Screw conveyor in pulp-making equipment

Claim 1

A screw conveyor for use in pulp making equipment for advancing a mass of pulp material from a material-supply station to a further-processing station, in an environment of pressurized steam while being gradually compressed into a steam-tight plug by the progressively increasing force of the advancing material, comprising: (a) a horizontal casing having a conical bore tapering from a material inlet end to a material outlet end; (b) said casing being split vertically into two equal components clamped together along their bottom portions, the top portions each having an upwardly flange defining a slot therebetween; (c) a rotatable screw feeder extending through the conical bore of the casing, comprising helical flights and an intervening spiral groove and conforming to the inner diameter of said conical bore for advancing the material from the material inlet to the material outlet while being gradually compressed into a steam-tight plug; (d) a sprocket wheel having teeth contoured to conform to the profile of said spiral groove for successively engaging the spiral groove synchronously with the screw feeder and mounted rotatably in said slot in frictional contact with said flanges for preventing the material from turning with the screw feeder during the advancement and compression thereof; and (e) means for maintaining said flanges in frictional contact with said sprocket wheel.