flender de H3DH-24-C Helical gear Reduction Box H3

Flender/Flender Gear Units/Helical gear Reduction Box H3

eal crop harvesting under the prevalent sociotechno-economic conditions and help in increasing the production and the productivity of thecrop. 3 THRESHING The prime objective of the threshing process is to detach the sound or undamaged grain kernels from the plants. In some crops, it also involves the removal of kernels from the protective cover, called husk or pod. It is achieved by striking, treading, squeezing, tearing, and rubbing actions or by combinations of these methods. Traditionally, threshing is per- formed by treading the grain under the hooves of animals, striking the grains with sticks,beating them over log of wood or bamboo grating, or over ladder, or using stationarypower thresher of specic design for each crop, or between the rasp-bar and concave ofa combine. The machine used for the purpose of grain detachment and separation is calleda thresher and was introduced in India about 1. Timely preparation of seedbed and sowing of seasonal crops immediately after har- vest are the prime desire of all the farmers. To meet these requirements, threshing either needs to be delayed or the farmers are required to use stationary thresher. Delayed threshing will cause not only spoilage of grain, but will also increase the breakage percent-age during milling. Hence, the use of stationary thresher, faster method of grain detach- Harvesting and Threshing 9 ment and separation for cereal and pulse crops has become very common among all groups of farmers. Stationary threshers are conventionally used when the elds are small andconditions are not favorable for combine operation. For speedy and effective threshing,pedal- and power-operated threshers are used, respectively, by the small to marginal- andmedium-class farmers. With the use of these threshers, threshing of most crops and separa- tion of grains and seeds from unthreshed debris has become mechanized in all developed and underdeveloped countries. 3.1 Traditional Threshing Conventionally, harvested paddy and