H3-VH-7-D redutores flender Helical gear units H3

Flender/Flender Gear Units/Helical gear units H3

ck box dryers. These use heater fan unit, similar to that used for bin drying, that is connected to smaller air ducts suspended at midheight of the box or located on its oor. If suspendedair ducts are used, exhaust ducts on the oor are necessity. These types of automatic dryers are equipped with thermostats or timers to control heating and unloading cycles and can be completely automated if mechanized grain-handling system is used. 3.3.2 Recirculating Dryers Portable recirculating batch dryers are essentially the same as nonrecirculating models except that they have central auger that picks up grain near the bottom of the columnand deposits it at the top (Fig. . complete recirculation of grain occurs roughly every 1 min. Most common dryers of this type come in sizes ranging from 1 to 1.5 3(3 5 bu) bin capacity. These dryers are often used by medium-sized of farms in eastern Fig. 7 Typical portable dryer. 1 Raghavan Table 2 Recommended Drying System Based on the Annual Farm Production at Harvest Annual production (ton) Type of drying system 2 Natural air drying 6 Natural air drying with supplemental heat 4 Batch-in-bin dryersAbove 1 Portable and continuous ow dryers North America that cannot afford more expensive continuous-ow model. The dryers may be used for virtually any crop, if the maximum safe drying temperature is not ex- ceeded. However, their disadvantage is that constant augering can cause damage to certainseeds, such as beans, peas, and malting barley, especially when they are nearly dry. 3.4 Dryer Selection Selection of continuous-ow, batch, or batch-in-bin dryer depends largely on the amount of grain to be dried and the facilities farmer already has available when the dryer is purchased. For example, farmer who already has good-sized storage bin and only small volume of grain to store would likely use an in-storage dryer, rather than purchase portable dryer and wet grain holding bin. In-storage dyers usually are suitable onlyfor farms harv