No abstract

Threshing losses (%), separating losses (%), shoe losses (%) and threshing efficiency (%) were calculated and determined in this investigation as the parameters required for evaluating the performance of the modified threshing device of a cereal crops harvester with the aim to reduce threshing and separating losses and reduce damaged seeds. The main characteristics of the used harvester were CICORIA -T type, longitudinal axial-flow with standard 5 bats reel. The modification was accomplished by replacing the wrapped rasp-bars by shaped prismatic beaters made from steel and fixed (bolted) tightly on the same (6) lines of the original rasp-bars. The factors considered to test and evaluate the performance were combine forward speed of 2.40, 2.82, 3.30, and3.80 km/h: seed moisture content of 22.35, 15.15 and 10.75(%wet basis): threshing rotor speed of 9.14, 10.43, 11.73 and 13.49 m/s and concave-rotor clearance ratio of 4.2/2.8and3.25/2.5 .The direction N  S (North-South) was used in sunflower seed crop harvesting as suggested in a previous study. The results revealed that the least values of threshing, separating and shoe losses were about (0.18% or 2.31 kg/fed), (0.14% or 1.8 kg/fed) and (0.11% or1.61 kg/fed) respectively at the forward speed of 3.3 km/h, clearance ratio of 4.2/2.8 and seed moisture content of the range from 10.75 to 15.15 % wet basis. Rotor speed of 13.49 m/s (379.27 rpm) realized the least values of both threshing and separating losses at the previous conditions, while the least values of shoe losses were achieved when the rotor speed decreased from 13.49 to 9.41 m/s at the same previous conditions. The lowest value of 0.73% processing losses (threshing, separating and shoe losses) of the total yield was occurred under 1.5 concave clearance ratio, rotor speed of 11.73 m/sec and 15.15% seed moisture content

Some essential parameters (header losses %, length of cut neck cm, head pulling before cutting % and header efficiency %) were measured in this investigation when harvesting sunflower crop at seed moisture content of 22.35, 15.15 and 10.75 %wet basis , combine forward speed of 2.40, 2.82, 3.30, and3.80 km/hr, reaping direction with the directions: d 1 = N  S, d 2 = E  W, and d 3 = W  E. Based on these parameters ,the header system for a cereal crops harvester (longitudinal axial-flow , with standard 5 bats reel (T) type CICORIA combine harvester was modified and tested. The demonstrated results for the tests showed that the suggested harvesting direction was d 1 . Simultaneously, at all the investigated directions the moisture content of the sunflower seeds had a positive relationship with head pulling before cutting % and header efficiency % while reversible correlation was found with the length of cut neck cm and the header losses % . Also, both the header losses % and the head pulling before cutting % increased as increasing combine forward speed with the modifying header.

The performance of a small modified European grain combine harvester CICORIA, in harvesting sunflower Crop was investigated. Effects of some important parameters such as combine forward speed, seed moisture content, harvesting direction, rotor speed, and rotor-concave clearance on the combine performance were studied. Results showed that the optimum condition obtained at forward speed of 3.3 km/h, seed moisture content of 15.15% (db) Results also indicated that total seed loss of 40.02 kg/fed, energy requirements of (11.38 kW.h/ton), seed production of 1739 kg/h, fuel consumption of 5.5 L/h and total combine processing efficiency of 97.27% were obtained .