Study on Design Theory of the Twin Screw Refining Mechanism

Twin screw refining extruder(TSRE) is a new type of high concentration refining equipment with characteristics of energy and water saving.However,there is lack of theoretical basis of design of the TSRE.Based on design theories and methods of co-rotating twin screw extruder in plastics industry,according to refining mechanics of the TRSE,this paper systemically investigates the design theories and methods including design flow of twin screw refining mechanism,output estimation,positive and reverse thread design and structure design of screw and barrel etc.Among them channel depth,centerline distance between two screws,rotational speed of screw and gap selection of the TSRE can refer to the design theories of co-rotating twin screw extruder,but the section of thread lead and actual top width of flight,simplifying of the side curve of channel,reverse thread design and structure design of the TSRE need some unique design theories and methods.Finally,the application of design theories and methods mentioned above is explained by an example.