Determination of some mechanical properties of parsley stems related to design of processing machines

To develop a cutting, harvesting, crushing or grinding machine, knowledge of crop physical and mechanical properties is needed. In this study, shear strength, shear energy and maximum shear force in cutting parsley stems have been examined. Cutting of multiple stems (8 stems) was performed by using blades with oblique angles of 0, 20, and 40 degrees. In order to examine the effect of stem arrangement in cutting operation, stems were placed in row and bundle arrangements. Statistical analysis showed that shear strength and maximum shear force decreased with increasing oblique angle. The average values of shear strength, specific cutting energy and maximum shear force for cutting 8 stems laid in row arrangement, using blade oblique angle of zero degrees, were 0.49 MPa, 2.25 mJ mm^-2 and 56.13 N, respectively, while at blade angle of 40 degrees the values were 0.19 MPa, 4.12 mJ mm^-2 and 18.2 N, respectively. Blade angle of 20 degrees is recommended as it does not require more cutting energy compared to zero degree and the shear force is reduced, which lessens the effect of impacts on the cutting system.