Topics in Processing

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Topics in Processing

• Materials Handling

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Assignment
• Read Chapter 8 handout

Dr. C. L. Jones Biosystems and Ag. Engineering
3
Materials Handling

• All manufacturing facilities, elevators,
  feed/food processing centers, retail stores,
  warehouses, have handling devices
• Classification
• Belt conveyors
• Chain conveyors
• Screw conveyors
• Bucket conveyors
• Oscillating conveyors
• Pneumatic conveyors
• Gravity conveyors
• Cranes
• Lift and carrying trucks and carts

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Belt conveyors
• Endless belt between two or more pulleys
• High mechanical efficiency
• Antifriction bearings
• Little material damage
• High capacity
• Long service life
• Low cost

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Belt conveyors
• Belt carries the load
• Drive
• At the discharge end
• Usually a belt drive
• Tension or take-up
• Takes up the stretch in the belt due to
  contraction/expansion

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Belt conveyors
• Idlers
• See Fig. 8.1
• Loading device
• Hand fed
• Mechanically fed
• Continuous or intermittent flow
• Discharge device
• Over the end of the belt
• Diagonal scraper
• Tilting
• Tripper.Fig. 8.2

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Belt conveyors (Fig. 8.3 and Table 8.1)
• Surcharge angle and belt selection (ex. pg 204)
• HP to drive empty conveyor (eqtn. 8.1, 8.2,
  8.3)(ex. pg 205)

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Chain conveyors
• Cheaper than belt conveyors
• Noisy
• Slow
• Not efficient
• Versatile
• Good for intermittent operation

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Chain conveyors
• Trolley
• Overhead track
• Can make sharp turns, steep inclines
• Scraper
• Used for granular products
• Can make steep inclines
• Power requirements and wear are high
• Fig. 8.6
• Apron
• Like scraper with flat slats, steel plates or
  boards.
• Used for conveying sacked materials and large
  unit sizes

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Screw conveyors
• Used to handle fine materialspowders, granular
  materials, sticky viscous materials
• Simple
• Inexpensive
• High power requirements
• Limited in length
• Inclines up to 20 degrees
• Horizontal
• Inclined
• Less efficient mechanically and volumetrically
• aka augers

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Bucket Conveyors
• Classified as either belt or chain or both
• Range from simple to large, expensive
• Fig. 8.8
• Centrifugal discharge small grain
• Perfect-discharge slow speed, cheap, handles
  delicate material well
• Continuous bucket heavy duty use, ores,
  sanddischarges by sliding over bottom of
  preceding bucket
• Two variations of buckets Fig. 8.10
• Equation 8.11 for HP

Dr. C. L. Jones Biosystems and Ag. Engineering
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Materials Handling

• Wednesday
• Meet in Ag Hall
• 330 to 420
• More conveyors

Dr. C. L. Jones Biosystems and Ag. Engineering