B2CH-13-C d Nominal power ratings PN kW type B continued Ge Bevel-helical speed reduction gearboxes B2

Flender/Flender Gear Units/Bevel-helical speed reduction gearboxes B2

me-scale operation. In the community- or village-level operation, hand-operated wooden or stone grinders are still in use. With the progress in mechanical and electrical appliances, power-operated grinders (either horizontal or vertical) have come into existence for small com-mercial-level operations. Large-scale commercial mills normally employ emery-coated horizontal rollers (ta- pered or cylindrical) along with appropriate separation systems (see Fig. . Many such mills are in operation in India and other Southeast Asian countries. Nearly 7 such mills are working in India alone. However, manufacture of milling machinery is not anorganized industry, but is of localized nature. Normally, the mills are fabricated bylocal artisans in the areas. The power requirement, capacity, operating parameters, andspecications of the machinery vary from place to place, often decided by local artisanswho have experience or expertise in this trade. But many fabricators depend on the trial-and-error approach, which leads to wastage of resources and lower yield of product. 2.3 Pulse-Milling Machinery: Current Status Conventional pulse milling involves many unit operations, such as cleaning the raw mate- rial, size-grading, scarication of husk (pitting), oil mixing, water mixing, drying, dehul- Milling of Pulses 4 ling, splitting, aspiration of husk, separation of brokens and splits, and nally, polishing. The different types of machines used for each unit operation are discussed here in. 2.3.1 Two Types of Mills Are in Vogue in IndiaOne, which is very common in northern parts of India, is characterized by two-storied setup similar to the roller our mills. This type saves space and the number of elevators required. The second, which is more common in south India, is essentially single-storiedtype, in which the material moves horizontally from one unit to the other through bucketelevators. In this system more elevators and space are required. 2.3.2 Cleaning and Size-Grading Systems