Investigation of the Effective Factors on Threshing loss, Damaged Grains Percent and Material Other than Grain to Grain Ratio on an Auto Head Feed Threshing Unit

Abstract

Problem Statement: Regarding to considerable production of rice crop in Iran, study and investigation about optimization of different stages of this product processing seems necessary. The threshing of rice is a process which must be accomplished desirability. Approach: In this study, the effective factors effects on threshing loss, damaged grain percent and Material Other than Grain (MOG) to grain ratio, were investigated on a head feed threshing unit. Independent variables were included speed drum in five levels, variety in two levels and moisture content of crop in two levels. Experiments were arranged as a split-split plot fitted into randomized complete block with four replications. Results: Results showed moisture content of crop, variety and speed drum factors had significant effects on threshing loss, damaged grains percent and MOG to grain ratio. The means of threshing loss and damaged grains percent were excessive when the tests were doing with dry crop. The most of means of threshing loss and damaged grains percent were allocated to Hashemi and Khazar varieties, respectively. The most of MOG to grain ratio means obtained when the tests were accomplished with Hashemy variety at wet condition of crop. Conclusions/Recommendations: The optimum of drum speed was obtained 650 rpm. It is better that threshing of paddy has been conducted in wet condition. Increasing of drum speed increased the MOG to grain ratio significantly.