SOME PHYSICAL-PROPERTIES OF OILBEAN SEED

As the initial stage in developing a machine for dehulling oilbean seeds, some of the physical properties of the seeds relevant to dehulling were measured. At a moisture content of 4·5%, dry basis, oilbean seeds have a major diameter ranging from 60 to 70 m and thickness ranging from 9 to 19 mm. A low average sphericity of 0·60 and roundness of 0·4 are characteristics unfavourable for rolling of the seeds to take place. With an average density of 1·12 g/cm3, the seed is unable to float in water. The static coefficient of friction varied from 0·299 on glass to 0·425 against plywood with the wood grain perpendicular to the direction of motion. The angle of repose was 17 deg. Hardness varied from 48·8 to 87·4N and crushing energy varied from 0·5 to 2J. Specific heat capacity was highest for the lighter seeds and lowest for heavier seeds. © 1991 Silsoe Research Institute.