锥柱耐压壳高强度钢典型焊接接头残余应力研究

摘要

Cone-cylinder pressure hull is often built with high strength steel which is sensitive to the residual stress. Therefore, it is necessary to research the residual stress of the typical welded joint of the cone-cylinder pressure hull. A numerical simulation program of the welding residual stress with Ansys APDL language which based on thermal elastic-plastic theory was carried out in this paper. The influences of the thickness, the width, the cone angle, the welding speed and the welding throat temperature on the axial welding residual tress of the welded joint have been studied. The research results show that the residual tensile stress is larger near the weld toes of the concave of the cone-cylinder pressure hull. So it is necessary to define this area as the key area for research of the fatigue strength. The thickness and the cone angle have larger influences on the residual tensile stress than that of on the residual compressive stress. The width and the welding throat temperature have large influences on both the residual tensile stress and the residual compressive stress. So it is advantages for control of the residual stress and optimization of welding process technology. Moreover, the related theoretical basis of the fatigue strength of the pressure structure is also established.%锥柱耐压壳常采用高强度钢建造，高强度钢对焊接残余应力较为敏感，因此有必要针对耐压结构典型焊接接头的残余应力进行研究。本文基于热弹塑性相关理论，采用Ansys的APDL语言编制焊接残余应力数值模拟程序。研究板厚、板宽、锥角以及焊接速度、焊喉温度对典型焊接接头轴向焊接残余应力的影响。研究表明：锥柱耐压壳凹面焊趾附近区域残余拉应力较大，应作为疲劳强度研究的重点区域。板厚和焊喉温度对残余拉应力的影响较残余压应力大；板宽和锥角对残余拉、压应力影响均较大。本文的研究可以控制焊接残余应力和优化焊接加工工艺，并为后续耐压结构疲劳强度的研究奠定相关理论基础。