Factors Affecting Shelling Efficiency and Grain Breakage of a Small Maize Shelling Unit

Abstract

Abstract Development of a small maize shelling unit necessitates a study of factors affecting its shelling performance. In this study, the threshing type used is a rasp-bar type. On drum four rows with a diameter of 0.3 m, the design parameters of which include concave clearance. The peripheral speed of the drum, and grain moisture content; which affect the shelling efficiency and the amount of grain breakage. The maize used to be the CP 201 variety. The feed rate was controlled at 960 kg.hr−1. It was found that concave clearance and grain moisture content significantly affects the shelling efficiency and grain breakage at P<0.01. The peripheral speed of drum also affects the shelling efficiency but does not affect grain breakage. For good performance, we recommend concave clearance of 10.0 mm, peripheral speed of drum of 12 m.s-1 and grain moisture content not exceeding 14%.