东方660 MW超超临界二次再热汽轮机超高压主汽阀阀杆动应力分析

摘要

汽轮机主汽阀需要很高的关闭速度，由此带来阀杆冲击动力学的强度问题。以前设计主要按照冲击动力学的理论，通过能量法求解系统动应力。文章介绍了阀杆动应力的理论计算方法，并分析了理论计算方法的合理性。随着计算机技术的发展，有限元方法求解阀杆动应力成为可能。文章详细介绍了阀杆动应力有限元计算参数的选取方法，并通过ABAQUS商用有限元软件计算了东方660 MW超超临界二次再热汽轮机超高压主汽阀阀杆动应力。对理论计算结果和有限元计算结果做了比较，分析了有限元计算结果的合理性。计算显示东方660 MW超超临界二次再热汽轮机超高压主汽阀阀杆峰值应力小于材料疲劳极限，阀杆具有永久寿命。%The main steam valve has to shut quickly, which usually leads to large impact dynamic stress. In the past, it always uses en⁃ergy method to slove system dynamic stress. This paper introduces the energy method and analyzes rationality of energy method. With the development of computer, using FEM method to slove the dynamic stress of the valve rod is possible now. This paper presents the method to determine the calculation parameter of FEM method and uses ABAQUS to calcualate the dynamic stress for main steam valve rod of Dongfang ultra-supercritical double-reheat 660 MW steam turbine. It also compares the energy and the FEM method re⁃sult, and analyzes the rationality of the FEM result. The result shows that the dynamic stress of the valve rod is less than the fatigue lim⁃it of the material, the rod has unlimited life.