A minimum screw clearance of 2.5" is used. All screws are constant diameter with variable pitch. The pitch
increases in the direction of flow. A shear plate is used at the discharge to maintain a fixed
discharge area. A thrust bearing on each screw keeps the screw in tension to
prevent buckling. The front wall is designed to withstand the force produced by
the shear plate. Screw flights are a minimum of 0.375" thick and barrels are a
minimum of Schedule 80. A maximum of three screws are driven by one drive
assembly. Removable panels are included for expedient removal and
access to the screws. Inspection doors are provided to observe drive hardware and
internal components. Screw sets are driven counter to each other to help centralize
the bark pile.
