الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Annually, Egypt cultivates around 1.8 million feddan of wheat and 800.000 feddan of paddy rice. The harvesting system for both crops primarily consistsof mannual cutting,
mowing, gathering and transporting the crop to one location, which causes losses up to 25
%in the field.Improving this harvesting system has been a main national objective. To
assist with this task various combines, mowers, reapers and threshers have been
introduced throughout the last decade.
The main objectives ofthis work are:
a- Define the thresher component which hinders capacity.
b- Redesign components to increase capacity.c- Estimate the power required for operation.
d- Test and report machine performance.
This research work was conducted as a USAIDINARP project and carried out at the
Agricultural Engineering Department of Purdue University, West Lafayette, Indiana of the
U.S.A.
This research was intended to improve the stationary thresher as a multi-crop
thresher tool, for wheat and paddy rice under Egyptian condtions. It was designed to
provide an optimal performance machine for small farmers. This techniques used, included
developing a new cylinder, can thresh wheat and paddy rice without major changes. Also,
the shape of the louver fins was modified and improved. Study of operating ranges
determined the thresher capacity and results showed it increased for wheat, soybean and
com without affecting seed quality (i.e. damage and losses).
This research contains results on three feed rates, optimum cylinder speed for
threshing different crops, moisture content, separation efficiency, material movements
along the rotor cylinder, and power required kW for the thresher. No-load data of each component of the system was taken. Also, the the power required kW at various wheat
feed rates was determined.
Important results could be summarized as follow:
- By attaching a conveyor belt to the thresher, the crop throughput increased to
3600 kg/h for wheat, 2400 kglh for soybean and 6000 kgIh for com.
- The new design thresher cylinder improved the threshing performance for wheat,
soybeans and com. Grain loss and grain damage within ASAE Standards. Also, grain
purity was 99 %.
- The optimum cylinder rpm for threshing wheat was determined to be 800 rpm, for
soybeans 300 to 400 rpm and 350 rpm for shelling com.
- The clearance between cylinder and concave used was 18 mm and cleaned successfuly.
- The slotted concave performed better in threshing high moisture content crops
than the 18 mm round holes.
- The theoretical calculated time of the crop in the threshing section was 0.8 second, but
the actual time of the crop in the threshing section was measured to be 2 second.
- Determination of power required for each component at different feed rates and
cylinder rpm was accomplished to aid design engineers in modifying and optimizing this
unit further.
- The straw fan needs to be redesigned to throw the straw further.
- This project was deemed successful in developing intermediate mechanization
technology.
- The new design of the thresher cylinder should be extensively tested in many different
crops under Egyptian conditions.
- The new thresher machine’s performance and economics benefits should compare
with other existing threshing systems under Egyptian Agriculture conditions.