Effect of Threshing Cylinder Configuration on Wheat Straw Quality in Indo-Gangetic Plains

Abstract

The threshing on Indian farms is required to make and collect both grain and chaff for human and cattle consumption, respectively. This criteria of wheat bhusa making led to unacceptability of combines and the simultaneous development of threshers which not only separate grain but also deliver wheat straw in size of 10-20 mm length. The wheat straw size for maximum output capacity and maximum threshing efficiency were 22.43 mm and 22.67 mm at tip diameter of 600 mm and spike thickness of 6 mm corresponding to maximum feed rate (780 kg/h) in case of rectangular spiked and round spiked threshing cylinders. For higher threshing efficiency, fine straw quality and minimum specific power consumption, rectangular spiked threshing cylinder of 600 mm tip diameter and spike thickness of 6 mm have given best performance results with total grain loss within permissible limit. The spike thickness of 6 mm gave minimum broken grain loss with fine straw quality. The round spiked (plain spike) threshing cylinder with same configuration of threshing cylinder showed best results. But from mass manufacturing point of view, tip diameter of 600 mm and 8 mm round spike thickness will be appropriate for manufacturers. It also delivered good output capacity and threshing efficiency and fine straw quality.