An electrically operated kola nut pods breaking machine

Abstract

Kola nut pod breaking is a very tedious task manually; therefore its mechanization is essential for effective processing.  The objectives of this study are to design and fabricate a kola nut pod breaking machine and performance evaluation of kola nut pods breaking machine.  Some physical and mechanical properties required for machine design were determined using standard methods.  The machine was powered by an electric motor, with the hammer attached to the shaft using a drum with a rope tension of 171.68N, cross–sectional area of 5.027 x 10^-5m² and 3414.90 kN/m² tensile stress.  The speed of the machine used by the pulley was 308.57 r/min to operate. The machine was evaluated by using one to four pods at a time, and was replicated four times.

The average moisture content was 68.87% wet basis. The average length, breadth, width and thickness were 108.54±7.79, 60.60±13.31, 46.97±10.23 and 10.37±1.54 mm for large whole kola nut pods respectively.  The average mass, volume and density of whole kola nut pods were 0.154±0.071 kg, 1.475±6.071x10^-4m³, and 471.374±98.756 kg/m³, respectively.

The force required to break kola nut pods along its lateral axis was 2691.27±1030.74 N and 421.66±363.97 N for longitudinal axis. The energy needed to break a pod along its lateral axis was 19.78±10.27 J; and 7.617±2.798 J for longitudinal axis.  The lateral force and energy were more in both cases; hence it will be better to break the pod along its longitudinal axis.

A pod breaking machine with optimum machine capacity of 501.081 kg/h, maximum machine efficiency of 80.94 % and total cost of N40, 200 k was developed.