Optimization of Conventional Combine Harvester to Reduce Combine Losses for Basmati Rice ( Oryza Sativa )

A study was conducted at PAU Regional Research Station, Gurdaspur (Punjab) to investigate the design and operational parameters of threshing mechanism of conventional combine harvester for basmati crop. This study was aimed to investigate the suitable changes required in the self-propelled conventional combine harvester for harvesting the basmati crop with minimum grain losses. Field evaluation of experiment was carried out to assess the influence of independent design variable i.e., arrangement of spikes (AS) and independent operational parameters such as concave clearance (CC) and cylinder speed (CS). The study was aimed to enumerate various combining losses viz., extent of visible and invisible grain damage and threshing efficiency at different AS, CC and CS levels. The first year data recorded during 2017 were processed for the optimization during 2018. The results of the present study revealed that during 2017, maximum visible and invisible losses was 5.49% ± 0.33% and 28.07% ± 3.21%, respectively whereas after modification, these losses remained only 4.00% ± 0.80% and 24.07% ± 2.86%, respectively. The threshing efficiency remained above 99.31% ± 0.47%, for both years. Thus, optimization of combine harvester was able to save the visible grain damage by 60% to 83% and invisible grain damage by 6% to 16%, respectively during 2018 than the year 2017.