Selected physical and mechanical properties of hemp seeds

Abstract

The basic physical properties of hemp seeds were measured to determine the correlations between these properties to facilitate the planning of seed sorting operations. The basic dimensions (length, width, and thickness), terminal velocity, angle of external friction, and mass were determined in the selected seeds. The seeds were subjected to a uniaxial compressive strength test to determine the force required to damage a seed, the corresponding displacement, and the energy consumed during the trial. The seed sorting was based on the basic dimensions of the seeds in order to divide the seeds into groups with similar average mass. The hemp seeds were most effectively sorted with the use of a screen with slotted apertures. The optimal set of screens should separate approximately 11% to 24% of the seeds into a fraction with the lowest seed thickness, and approximately 16% to 21% of the seeds into a fraction with the highest seed thickness. The basic seed dimensions significantly influenced the specific mass of the individual hemp seeds, and the corresponding correlations are most effectively described by power functions.