Study And Design On Screw Parameters Of Twin Screw Pupling Extruder Based On Similaer Theory

Twin screw pulping extruder is a new type of energy-efficient pulping machine, which have a good characteristic and broad future. Now the design theories flow rate, power consumption and the axis force of twin screw pulping extruder are in the initial stages of study, there is no mature theoretical results, theoretical calculation and known conditions are complex. That restricts the design and use of this new equipment, so it is very important to study further on the theory of twin screw pulping extruder.The paper focuses on describing similar theory, summarizes application of similarity theory in the mechanical at home and abroad, which includes basic rule and method of similarity theory in engineering especially in the screw engineering. The paper analyses similar between twin screw pulping extruder and twin screw extruder, in order to use the design theory of twin screw extruder.According to the principle of geometric similarity, the paper realizes parametric design of the screw through UG and C++. Some important components are controlled by separately. It improves the design efficiency, avoids repetitive works and reduces development period.Based on non-dimensional method, the paper derivates the similarity criterion among flow rate, power consumption, speed, diameter, pressure and axis force. For demonstrating accuracy of criterion, the paper compares experimental results and theoretical value, which includes values of theoretical equation of power and axis force according to its extrusion model, and equation of geometry flow rate, through experiment. The deviation existing between experiment results and individual value after contrast with the theoretical curve, the trend in total is consistent with the theoretical trend.The paper studies further in depth on appliance of similarity theory on twin screw pulping extruder. The similarity criterion of flow rate, power and axis force based on non-dimension method provides a reliable basis for estimating main parameters of twin screw pulping extruder, selecting screw bearing of twin screw pulping extruder and electrical motor, so it has vital significance for the design of twin screw pulping extruder.