Performance of a small-scale chipper for professional rural contractors

The study determined the productivity, fuel consumption and product quality obtained with a new tractor-powered drum chipper, designed to reduce the gap between industrial chippers and small-scale chippers. The machine was tested with poplar logs and beech slabs, considered as representative of the raw material commonly used for energy wood production. After accounting for accessory work and delays, productivity of green chips ranged between 4 and 6 tons per scheduled machine hour, which was very good for a tractor-powered unit. Specific fuel consumption of oven-dry chips varied between 2.5 and 3.0 L per ton, or 0.6 L per m3. These figures compared favourably with those obtained from previous studies of both smaller and bigger chippers. Chip quality was very good. Samples contained no oversize particles, qualifying for use in small-scale plants. The average size of beech chips was significantly larger than for poplar chips, possibly due to the higher strength of beech wood. © 2013 Beijing Forestry University and Springer-Verlag Berlin Heidelberg.