Effects of concave rod clearance and number of concave bars on threshing performance of a axial flow rice threshing unit for Chainat 1 variety (Thai)

Abstract

The objective of this study was to determine the effects of concave rod clearance and number of concave bars on threshing performance of an axial flow rice threshing unit for Chainat 1 variety which is difficult to thresh. The results indicate that the threshing unit losses decrease, the amount of materials other than grain (MOG) through concave bars increases, and grain damage decreases when the concave rod clearance is decreased. However, a clearance of 15 to 20 mm should be used when the losses and the MOG are taken into consideration. The number of concave bars did not affect the threshing performance.