Bevel-helical speed reducer B2 sign of the gear units Overview tables Technical s B2HH-16-C

Flender/Flender Gear Units/Bevel-helical speed reducer B2

mplete scarication is effected. After each operation the husk andpowder are separated. The scaried grains are then mixed with about 0.5% oil and heapedovernight for absorption. The grains are then sun-dried for 2 days. In some mills mechani- cal dryers are used. After drying, the grains are given spray of water (2%), equili- brated, and passed through the rollers twice for dehusking. The splits obtained are termedsecond-grade dhal. The dehusked whole grains are either marketed as such at certain placesin India or passed through Burr mill for splitting. These splits are considered rst-grade.The splits are polished with soapstone powder at the nal stages. This is believed togive luster and enhance their market value. 2.1.4 Green Gram The husk of green gram is thin, soft, and slippery. Although the husk tightly adhers to the grain surface, the two cotyledons are loosely attached and separate out easily. Hence,splitting occurs even before good dehusking can be effected. During the dehusking opera-tion, there is also scouring of the cotyledons, resulting in large losses in the form ofbrokens and powder. The method generally followed is pitting, oiling (0.2.5%), and sun-drying, followed by dehulling and splitting in roller machines. 2.1.5 Peas and LentilThe milling of these pulses is fairly easy as found for chickpea. General practice involves initial scouring, application of water, heaping, and sun-drying, followed by dehusking and 4 Narasimha et al. Fig. 7 Traditional dhal mill. splitting in roller machines. After separating the splits, unhusked grains are treated again for second time as in the rst pass, and the process is repeated until all grains aredehusked and split. 2.2 Pulse-Milling Machinery (Traditional) Pulse milling being an age-old industry in Asia, particularly in Bangladesh and the Indian subcontinent, simple mechanical devices such as pestle and mortar or leg-operated pestleand mortar ( dhenki ) were in use about three decades ago, particularly for ho