Investigating the Effect of Stem and Blade Parameters on the Shear Strength and Specific Cutting Energy of Soybean Plant

In this research, shear strength and specific cutting energy were determined for the factors including two stem orientations (45º and 90º), four cutting heights (5, 15, 25 and 35 cm above ground level), three bevel angles (20, 30 and 40º) and three shearing velocities (5, 10 and 15 mm min-1 ). A factorial experiment was used based on randomized complete design at three replications. The results showed that shear strength decreases by increasing cutting height and increases by increasing blade bevel angle. The minimum and maximum amount of shear strength were 1.2 and 3.95 N. mm-2 at the cutting height of 35 and 5 cm and the bevel angle of 20º and 40º, respectively. Shear strength reduced by increasing shearing velocity at the both stem orientations. The minimum amount of shear strength was 1.67 N. mm-2 for the shearing velocity of 15 mm. min-1 and the stem orientation of 45º. The specific cutting energy reduced from 33.5 mJ. mm-2 at the bevel angle of 40º and the orientation angle of 90ºto 7.5 mJ. mm-2 at the bevel angle of 20º and the orientation angle of 45º. The maximum specific cutting energy was 29.7 mJ. mm-2 at the stem orientation of 90ºand the shearing velocity of 5 mm min1 . Its minimum amount was 13.24 mJ. mm-2 at the stem orientation of 45º and the shearing velocity of 15 mm.min-1 .