Temporal Analysis of Material Retention and Loss at Final Inspection Stage in Plywood Manufacturing

Abstract

Despite extensive studies on product quality and process optimization in plywood manufacturing, limited attention has been given to interpreting routine inspection data as indicators of temporal material retention efficiency. Efficient utilization of forest resources is not only determined by harvesting practices but also by the ability of downstream industries to retain wood material within productive manufacturing flows. In plywood manufacturing, the proportion of material classified as acceptable product represents the primary yield of forest-derived raw material. This study analyzes the temporal dynamics of primary yield in plywood manufacturing using monthly production inspection data. A quantitative descriptive approach was applied to data collected over a four-month period, where overlap-related (OVL) products were classified as acceptable output, while under-thickness deviations (UTY) were treated as material loss. The results show that overlap-related products accounted for more than 94% of the total inspected volume, indicating a consistently high primary yield. Minor fluctuations in yield across months suggest temporal variability in material retention efficiency. The findings demonstrate that high primary yield contributes positively to forest resource utilization efficiency by reducing the need for additional raw wood input and supporting sustainable forest resource management.