Computer simulation was used to evaluate the performance of three scenarios of sawmill operation: 1) External Scanning at the bucking station, 2) X-ray Scanning with external plus partial internal knot scanning at the bucking station and 3) Perfect Scanning with external plus full internal knot scanning throughout the mill.
Forty sample stems were scanned and stem models developed to provide input for Forintek’s sawing simulation program, OPTITEK®. Input files of both sawmill machinery and their products were developed based upon the operation of a typical sawmill in the Interior of B.C. Optimized bucking solutions were generated, and sample stems were sawn accordingly. Lumber value and volume recovery data were obtained and enabled a comparison of the performance of the three operational scenarios.
The X-ray Scanner Scenario provided a 2% value recovery increase compared to that of External Scanner Scenario. The Perfect Scanner Scenario added an additional 5.5% to that of X-ray Scanner Scenario. This was due partly to improved scanning at the bucking station but more so to the internal defect detection at all machine centers in the mill.
Conclusions of the study should help sawmillers in their investment decisions regarding sawing optimization improvements.