Increasing wood fuel processing efficiency by fine-tuning chipper settings

Latest chipper models feature new in-feed and evacuation systems that can be adjusted on the fly to match variable work conditions. Proper adjustments of the two systems are expected to produce significant effects in terms of productivity, diesel fuel consumption and chip quality. The study verified such claims by testing one of these new machines in a controlled experiment, conducted under two alternative in-feed and evacuation system settings on two different feedstock types (2 × 2 × 2 = 8 treatment combinations). Each treatment was repeated 5 to 10 times, depending on feedstock availability. The study showed that feedstock type has a dominant effect on all the studied parameters, whereas in-feed mode has no effect on any of them. In contrast, blower setting has a significant effect and offers a strong potential for increased wood fuel processing efficiency. In particular, decreasing blower speed when full ejection power is not necessary allows reducing diesel fuel consumption between 6 and 16%, while increasing chip integrity by 20%.