某型核电汽轮机凝汽器半侧运行分析

Analysis of the half-side operation of a nuclear power steam turbine condenser

某核电汽轮机凝汽器半侧运行时发生钛管断裂,失效分析判断为流体弹性激振导致的疲劳断裂。从流体激励与管束振动响应出发,研究凝汽器半侧运行时稳态、瞬态激励对钛管振动的影响,发现凝汽器半侧运行如所带负荷偏高叠加危急疏水时容易诱发流体弹性激振。根据该型凝汽器的管束设计特点,对激振敏感区域的钛管进行堵管和加防磨条处理,同时优化了半侧运行时允许的最高汽轮机负荷。此外,凝汽器半侧运行时可能导致汽轮机低压转子与端部汽封的动静摩擦,该问题可以通过磨合处理解决。

Titanium tube fracture occurs during the half-side operation of a nuclear steam turbine condenser,the failure analysis is judged as the fatigue fracture caused by the fluid elastic excitation.Furthermore,from the aspects of fluid excitation and vibration response of the tube bundle,the effects of steady state and transient excitation on the vibration of the titanium tube are studied during the half-side operation of condenser.It is concluded that fluid elastic excitation is easily induced by higher load and emergency drain during the half-side operation of condenser.According to the characteristics of the tube bundle design of the condenser,the titanium tube in the sensitive region of excitation is treated with pipe plugging and adding anti-abrasive strips.And the maximum steam turbine load allowed for half-side operation is optimized.In addition,the half-side operation of the condenser may cause the static and dynamic friction between the turbine low-pressure rotor and the end of the steam seal,which can be solved by running-in.