Determination of some physical and mechanical properties of soybean and maize in relation to planter design

Abstract

Maize and soybeans are agricultural materials that serve as food to both man and livestock and also serve as by-product used in manufacturing industries. The knowledge of some physical and mechanical properties of these seeds is important tool for designing agricultural machines and equipment for planting, harvesting, processing, packaging and storage. Some of the properties determined include size, geometric mean diameter, surface area, bulk volume, bulk density, true density, porosity, sphericity, angle of repose, coefficient of friction, rupture force and rupture energy. The mean values measured and recorded for the length, width, thickness, geometric mean diameter, surface area, bulk volume, bulk density, true density, porosity and sphericity of maize and soybean were 1.043 cm, 0.883 cm, 0.405 cm, 0.716 cm, 1.621cm², 29.200 ml, 1.169 g/ml, 1.369 g/ml, 14.599% and 0.693; 0.737 cm, 0.627 cm, 0.468 cm, 0.600 cm, 1.135 cm², 16.6 ml, 1.071 g/ml, 1.0865 g/ml, 1.397% and 0.814 respectively. The mean angle of repose and coefficient of friction over stainless steel, galvanized steel, mild steel and plywood for maize and soybean were 38.6° and 0.805, 36.7° and 0.746, 38.28° and 0.794 and 34.75° and 0.702; 53.91° and 1.407, 51.67° and 1.293, 48.33° and 1.1425 and 47.67° and 1.110 respectively. The rupture forces on the major, intermediate and minor axis for maize and soybean were measured and recorded to be 175.296 N,156.550 N and 328.488 N; 52.562 N, 40.504N and 0 N respectively. The properties determined relevant to the design of the components of a planter such as the hopper, the seed plate and the delivery tube. It also helps in the selection of materials to use and to know the amount of force a material can withstand before rupture occurs.