Australian researchers have provided new information on Eucalyptus logging./Infield chipping Precision Husky blue gum.JPG)
The system studied consisted of a tracked feller-buncher, two grapple skidders, a chain flail debarker and a mobile chipper. The processing machines were located on a roadside landing. The system was producing pulpwood quality chips from Eucalyptus globulus (blue gum). The researchers were trying to determine machine productivity, operational costs, fuel consumption, chip quality and the amount of residues retained in the field after harvesting. The average tree size being harvested was 0.21 m3, the trial area had a stand density of 711 stems per hectare and the terrain was flat. The trucks transporting the chips had a 60 tonne loading capacity and travelled 58 km to the offloading point. Average skidder extraction distances varied between 190 and 256 m. The table below shows some of the key results.
The system studied consisted of a tracked feller-buncher, two grapple skidders, a chain flail debarker and a mobile chipper. The processing machines were located on a roadside landing. The system was producing pulpwood quality chips from Eucalyptus globulus (blue gum). The researchers were trying to determine machine productivity, operational costs, fuel consumption, chip quality and the amount of residues retained in the field after harvesting. The average tree size being harvested was 0.21 m3, the trial area had a stand density of 711 stems per hectare and the terrain was flat. The trucks transporting the chips had a 60 tonne loading capacity and travelled 58 km to the offloading point. Average skidder extraction distances varied between 190 and 256 m. The table below shows some of the key results.
| Machine type | Productivity (Tonnes / machine hour) | Cost ($ / tonne) | Fuel (l / hr) | Fuel (l / tonne) |
| Feller-buncher | 97.26 | 2.55 | 32.09 | 0.33 |
| Grapple skidders (2) | 60.22 | 12.02 | 91.91 | 1.58 |
| Flail debarker | 57.80 | 5.98 | 44.51 | 0.77 |
| Chipper | 58.18 | 6.59 | 72.14 | 1.24 |
| Chip truck | 14.96 | 4.19 | - | - |
| Total | - | 31.33 | - | 3.92 |
The skidders spent 49% of their time clearing residues and achieved lower productivity than other similar studies, which contributed significantly to their costs. The bark content of the chips was 0.18%, well within the limits of the specific company’s specifications (less than 0.5%). The residues returned to the site were low, being 6.4 tonnes per hectare.
The research was published in the Croatian Journal of Forest Engineering, Vol. 34(2) of 2013. The authors were M Ghaffariyan, M Brown and R Spinelli. Source: http://www.crojfe.com/articles-754
The research was published in the Croatian Journal of Forest Engineering, Vol. 34(2) of 2013. The authors were M Ghaffariyan, M Brown and R Spinelli. Source: http://www.crojfe.com/articles-754