الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 110 |  |  |
| | | from | 110 | | |
Abstract
Oil crops are considered one of the most important source of nutrition for millions of people all over the world. Sunflower is one of the most important oil crops in the world. It ranks second after soybeans with respect to oil production. It can be cultivated in the new reclaimed areas, and is adaptable to a wide variation of soil and climatic condition. One of the biggest constraints for increasing the production area of sunflower crop in Egypt has been the lack of suitable threshing machine. Also no specialized threshing machine for sunflower crop, it more times threshed by the Turkish threshing machine which depends upon the impact and shear forces which causing more damage for the sunflower seeds, in addition to the fleshy material of the head causing more problems.The main objectives of this study are :-1- Modifying and testing a sunflower threshing machine, That recombined the combination methods of impact and rubbing force.2- Studying the effect of some threshing conditions on machine efficiency and energy required.The developed machine was evaluated to thresh the sunflower crop at different factors affecting the threshing operation such as the following:-1- Drum peripheral speed at four different levels of about 4.58, 6.41, 8.24, and 10.07 m/s,2- Concave clearance at three different levels of 2.5, 3.5, and 4.5 cm,3- Impact plates numbers at two levels at ( 12 and 24 plates on drum ),4- Heads moisture content at three different levels of about 11.28, 15.67, and 19.09 % w.b.the main results obtained from the study can be summarizing as the following points :1- Threshing losses were increased by increasing the concave clearance and the moisture content, and decreased by increasing the impact plates numbers and the drum speed. The lowest value was 0.31%, and the highest value was 36.16%,2- Threshing efficiency were increased by increasing the impact plates numbers and the drum speed, and decreased by increasing the concave clearance and the moisture content.The lowest value was 63.84%, and the highest value was 99.69%,3- Visible seed damage were increased by increasing the impact plates numbers, the drum speed, and the moisture content, and decreased by increasing the concave clearance. The lowest value was 0.09%, and the highest value was 9.41%,4- The productivity of the threshing machine increased by increasing the impact plates numbers, the drum speed, and the concave clearance, and decreased by increasing the moisture content. The lowest value was 0.26 Mg/h, and the highest value was 0.669 Mg/h,5- The required power for threshing operation increased by increasing the impact plates numbers, the drum speed, and the moisture content, and decreased by increasing the concave clearance. The lowest value was 4.80 kW, and the highest value was 7.53 kW,6- The consumed specific energy increased by increasing the moisture content, and decreased by increasing the impact plates numbers, the drum speed, and the concave clearance. The lowest value was 8.3 kW.h/Mg, and the highest value was 25.76 kW.h/Mg,7- The cost of sunflower threshing using the modified thresher increased by increasing the moisture content, and decreased by increasing the impact plates numbers, the drum speed, and the concave clearance. The lowest value was 122.5 LE/Mg and the highest value was 238.5 LE/Mg.