COMPARISON OF PRODUCTIVITY OF KRANMAN BISON 10000 FORWARDER IN STANDS HARVESTED WITH HARVESTER AND CHAINSAW.

The aim of this study is to investigate potential uses of Kranman Bison 10000 6WD forwarder in stands, where roundwood is extracted with a chainsaw and Vimek 404 T5 harvester in normal and difficult forwarding conditions. Productivity of Kranman forwarder was compared with medium-sized John Deere 810 forwarder under normal conditions. In total 230 loads were forwarded during the study, including 63 loads from areas, harvested with a chainsaw, and 167 loads from areas, harvested with Vimek 404 harvester. The average forwarded load is 2.0 m3 (the maximum load is 2.5 m3 therefore the average load capacity is 80%). In average 33 minutes of productive work time were spent by forwarding one load (the proportion of productive working time is 94% from total engine hours of the machine). The average length of forwarding road in trials is 286 m. In normal conditions forwarding of 1 m3 of roundwood extracted with a chainsaw takes 15 minutes of productive working time, but in difficult forwarding conditions the time consumption increases by 13%. The average forwarder fuel consumption is 1.8 L per hour. Accordingly, 0.8 L of fuel are consumed to forward 1 m3 roundwood. In comparison, John Deere 810 under similar conditions consumed 1.6 L fuel to forward 1 m3 roundwood. Study results prove that the best application of Kranman Bison 10000 is forwarding small stands or individual trees logged with a chainsaw. Forwarder can work on soils with low bearing capacity, however productivity can be significantly reduced by stumps and uneven terrain. [ABSTRACT FROM AUTHOR]