A motorized device for cracking pre-treated dika nuts

Abstract

Cracking of dika nut has presented serious challenges to local processors considering the arduous task it constitutes during processing.  A motorized machine that is capable of multiple cracking of dika nuts was designed, fabricated and tested. The major components of the machine include a sliding hammer, a gear unit, a chain conveyor and cracking trays.  The experimental machine was evaluated on the basis of cracking efficiency and throughput considering three types of pre-treated nuts (sun-dried, oven-dried and roasted) and two nut sizes (small and big).  The cracking efficiency and throughput were: 65% and 8.84kg/h, 63% and 7.75kg/h, 45% and 5.67 kg/h for roasted, oven-dried and sun-dried small nuts; while the corresponding values for big nuts were: 72% and 12.86kg/h, 70% and 12.58kg/h, 67% and 12.41 kg/h, respectively.  Big dika nuts indicated a higher cracking efficiency and throughput than small nuts. The highest cracking efficiency and throughput values (72% and 12.86 kg/h, respectively) were obtained for big roasted nuts.  The method of pre-treatment and dika nut sizes were found to affect the cracking efficiency and throughput of the motorized dika nut cracking machine.  With a throughput of 10 kg/h and the possibility of cracking twenty nuts at a time, this machine is an improvement over existing designs.  A machine of this nature will be suitable for small and medium scale applications in the processing of dika nut.