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Differential Feed Screw Design Benefits
- Alternative to twin screws.
- A forward feed helix and a reverse feed helix concentrically mounted to the same shaft.
Differential Feed Screw Design Benefits
* Large diameter screw prevents "boring" through product. Defeats product bridging over feed screw.
* Differential action between fights produces low flow rates with a high screw RPM.
* Discharge from feeder is uniform and pulse free.
Problem:
* Small capacity feed screws with small diameter (and pitch) prevent uniform and reliable filling of screw flights.
* Large feed screws with large pitches provide uniform filling of screw flights but create large material discharge pulsation when feeding at low feed rates.
* Small feed screws installed in a feeder designed for large feed screws create material "dead zones" where stagnant material builds up resulting in flow blockage and preventing complete clean out of the feeder.
* Typical small diameter feed screws of both single and twin screw design are fragile, easily damaged and generally unreliable in heavy industrial process applications.
Solution: Thayer Scale's Patented Compound Flight Feed Screw
* Large pitch of screw's outer winding assures reliable and complete filling of screw flights.
* Screw's differential feeding action assures consistent, precise and reliable feeding of material without pulsation.
* Large over-wind matches (screws) feed chamber and tube diameter eliminating dead zone areas. No material build-up occurs. Assures reliable flow and complete clean out of material.
* Solid flight screw with robust over-wind assures reliable performance and long term durability in harsh process envirenments.
