Prediction And Control Of Welding Deformation Of Five-Port Connector Based On FEA

The welding structure is widely used in the industry of spaceflight, bridge, pressure vessel etc. The residual stress always inevitably remains and the welding deformation is always formed during the heating and cooling of welding process. The traditional method TIG, which is used to weld the five-port connector of rocket and flange, will suffer the problems like unfitness of butt joint and change of gaps. So the TIG method is lacking of stability for welding a qualified product and can not meet the need of the development of the new generation of spaceflight product. This paper which was based on the nonlinearity finite element method technology used ANSYS to simulate the temperature field and stress field produced during the welding process, and analysed the distribution of temperature field and the characteristic of the deformation. This paper firstly introduced the fundamentals of Thermal transfer and Thermo- elastic-plastic theory. The type of welding heat model and other important factors which will have impact on the results of temperature field and welding deformation were also studied.Based on the nonlinearity finite element technology, this paper used ANSYS to build the model of the five-port connector and flange, introduced the 3-D moving Gauss heat model, made ADPL programming to simulate the dynamic welding process. Based on the results of the temperature field, this paper analysed the Thermo- elastic-plastic stress and the welding deformation. The results showed that the area near the welding line remained residual pull stress, which made the flange deform axially and made the bottom of the connector deform inward.