Lecture 20 Conveyors

Grain Spreaders  most common = spinner  most = electric motor driven  some use rotating auger  some natural drop of grain  fines tend to fall in one place  restricts air flow through this area  no hand leveling needed

Chain Conveyers  (Also called flight or drag)  if at bottom of conveyer = drag  if at top of conveyer = flight  operate at less than 200 ft/min  quieter than an auger

Power requirements: Hp = 2 * V * LC * WC * FC + Q * (LL * FM + HTDC) 33,000 V = velocity of chain (ft/min) LC = horizontal projected length of conveyer (ft) WC = weight of flights and chain (lb/ft) FC = coefficient of friction for chains and flight Q = quantity of material to be handled (lb/min) LL = horizontal projected length that is "loaded" (ft) FM = coefficient of friction for material(table 6.10) HTDC = discharge height (ft)

Power requirements Projected conveyer length LC = COS (c) * TCL c = angle of elevation of conveyer TCL = total conveyer length Material to be handled BPH = Bu / hr capacity BD = Bulk density of material (table 6.1) Projected horizontal conveyer length LL = COS (c) * TLL Discharge height HTDC = SIN (c) * TLL TLL = total loaded length of conveyer

Belt conveyers - elevators  very efficient  relatively expensive  low damage levels  seed conditioning systems  high carrying capacities  greatest angle of elevation for grain = 15 = 17o

Capacity BLTCAP = 48 * CSA * BLTS BLTCAP = belt conveyer capacity (bu/min) CSA = Cross sectional area (ft2) BLTS = belt speed (ft/min) three rollers (determines belt capacity) flat can be used (reduces capacity)

Total belt width = THW = CW + COS (rola) * (TBW-CW- 2 * M) THW = Total horizontal width of belt TBW = Total Belt width CW = Center width rola = angle of rollers M = margin clearance on each side of the belt