Analysis On Welding Residual Stress With ANSYS

Welding is one most important connection joint in mordern streel structure. Welding is widely used in streel structure. To design and make economical welding steel structure with high performance, we must correctly understand and master the characteristics of the welding structure. Residual stress is induced in the welding process. Residual stress afects the period of construction as well as that of service. It is very important to know how to determine residual stress distribution, especially the residual stress distribution in three-dimensional compoment. As far as the design and construction of steel structure are concerned, determination of residual stress is an important theory guiding and a valuable application reference. In order to get high quality welding structure, these factors have to be controlled, if welding process can be simulated with computer, the best design, procedure method and optimum welding parameter can be obtained.Based on summing on other's experience, this paper systemically discusses the finite element analytical system of the welding process, and sums up the methods of measuring the residual stress. Utilizing the software ANSYS, welding temperatuer field and stress field is researched. The welding process of 3D I beam is simulated, and the results on the different layers and the different welding orders are analyzed.By means of ANSYS' thermal-structure couple function, welding temperature field is calculated firstly and the results are saved in file type of *.rth, and then the temperature results recovered from the former file is added on the structure model as load to simulate the stress and strain field. Welding temperature field and stress, strain field is bidirectional couple, however, the paper only considers the single couple which temperature field effects on stress and strain field as stress and strain field has little influence on temperature field. By simulation of temperature field and stress field in the indirect method, the temperature distributions at different times, residual and strain distribution is gotten, the distributions of welding residual stress along flang girth and web plate are also gotten. The researches show, if weld length is much longer than effective diameter of heat sourse, beam length has almost not influence on residual stress in the middle section of beam; multilayer welding is better than single-layer welding in performance; stitch welding in across corners can effectively reduce the residual stress and deformation to I beam. The research provides reference for the analysis of welding temperature field, stress and deformation in complex welding structure.