Producing chopped firewood with firewood processors

Abstract The TTS Institute's research and development project studied both the productivity of new, chopped firewood processors (cross-cutting and splitting machines) suitable for professional and independent small-scale production, and the costs of the chopped firewood produced. Seven chopped firewood processors were tested in the research, six of which were sawing processors and one shearing processor. The chopping work was carried out using wood feeding racks and a wood lifter. The work was also carried out without any feeding appliances. Altogether 132.5 solid m 3 of wood were chopped in the time studies. The firewood processor used had the most significant impact on chopping work productivity. In addition to the firewood processor, the stem mid-diameter, the length of the raw material, and of the firewood were also found to affect productivity. The wood feeding systems also affected productivity. If there is a feeding rack and hydraulic grapple loader available for use in chopping firewood, then it is worth using the wood feeding rack. A wood lifter is only worth using with the largest stems (over 20 cm mid-diameter) if a feeding rack cannot be used. When producing chopped firewood from small-diameter wood, i.e. with a mid-diameter less than 10 cm, the costs of chopping work were over 10 € solid m −3 with sawing firewood processors. The shearing firewood processor with a guillotine blade achieved a cost level of 5 € solid m −3 when the mid-diameter of the chopped stem was 10 cm. In addition to the raw material, the cost-efficient chopping work also requires several hundred annual operating hours with a firewood processor, which is difficult for individual firewood entrepreneurs to achieve. The operating hours of firewood processors can be increased to the required level by the joint use of the processors by a number of firewood entrepreneurs.