Abstract: In the paper, the effect of the die orifice dimension on output and working pressure is analyzed. Through the experiments, the effect of the die orifice dimension on the output, power consumption and the effect of L/D ration on pressure and expansion rate as well as a degree were led to a conclusion. When the pressure was 5. 5 MPa,L/D=4,the expansion rate reached the maximum) while the pressure was 5. 6 MPa,L/D=4. 1 ,the product a degree arrived at the top value. Based on the experimental data, flow characteristic index and viscosity index of the material passing the die orifice were evaluated. On the basis of the evaluated data, the productivity and pressure drop were calculated.