The Failure Analysis And Numerical Simulation Of The Screw Transmissiong Shaft

Screw extruder has been used in the improvement of engineering plastics,granulation,pre-mixing and other production process.As its core components,Screw shaft,its dedendum tends to form a large stress concentration because of the discontinuity of geometric structure.Along with the manufacturing process,material corrosion,poor management and a series of problems,shaft fracture often.Therefore,It `s meaningful to the safe operation of the equipment that the failure analysis and numerical simulation of the broken screw shaftAs an important structure of the pipeline to change direction and material flow,tee is widely used in power plants,petrochemical and other industrial production.However,due to discontinuity ofgeometric structure’s change of tee,serious stress concentration frequently occurs at the intersection line.And due to the manufacturing process,materials,corrosion,imperfect in management and other reasons,the tee often contains defects such as porosity and crack,which makes tee more easily damaged in the container and pipeline.Therefore,the failure analysis of the three links is of great significance to the long period safe operation of the equipment.In this paper,based on the engineering practice of the screw extruder screw shaft fracture failure as the background.The macro-microcosmic morphology of screw shaft fracture surface,metallographic examination of fracture surface and energy spectrum analysis of fracture surface was applied to the failure analysis.The causes of failure of the screw shaft are analyzed and the corresponding preventive measures are put forward.In this paper,the fracture of the screw shaft is simulated and analyzed,Using the finite element analysis software ANSYS to establish the finite element model which is in accordance with the actual size.The stress analysis of the whole screw shaft was carried out,and the displacement vector image and the Von Mises stress nephogram of the screw shaft under the working condition were obtained.There is a large stress concentration at the tooth root.In order to further investigate the stress and bearing capacity of the screw shaft with the actual crack,According to the basic principle of fracture mechanics,the stress analysis of the screw shaft fracture model with crack is carried out,and the stress intensity factor at the crack tip is calculated.