Transcript Slide 1

Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
• Screw Conveyors: Page 213
– Capacity calculation: pg. 214 eqtn. 8.5
– Table 8.3 and 8.4 capacity data and material
classification
– Equation 8.6 for HP
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
• Bucket elevators
– Figure 8.8 page 219
• Centrifugal discharge for small grain
• Perfect discharge: low cost, slow
moving, low damage required
• Continuous-bucket type: heavy duty
use such as ores, sand, rocks.
Material slides over preceding bucket
bottom
• Read section in handout.
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
•
Bucket elevators
A bucket elevator has 36 buckets similar to the
configuration in Fig. 8.10(a) and a lift of 73 ft.
Calculate the HP.
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
• Oscillating conveyors (page 223)
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
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Pneumatic conveyors (page 224)
Figure 8.14
Uses fans, vacuums, and conduits
We will work a problem on Friday for this kind
of conveyor
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
• Gravity conveyors
• Consist of rollers or wheels set on a level or a
slight incline.
• Material is moved by hand or by gravity.
• Intermittent service
• Used as a support aide with external power.
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
• Cranes, trucks and carts
• Cranes are not used extensively in ag
services but are used largely for construction
• Trucks, fork lifts and carts:
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Used in warehouses and shipping units
Generally handle large bulky items
Can handle variable location items
Must consider labor efficiency and time/motion
studies
– Included would be bale spikes and some bale
loaders
Dr. C. L. Jones
Biosystems and Ag. Engineering
Lecture 20 – Materials Handling
(Chpt 8 Henderson/Perry)
Example:
A bucket elevator has buckets similar to the
configuration in Fig. 8.10(b). The belt speed
is 35 ft/min and there are 52 buckets on the
belt. The lift is 92 ft. Calculate the HP.
Dr. C. L. Jones
Biosystems and Ag. Engineering