Determinación del coeficiente y calidad de aserrío del género Pinus en la región Sierra Sur, Oaxaca, México

Abstract

Se estudiaron las operaciones de un aserradero para conocer el coeficiente de aprovechamiento y la calidad dimensional de la madera aserrada en un aserradero ubicado en Sierra Sur de Oaxaca, México. Para determinar el coeficiente de aprovechamiento se cubicaron 101 trozas de clases diamétricas variadas con longitud de 2.63 m, obteniendo un volumen de 63.37 y 58.35 m3, con corteza y sin corteza respectivamente. Para determinar el rendimiento en madera aserrada, se agruparon las trozas en ocho categorías diamétricas y siete de conicidad. El estudio de tiempos y movimientos comprendió en análisis de observaciones por muestreo en intervalos de dos minutos para las tres secciones principales del aserradero (Sierra principal, canteadora y despuntadora). Se obtuvieron un total de 1875 tablas de 19.05 mm de espesor en clase tercera y cuarta, lo que representa 30.12 m3 de madera aserrada. El coeficiente de aprovechamiento promedio fue de 44.18% con corteza y 48.27% sin corteza, indicando que de 1 m3r sin corteza procesado se obtienen 216 pt de madera aserrada y para obtener 1000 pt se requieren 4.62 m3 de madera en rollo. El estudio de tiempos y movimientos mostró que la sierra principal obtiene un tiempo de trabajo del 70.63%, la canteadora el 54.21% y la despuntadora el 26.02%.

A sawmill operations were studied to know the coefficient of utilization and the dimensional quality of the timber located in the Sierra Sur of Oaxaca, Mexico. This was done during the transformation of pieces of wood in the Pinus spp. at the facilities of the Specialized Unit of Communal Forest Resources, located in the village of Santa Cruz Itundujia. A total of 101 pieces of wood were analyzed using the Samalian formula; the pieces had varied diametric measures, length of 2.63m, and a volume of 63.37 and 58.35 m3 , with and without bark. To determine the efficiency of sawed wood, the pieces of wood were classified in groups of eight diametric categories and seven of conical shape. The study of time and movement included analysis of observations per sampling in intervals of two minutes to the three principal sections of the sawmill (saw, edge banding machine, and circular saw). When the pieces of wood were processed, 1875 planks were generated with a 19.05 mm of thickness; the production was evaluated in third and fourth class which was located with the decimal metric system, symbolizing 30.12 m3 of sawed wood. The coefficient of progress rate was 44.18% with and without bark, indicating that from every 1 m3 r without bark, 216 of sawed wood is processed and to obtain 1000 pt, 4.62 meters m3 r of woodrollsare is required. The study of time and movements showed that the main saw obtains a work time of 70.63%, the edge-banding machine 54.21%, and the circular saw 26.02%.