Avaliação do desdobro de toras de Eucalyptus para a obtenção de peças estruturais

Abstract

The control over the products of the sawing of logs is important for the management of the sawmill and also to reduce environmental impacts. The yield and the time study are parameters for the assessment of unfolding in a sawmill. This study aimed to evaluate the yield and the time study of the sawing of Eucalyptus logs during the production of structural parts. This work used ten logs of Eucalyptus grandis from a plantation with 15 years of age, taken from an area of the Federal University of Lavras (UFLA). In the experimental sawmill of UFLA the logs were sawn using a band saw and the planks were resawn in a circular saw. The structural parts followed the dimensions laid down in the NBR 7190 (ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS - ABNT, 1997). The parts produced were measured and calculated yield. The times of all stages of the process were obtained using a stopwatch and then analyzed the time actually sawing and the processing time of logs and planks. The average of yield for the production of main parts was 20.9% and secondary part was 22.9%. Average yield of sawing was satisfactory if compared with the values obtained in other studies. The circular saw compared to band saw showed higher percentage of effective time sawing of wood. The effective time of sawing was less than half the total processing time of the logs.