Abstract: A cast-formed bi-metallic worm assembly of a mechanical screw press for expressing liquids from fibrous materials and a method of manufacture therefor and the product produced by the method. The worm assembly is rotatably driven by the press drive shaft and includes an outer flight body having an integral outwardly extending helical flight formed of a relatively brittle, wear-resistant homogeneous cast material and an inner hub tightly fitted and substantially fully mated within, and coextensive with, the outer flight body. The inner hub, cast formed of a more ductile, tougher homogeneous material, includes a hollow cylindrical interior surface structured for slidable engagement around and in driving connection with the drive shaft. The inner hub and outer flight body are securely engaged one to another by cast forming the outer flight body around the precast inner hub.

Abstract: A cast-formed bi-metallic worm in a mechanical screw press for expressing liquids from fibrous materials and a method of manufacture thereof. The worm is rotatably driven by the presses drive shaft and includes a body adapted to slidably engage around and be driven by the drive shaft and a flight extending radially outward from within the body. The body is formed of a ductal homogeneous cast material while the flight, which may be continuous or split, is cast formed of a harder homogeneous material so as to mechanically engage within and be rotatably driven by the body. The worm may also include a wear resistant cast-formed shell around the periphery of the body formed of either the same material as the flight or another hard wear resistant material.

Abstract: A drainage system for expressing liquids and fluids from fibrous materials. The system includes a plurality of spaced apart compression elements each retained in juxaposition one to another so as to have a fluid escape slot between each adjacent compression element. Each compression element has a longitudinal passageway therethrough each having an inlet and an outlet which is inwardly tapered toward its outlet. The combination of passageways through each compression element forms a compression conduit whose inlet and outlet generally functionally coincide with the intake and exit, respectively, of the drainage system. The fibrous material to be expressed is introduced into the system's intake under pressure, the fibrous material being compressed as it is forcably urged through each tapered passageway, the expressed fluids exiting the compression conduit radially outwardly through fluid escape slots.