Since the cost of fuel is an important consideration in using off-road equipment, it is to the advantage of all machine owners to get the best out of this inevitable expense. Some work habits and operational factors have an impact on fuel consumption. Recent tests conducted by FPInnovations’ researchers have made it possible to explore certain potential improvements in energy intensity (litres of fuel burned to produce one cubic metre of wood) and measure the savings.
The feller-buncher is a complex machine, due to the many hydraulic systems. Maintenance, which may seem optional when the machine is always in operation, may be difficult to contemplate. However, hydraulic tune-up tests have helped increase productivity and reduce energy intensity from 0.54 L/m3 to 0.43 L/m3, which corresponds to an improvement of approximately 20%. The return on investment in carrying out maintenance has been evaluated at less than 200 hours (Info Note 2017, no. 16).
Sharpening saw teeth can reduce fuel consumption and boost productivity by increasing energy intensity by 13%. A daily inspection of the saw teeth is therefore recommended to check whether they are still very sharp and safe (Info Note 2017, no. 10).
A change in engine operating speed may have a negative impact on fuel consumption. A 100 rpm engine speed drop test reduced productivity and increased fuel consumption and energy intensity by 6.5%. This practice is therefore not recommended on this type of machine; however, other machines may react differently (Info Note 2017, no. 17).
Excavators and machines mounted on a similar chassis are often equipped with an economy mode on the throttle lever. Tests have shown that this mode, when used in the right conditions, can reduce fuel consumption by 20%, while having a negligible effect on productivity (Info Note 2017, no. 11).
It is preferable to change the chain on the head of a danglehead processor as soon as it shows signs of losing its sharpness. A used chain reduces productivity and increases operating costs. It has been shown that using a well-sharpened new chain may reduce energy intensity by 15% (Info Note 2017, no. 12).
Tests performed with a swing machine with three different power level settings (economy, power, and high performance) and equipped with a danglehead processor showed a linear increase in both productivity and energy intensity. The high performance setting had 15% more production than the economy mode but consumed more fuel, with a 12% increase in energy intensity. Power mode struck a balance between productivity and economy (Info Note 2018, no. 2).
The position of a skidder’s grapple can have a large impact on the resistance force of the trunks on the ground and therefore on fuel consumption as well. Pulling the trunks from a high position reduces their resistance, resulting in lower fuel consumption. A difference of 25% in consumption was noted between the high and low position on a favourable slope. Tests on a 5% gradient showed that the grapple position had less impact on consumption (a difference of 3% between the high and low position). Skidding on an unfavourable slope can increase fuel consumption and unit operating costs (Info Note 2017, no. 7).
For more information, contact Cameron Rittich, Senior Scientist in FPInnovations’ Transport & Energy group.
FPInnovations members can also find more information by consulting the various Info Note reports indicated in this text.