DESIGN, FABRICATION AND TESTING OF A MAIZE SHELLER

ABSTRACT

This project involved the design, fabrication and testing of a maize sheller. A maize sheller is a machine that removes the maize grains from the cobs. Though many shellers have been developed and made available locally to the farmers, their prices are not pocket friendly thus making many farmers shy away from buying the shellers. A lot of farmers thus resort to manual shelling which is characterized by high costs of labour and low outputs.

Through this project, we were able to develop a cheap and an efficient sheller which could be easily afforded by small scale farmers. The sheller was designed using a CAD software known as solid works. The designed sheller was then fabricated in the University of Nairobi workshop using locally available materials.

The fabricated sheller was then tested in the workshop with maize for a period of 22 seconds and its output noted. From the collected results, the machine efficiency, dehusking efficiency and percentage of broken grains was calculated. The obtained results were then analyzed and it was concluded that although the sheller had a shelling efficiency of 100% and a broken grain percentage of 15%, the broken grain percentage needed to be reduced to about 5%.

The budget of the sheller was 35750 ksh. This value is low compared to the prices at which other shellers were retailing in the market at figures of about 60-70, 0000 ksh. Hence this sheller can be afforded by small scale farmers.