Bevel-helical gear units B3 and only iN Size only iN Shaft versi B3-VV-14B

Flender/Flender Gear Units/Bevel-helical gear units B3

orage and subsequent curing operations. The wet parchment coffee has water content of around5%5%, which has to be reduced to 1%. In preparation of cherry coffee, the moisturecontent of 6% in fruits is reduced to 1% for safe storage. 3.4.1 Sun Drying Most of the worlds coffee is dried in sun, although the present tendency is to dry more and more in mechanical dryers because of rising labor costs, unfavorable weather, andthe goal of obtaining uniformly dried beans. Freshly pulped and washed coffee usuallycontains 5% to 5% moisture. After draining of excess water, beans are spread on thedrying terrace. The thickness of the layer is usually 2 in (5 cm) and coffee is raked at frequent intervals during daytime. To prevent uneven drying and cracking of the parch- ment during intense heat or sunshine, the coffee beans should be covered or dried in shade;in the case of cherry coffee, the fruits are heaped for 1 or 2 days to allow softening andthen dried in open yards. Fruits are dried up to moisture level of 1%; drying may take about 1 week for washed coffee and about 3 weeks for natural coffee (. 3.4.2 Machine Drying Generally, machine drying consists of passing hot air through bed of coffee. Two meth- ods used are through-ow and cross-ow drying; through-ow drying is much more ef-cient. It is good practice to use drying air at temperature of 6 in the rst stages of drying and slowly decrease the temperature. In mechanical drying, heated air is passed through bed of coffee, which is stirred constantly by either rotating the container or using rakes or conveyers. One of the simplest instruments consists of wire screen or perforated metal on which coffee is loaded andheated by passing hot air through it. Loading, unloading, and stirring are carried out manu-ally. There have been several improvements in the design and operation of dryers, suchas automatic loading and unloading, rotating power-driven rakes, recirculation of hot air,and furnaces that accomplish smokeless