内压对锥柱耐压壳焊接残余应力影响的数值模拟与试验研究

Simulation and experimental of internal pressure influence on welding residual stresses of cone-cylinder pressure hull

耐压结构在使用前一般都要进行内压试验,经过内压试验后结构的焊接残余应力会发生改变。残余应力的变化会对结构的力学特性有一定影响。文章首先运用ANSYS的APDL语言编写了大尺度锥柱耐压壳模型焊接残余应力数值模拟程序,对耐压结构的初始残余应力和经过内压试验后残余应力的变化进行计算;然后,采用X射线无损检测方法对该大尺度锥柱耐压壳模型的初始残余应力和经过内压试验后的残余应力进行测量。计算结果与试验结果表明,随着内压增加,内壳残余拉应力不断降低;而外壳残余压应力则变化不大;并且数值模拟结果与试验结果基本吻合。该文研究结果为更加合理可靠地进行耐压结构力学特性分析提供了理论依据。

There is generally internal pressure tests for pressure structure before its service, and the residual stresses could be changed after the internal pressure tests. The mechanical property would be affected by the variation of the residual stresses. In this paper, a program of the simulation of the welding residual stresses for a large scale model of cone-cylinder pressure hull is done with APDL of ANSYS firstly, and the initial residual stresses and the variation of residual stresses after tests are calculated; Then, the initial residual stresses and the residual stresses after the internal pressure tests are measured with X-ray nondestructive detection for the large scale model of cone-cylindrical pressure hull. The results of calculation and the test show that the residual tensile stresses decrease constantly on the internal surface with the increase of the internal pressure, and the residual compress stresses change little on outer surface; The numerical simulation results are coincident with the test results. The research provides a more over theoretical basis for the mechanical characteristics analysis of pressure structure.