MEASUREMENT OF WELDING RESIDUAL STRESS IN THE HEAVY CONVERTER USING BLIND-HOAL METHORD
基于大型炉体焊接残余应力测试的盲孔法研究

To enhance the measurement accuracy for welding residual stress in the converter,the traditional blind-hole method is improved by widening hole and increasing depth more than once after drilling hole on one measuring point.Strain relief parameters A and B for welding residual stress of Steel SM400ZL measured by the blind-hole method are verified by test,applying multi-group strain relief parameters for calculation.Welding residual stress estimations in different conditions are obtained,and compared with test results.In the force tensile test,it is found that the plastic deformation around the blind hole influences the measurement precision and plastic correction formulation.The tests show that the improved blind-hole method could measure the residual stress more accurately,and by plastic correction the largest measurement error is reduced with in 2%. The test method and results can be directly used in welding residual stress measurement of Steel SM400ZL.