Conversion factor of forest products in sawmilling of pallets in Durango, Mexico

Abstract

Reducing the loss of raw material and improving production are tasks in continuous development in the productive sector. The aim of this study was to determine the conversion factor of raw material into pallets for packaging products. The sawing process was evaluated in four sawmills in El Salto, Durango, Mexico, selecting 308 pine logs with diameters of 14 to 41 cm and 1.07 m in length, divided into four diameter categories. Sawmilling time was obtained by timing the process with a precision of 1/100 second; the volume of logs and the products generated were measured by xylometer; performance was estimated by the proportion of lumber between the volume round wood and production costs, given by the sum of the fixed and variable costs of the process. Results showed that for every cubic meter of round wood that is sawn, it is possible to obtain 217 board feet (bf) in pallet parts and 207 bf of waste. The time needed to saw 1.00 m3 of logs was estimated at 1.95 hours, thus the productivity was 0.513 m3 r h-1. The conversion factor indicated that for 1.00 m3 of pieces for pallets is required 1.95 m3 r h-1 of round wood. The production cost was US $ 161.30 per sawn cubic meter. As the diameter of the logs increases, also does performance and productivity, while the processing time and production costs diminish.