Lean Manufacturing for the Wood Products Industry

View our current research project here!

Lean manufacturing has become the process improvement standard for companies trying to upgrade their competitive capabilities in today’s global market. Lean manufacturing is a strategic business system, first designed and perfected by Mr. Taiichi Ohno at Toyota, which has been used with great success at world-class companies in most industries. Lean has been defined as a systematic approach to identifying and eliminating waste through continuous process improvement. Some of the basis components of lean include: just-in-time production, set-up reduction, total productive maintenance, and the “5S” system – Sort, Straighten, Scrub, Standardize, Self-discipline. The 5S system provides a foundation that allows a manufacturer to deliver high quality products in the right quantity at the right time to satisfy customer needs. Bottom line benefits for companies practicing the 5S system include reduced waste, improved safety, easier maintenance, higher product quality, and improved profitability.

The objective of lean manufacturing is to eliminate waste in all its forms, of which the primary is inventory. Through pull-type lean production techniques, called kanban systems, firms learn to produce only those components needed for the current production file. In manufacturing products that utilize homogeneous raw material (such as steel for automobiles) kanban works well; parts are machined from the raw steel stock as required, and the remaining stock awaits the next call from the system.

A number of Pennsylvania’s leading wood products manufacturers are already working to adopt lean manufacturing, or are trying to determine how lean best fits their enterprise. As they do so, they come to recognize the potential of the concept to increase their competitiveness, and to improve their bottom line. However, these same companies find that certain aspects of lean manufacturing being taught by consultants and industrial engineers will create conflicts in the recovery/inventory/cost equation of their businesses…conflicts that can be traced to the inherent variability in the raw material itself, the wood.

For instance, one of these special issues occurs in the rough mill of all secondary wood products producers. Here, the more advanced companies attempt to optimize recovery through computer-aided edging, trimming, and defecting. Since the major raw material cost of these companies is the wood itself, any successful optimization of processing that increases yield lowers raw material cost, and therefore increases the profitability of the mill.

The yield optimization procedures mentioned above typically and naturally produce by-product components that must be stored in an in-process inventory for use when called for in future production schedules. In implementing lean and attempting to reduce or eliminate their in-process inventory, wood products companies find themselves faced with the potential of discarding “good wood”. Why? Usually, because production planners apply lean by trying to machine wood to their current production schedule, rather than a yield-optimizing cutting bill. After a time, they may conclude that the decrease in yield cannot be justified by any increase in efficiency due to elimination of the in-process inventory. As a result, many companies modify their lean concept to allow for in-process inventory under certain or all conditions, or they abandon the effort completely through frustration. In at least one case, we have seen the company conclude that “just-in-time” for them meant to produce as large an inventory as possible, so as to be better able to deliver on-demand to their customer base.

As traditional lean experiences fail to resolve these and other wood-related special issues, many companies find their lean efforts stalled and employee motivation waning. Issues without answers will kill even the best of concepts. At WoodPro, we believe that these wood-related special issues can be resolved, and for that reason we are undertaking detailed research in actual facilities and under specific conditions of raw material supply, production schedule, and plant flow. Our research objectives will include developing solutions for specific combinations of wood species and grades, and how these relate to production requirements and plant layout.

If your company is undertaking a lean transformation, or is considering doing so, and you would like to explore the possibility of participating in our research, please contact us. We’d be glad to meet with you and discuss several levels of involvement.