Studies on Fan Type Thresher (I)

Abstract

Research descrived in this paper was conducted to investigate the threshing efficiency of rice and rice threshing power requirment of a fan type thresher. The fan type thresher is a radial-flow threshing apparatus, constructed of rotating metallic fan and its housing.
Tests were conducted with two fans to determine the effect of the fan speed and the axial clearance upon the threshing efficiency, threshing loss, power requirment and the feeding and transport characteristics of grain and straw.
With the increase of the threshing fan speed the threshing efficiency increases, but the damage of the paddy increases rappidly more than 2000 r.p.m. For the good feeding of straw to the thresher the suction air velocity must be more than 30m/sec. The percentages of perfectly threshed grain are 80-90%.