The impact of different combine harvester regulations during the mechanical harvesting of forat rice variety

Abstract

The research was conducted at the Mishkhab research station to study the impact of differentcombine harvester regulations on the rice losses inflected by harvester units and the totallosses for the Class Dominater harvester .The forat variety which was verified by the ministryof agriculture was used in this experiment .However , the research consist of three factorswith three levels for each factor , these are : combine field speed are 1.7, 2.3 and 3.0 km/hr,threshing cylinder speed are 800,1000and 1200 r.p.m , cylinder concave clearance are 1.25,1.5 and 2 cm , the research performed as a factorial experiment at the RCBD design withthree replications.The forat rice crop variety showed a clear response to change combine harvester regulations.These regulations are combining harvester field speed, threshing cylinder concave clearancewhich were counted as the three main factors of this research. The results observed showedthat the losses of the each combine harvester unit and the total losses were changedsignificantly as the combine harvester field speed changed. The highest total losses ratio ofcombine harvester was 7.24% at the highest field speed (3.0km/hr). However this ratiodecreased at the other two combine harvester field speeds and the reason was the combine reelindex which was at its optimal condition. This reel condition coincided the combine fieldspeed with the reel speed and the result was a reduction in the combine platform losses andthis result reflected on the combine total losses .This phenomenon was observed particularlywith this variety because it is easily shattered.The results also showed that the effect of increasing the threshing cylinder speed or reducingthe cylinder concave clearance within the range of this research was identical interim of theresults achieved .However, it was observed that no significant effect of changing these factorson the combine platform losses, while a significant in losses was noticed in the threshing andseparation units. It was also noticed that no significant effect either the threshing cylinderspeed or cylinder concave clearance on the ratio of the total losses.The results of the interactions showed that the lowest percentage of the total losses forharvesting of forat varies was 4.72 % at 1.7 km/hr combine field speed 800 r.p.m threshingcylinder speed and 2.0 cm cylinder concave clearance while the highest total losses was 8.3 %at the highest combine field speed 3 km/hr, 1000 r.p.m threshing cylinder speed and 1.25 cmcylinder concave clearance.