ESTIMATION OF PRODUCTIVITY AND PRIME COST OF LOGSET 5HP GT HARVESTER IN THINNING

Abstract

Productivity of a harvester significantly affects costs of mechanized felling, which in turn determines, if commercial thinning will be profitable. The objective of this study is to estimate productivity and prime cost of Logset 5HP GT harvester with increased boom length (11 m), equipped with the TH45 felling head, in thinning. Trials are conducted in Latvia, eastern Vidzeme, in coniferous stands. To evaluate productivity of Logset 5HP GT, a time study was carried out. Influence of small trees (diameter at breast height < 8 cm) on productivity and harvesting cost was also determined. During the trials 2379 trees are harvested with the total stem volume of 400 m³. The diameter at breast height of an average harvested tree is 14 cm and volume of a stem – 0.171 m³. Duration of time study is 33.5 h. Obtained productivity rates of Logset 5HP GT are compared with those of John Deere 1070 D harvester. According to the study results average productivity of Logset 5HP GT harvester in thinning of coniferous stands is 13.85 m³ per productive work hour. Prime cost of harvesting of the Logset 5HP GT in thinning is 8.02 € m^-3. Increased boom length allows to decrease the total time spent for driving in a stand by 71%. Harvesting of small trees reduces productivity by 6.9% and increase production cost by 2.1% in the experimental stands. Difference between productivity of Logset 5HP GT and John Deere 1070 D in similar conditions is statistically insignificant.

Keywords: harvester, harvesting productivity, Logset 5HP GT, thinning

Article DOI: http://doi.org/10.15544/RD.2017.175