Evaluation of some effective parameters on energy consumption in drum chipper

Chips producing and wood chipping are very basic and important step in wood chipboard factories that are determinant in final products quality and price. Producing high quality chips with effective dimension and size, not only guaranties high quality in final product, but also reduce stay time in secondary machines and subsequently and energy consumption. The aim of this study was evaluation of effective parameters on energy consumption in drum chipper which was done in Rosenheim University of applied sciences (Germany). For this reason, the impact of wood species, cutting velocity, moisture and wood dimension was evaluated. For precise investigation of energy consumption in any situation of experimental design equal weight of the trunk converted to chips. Also, chips thickness in all the exams imagines stable.

In this study Poplus termula and Quercus Robur was used. First, samples through band saw blade ESTERER Model EB 1400 converted to lumbers with dimension 4×8 cm and 8×8 cm. Then samples dried in chamber LAUBER TROCKNUNGSTECHNIK with automatic system to reach 18 and 40 percent moisture content. Next samples based on experimental design which was prepared with factorial design and equal weight of the trunk feed to drum chipper. Cutting velocity through the speed of rotation of engine in 3 level, 16, 20 and 24 meters per second was managed. The energy consumption during the process by Multi-channel precision power meter measured.

After analyzing data results showed that, influence of species, moisture and cutting velocity had significant effect in 95 percent confidence level. Main effect plot showed that, Oak species compared to poplar 40 percent moisture compared to 18 percent, 20 m/s cutting velocity in comparison with 24 and 16 has lesser energy consumption. Also result showed that, cutting velocity had most main effect and moisture had least main effect on energy consumption in 95 percent confidence level. The result of analysis of variances showed that the effect of thickness on energy consumption is not significant.

The results of reactions showed that while thickness did not have significant effect on energy consumption but compared to other variables it had the most effect. with evaluation result, observed that Oak with 40 percent moisture, 4 cm thickness and 20 m/s cutting velocity had least energy consumption, while poplar with 18 percent moisture, 8 cm thickness and 20 m/s had least energy consumption. This differences in energy consumption can happen because of difference in texture of 2 species. This can stem from different characteristic and elastic properties of the studied species as in poplar with increasing moisture content and thickness, wood deformation against cutting force increased and finally led to increasing energy consumption.