Screw flight rear face

Face (of flight) The front face of a screw flight, oriented toward the feed hopper. The rear face of a flight, which pushes the molding compound, is oriented towards the screw tip... 

Leading flight face (leader flight). The forward or front side of the flight of an extruder screw, the rear side being the trailing flight face. 

Trailing Flight Face n (trailing flight) In an extruder screw, the rear side of any flight. The forward side is called the Leading Flight Face. 

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