Lecture 19 Augers, Bucket Elevators & Componets

Receiving Pits and Hoppers Key design considerations: 1) able to unload in specific period of time 2) width must accommodate unloading width 3) angle at least 45 degree angle, if powder like material, then at least 60 degrees

Pit capacity PITCAP = M * (VUR - GRRP) pitcap = capacity of pit M = max time to unload in minutes VUR = max delivery vehicle unloading rate- bu/min. GRRP = grain removal rate from pit - bu/min

Pit Considerations Top Surface Dimensions Rule of thumb - distance between wheels Design issues - p. 264 ideally, top dimension = width of tires square with this being the outside dimensions of the pit... Unloaded by auger... p. 266 Unloaded by gravity... p. 267 Other pit considerations conveyer belt should be locked in the event that the conveying mechanism ahead of it stops. can you clean it? (Easily?) type of grating sump pump if needed height to raise bed of truck

Wet holding Bins Ability to hold grain for one day depends on type of drying system Filling the wetholding bin... filling rate a function of incoming conveyer if inflow less than drying rate, small bin needed lock electrically to prevent blockage gravity flow is great advantage forms a natural hopper needs to be cleaned daily needs another way to empty bin than through the dryer (bypass the dryer

Continuous Flow WHCAP = (HR - DR) * HTIME - PCAP WHCAP = wet holding capacity HR = max bu/hr harvesting rate DR = potential drying rate in bu/hr HTIME = time that harvesting occurs (hr) PCAP = capacity of pit (bu) *Note: this assumes that it will be empty each day

Pneumatic conveyers Advantages: Reach out of the way locations well suited for flat storage facilities dust and shoveling are minimized mechanical parts are at ground level units are self cleaning & safer to operate Disadvantages: energy requirements are higher almost always tractor PTO driven almost always more noise damage occurs to grain above 4,000 ft./min

Pneumatic conveyers Types- positive negative combination