蒸汽发生器传热管与管板焊缝应力和疲劳分析

Stress and Fatigue Analysis of the Tube-to-Tube Sheet Weld in Steam Generator

蒸汽发生器是压水堆核电厂的关键设备之一,其中的传热管与管板一般采用胀管加焊接的方式保证密封性。传热管与管板之间的焊缝的几何尺寸小,应力情况复杂,同时该位置极易发生泄漏,因此该焊缝的应力分析与评价是核电厂安全的重要基础。文中采用有限元方法对传热管和管板焊缝进行了应力分析,分析中采用了多孔板等效、刚度等效和孔边环向应力等效等多种方法,简化了模型的复杂度,计算得到了各种工况下的应力情况,并按照ASME规范对其进行了评定。

Steam generator is one of the key equipments in the pressurized water reactor nuclear power station. The hydraulic expansion method and welding method are used orderly to ensure the seal between tube and tube sheet. The weht with small scale and complex stress is easy to leak, so that the stress analysis and evaluation are very important groundwork for the security of the nuclear power station. In this paper the finite element method （FEM） is used to analyze the stress of tube to tube sheet weld. The perforated plate equivalent, the stiffness equivalent and the hoop stress equivalent methods are used to simplify the model. The stress conditions in different load cases are calculated and evaluated based on the rules of ASME code.