In the research, we compared two technological systems of timber extraction: extraction with a tractor with a forestry winch and extraction with a forestry trailer with preskidding carried out with a forestry winch. The research took place in the GGN Ruše, and it included a time study, distance measurements, load volume, fuel consumption, and cost calculations. Extraction with the winch comprised 8 cycles with an average load volume of 2.82 m³ per cycle and an efficiency of 12,20 min/m³ at an average extraction distance of 440.15 m. Extraction with the trailer comprised 10 cycles with an average load volume of 4.75 m³ per cycle and an efficiency of 8,42 min/m³ at an average extraction distance of 579.75 m. Fuel consumption in extraction with the winch amounted to 0.91 l/m³, with the trailer 0.53 l/m³, and the cost per working hour was 36.78 EUR/h and 43.79 EUR/h, respectively. The comparison of efficiency between the two working systems showed that, with regard to efficiency, extraction with a forestry
winch is reasonable to use up to an extraction distance of 480 m, and with regard to costs, up to 360 m. On the basis of the research, we can conclude that timber extraction with a trailer without pre-skidding is possible only in the case that the tractor with the trailer also moves outside the skid trails. In this case, the output per production unit is higher and the costs are lower than in extraction with the winch. With pre-skidding included, timber extraction with a tractor with a trailer is reasonable to use at extraction distances longer than 350 m.
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