1. Operations of a Feeding Devices in Pneumatic Conveying Systems
A listing of some guidelines on the operation of feeding devices in pneumatic conveying systems can provide us with many suggestions for best operations.

2. Feeding Systems Feeding Systems A. Vacuum systems
Free Flowing material – orifice
Pick-up nozzle – control of both air and material
Feeder
B. Pressure systems
1. Fluid head pressure
a. Air lift
b. Fluidized feeder system
2. Venturi

3. 3. Rotary air lock
4. Rotary air lock, feeder
a. Design variations
1. Outboard bearings – for pressure use
2. Rotor – open end/closed end
3. Rotor – number of blades
4. Rotor-types of blades and materials
5. Housing-venting, side entry
6. Abrasion resistant

4. b. Application
1. Desirable speed rate rpm
2. Large enough throat not to restrict flow
3. Leakage air requires venting
Lock Hoppers/Gate Locks
Similar to a blow tank in operation

5. Diagrams of Feeding Systems
The following are some detailed diagrams on how feeders operate.

6. Design Points Feeder Control Internal Pressure
External Bearing on Feeding Valve
Venting

7. Design Considerations
Vacuum Conveying
Pressure
Conveying

8. Rotary Valve Operations
Sloped Entry
Feeding Deposit
Double feeders
Eliminates Venting
Issues

9. Blow tank arrangements

10. Pull-Push Pressure Tank