BigPatents India

The invention relates to an extruder for continuously processing and/or treating free-flowing substances, comprising at least two parallel shafts that rotate in the same direction. Said shafts are fitted with intermeshing screw elements, whose face is delimited by arcs of a circle, which correspond to the outside diameter of the screw, to the core diameter of the screw and, at most, to the axial distance of the screw elements, and which are guided on circular segments of the extruder housing that are parallel to the shafts. At least one screw element (1) comprises a number of interspaced concentric annular sections (8) that are formed by recesses (12) in the screw element (1). (FIG1).