Resumo

NAJERA-LUNA, Juan Abel et al. Lumber yield and production time in the El Salto region of Durango, México. Rev. Chapingo [online]. 2011, vol.17, n.2, pp. 199-213. ISSN 0186-3231.  http://dx.doi.org/10.5154/r.rchscfa.2010.05.034.

To determine log characteristics that affect lumber yield and production time, a study was conducted of productivity indicators at five sawmills in the El Salto region of Durango, Mexico. Logs of five diameter classes, three lengths and six taper classes were analyzed. To estimate log-sawing times, the "back to zero" methodology was used; for determining lumber yield, volume in cubic meters inside and outside of bark of 412 pine logs was calculated and compared with the resulting volume in lumber products. Total inside- and outside-bark volumes were 293.73 and 323.93 m³ of roundwood, respectively, which yielded 7,085 board feet and 169.01 m³ of sawed wood, which represents a 57.5 % and 52.17 % conversion of inside-bark and outside-bark volumes, respectively, to sawn boards. The average time for sawing 1,000 board feet was estimated at 25.09 minutes for a production of 7.57 m³h^-1, with an average carriage feed rate of 46.47 m·min^-1. Our findings indicate that lumber recovery is affected by log diameter, length and taper.

Palavras-chave : Ergonomics; lumber; logs; sawmills.