Experimental study on the determination of traction-gripping capacity and working indicators of the forestry tractor Yanmar F535D

Abstract

The traction-gripping capacity and working indicators of a forestry agrimotor system depend on multiple factors such as machine structure, operating skills, terrain conditions, soil characteristics and the requirements of the cultivation technique. The use of mathematical equations in determination of these indicators leads to the limitations on the accuracy, variation and relationship among the indicators. The results of emperimental study has determined the important technical specifications, gripping capacity and working indicators using a moderm experimental system. On forestry terrain, the Yanmar F535D traction system equipped with improvement of the self-movement system has a rolling resistance indicator (f) of 0.081 - 0.089, representing an increase of 2.3% to 3.1% compared to the original tractor. The lateral friction indicator φ x determined at 0.695-0.752 which is represented higher than that of the original tractor with an increase of 10.93% to 13.59%. The resistance force indicator Kc is recorded at 32.620 N/m 2 at the plowing depth h c in the soil of 0.075 m. K c was determined at 37.693 N/m 2 when hc was increased to 0.1 m. The tractor system showed the stability during working at the terrain slope of 10° to 13° with the productivity of 0.33 ha/h to 0.47 ha/h. The empirical study has determined the gripping-traction characteristics of the improved self-movement tractor system on forest terrain, the relationship between traction efficiency η k and sliding index δ k, which are important parameters in assessing the technical performance of the tractor system as well as in improving the working ability of the tractor system