Abstract: Digital simulation of contacting process between the teeth was performed and the stress analysis of stream setting vessel was made by elastic finite element method.The researchers evaluated the fatigue life and stress intensity of the dangerous cross-section.Considering the yielding possibility of the teeth,the elastic-plasticity finite element analysis of the model was conducted and compared with the elastic solution.The results of the two methods are very similar,and both of which show that the contact pressure reduces progressively from both edges of the tooth to the middle and distributes along the radial direction like a parabola.The max stress appears at the root of top flange teeth.This demonstrates that the solution that is computed based upon the elastic assumption is reasonable.A lot of engineering experiences have proved that this kind of machines analyzed by elastic contact element method can meet the requirements on structure strength and fatigue life.