis found that the labor and overhead costs associated with yield increasing activities in the current state outweighed the costs of a decreased yield measurement in the future state.

While this project was limited to one rough mill and one product family of a lesser valued wood species it represents what is possible for assisting secondary manufacturers to remain competitive. The once successful traditional yield driven rough mill does not guarantee internal customer satisfaction and in this project is not cost effective. Future research should focus on the implications of the furniture rough mill's inability to meet downstream demand to internal customers.