The present study aims to modify and develop a small, simple, and cheep machine for cleaning and grading Egyptian crop seeds by using both mechanical and aerodynamic methods, suitable for the small village. The developed machine was constructed locally from available material which purchased from domestic market and fabricated to ensure low initial cost and availability of spare parts and ease cleaning and repair. The parameters involved in grading machine and analysis the behavior of particles and forces acting during grading process, to achieve the optimum conditions for cleaning, grading and conveying operations. To evaluate the performance of the modified cleaning and grading machine, a series of experiments were carried out to study some parameters, such as the effect of screen oscillation speed inclination, Broad beans (Giza 461); grading operations. The main results obtained from the experiments were summarized in the following main points:-
Te average mas of 1000 kernels 7579, Length 14.7 mm, width 11 mm, thickness 6 mm, specific density 1.28 g/cm3, projected area 2.15 cm2, terminal velocity 12.4 drag coefficient 0.396, Reynolds number 1170, and spherically 0.66 at M.C 14-18%. Separation efficiency was 98% at screen oscillation 2/5 rpm, Zero deg. feed rate 250 kg/h. Grain recovery was 99%, grain loss was 0.70%, and grain clean lines was 98% at the same conditions.