Rough Mill Simulations Reveal That Productivity When Processing Short Lumber Can Be High

Abstract

Handling rates and costs associated with using short-length lumber (less than 8 ft. long) in furniture and cabinet industry rough mills have been assumed to be prohibitive. Discrete-event systems simulation models of both a crosscut-first and gang-rip-first rough mill were built to measure the effect of lumber length on equipment utilization and the volume and value of the rough parts produced. In the crosscut-first mill model, the volume and value of parts produced from short-length lumber compared favorably with the volume and value of parts produced from the medium- (8 to 13 ft. long) and long- (14 to 16 ft. long) length lumber. A ãconservative caseä short-lumber scenario was also simulated in which the distribution of cutting lengths was varied. The short-lumber volume and value yields for this model version were somewhat lower than the medium- and long-lumber yields. In the gang-rip-first mill model, the volume and value of parts produced from short lumber were equal to approximately 60 percent of the production from the medium and long lumber. The unstacker and planer were unable to provide sufficient material to the ripsaws which, in turn, were unable to process the short lumber fast enough to keep the chop saws busy.

Citation

Wiedenbeck, Janice K.; Araman, Philip A. 1995. Rough Mill Simulations Reveal That Productivity When Processing Short Lumber Can Be High. Forest Products Journal. 45(1): 40-46.