“O”形圈液压胀杆受力及断裂分析研究

Study on Stress and Fracture Analysis of “O” Shaped Hydraulic Expansion Rod

核电蒸汽发生器管子管板接头普遍采用胀接和焊接结合的连接方法。管子管板的胀接,能够消除换热器管子和管板间的初始间隙,提高管子管板接头耐压、耐高温和抵御载荷波动的能力,降低应力腐蚀和疲劳破坏的风险。本文结合公司某在制项目液压胀时胀杆偶然断裂事故,探讨"O"形圈液压胀杆胀接原理,在反复加载工作环境下,对胀杆胀接时拉伸载荷、弯曲载荷进行理论计算,并对此断裂断口形貌进行金相分析,提出预防此类事故的措施,为后续项目提供经验反馈和借鉴。

The joint method of expansion and welding is widely used in pipe, tube and plate joint of nuclear steam generator. Tube to tubesheet expanding, can eliminate the heat exchanger tube and the initial gap between the tube plate, improve the ability of tube to tubesheet joints of high temperature and pressure, resist the load fluctuation, reduce the risk of stress corrosion and fatigue damage. In this paper, combined with the company in a project of hydraulic expansion when the expansion rod is broken by accident accidents, discusses the ＂O＂ ring of hydraulic expansion rod expansion principle, in the repeated loading work environment to calculate the expanding rod expansion when the tensile load, bending load, and the fracture morphology of metallographic analysis, put forward to prevent such measures of accident, provides experience feedback and reference for the follow-up project.