某电厂水冷壁管在使用过程中发生爆裂泄漏, 在水冷壁管爆裂区域及附近取样, 通过宏观检验、化学成分分析、拉伸试验、硬度试验、金相检验、能谱分析的手段分析了其爆裂原因。结果表明: 工作过程中水冷壁管迎火面温度较高, 在超温状态下, 氧化膜易发生破裂; 上游凝汽器泄漏带来的铜及其氧化物在水冷壁管的流体稳定区域发生沉积, 形成垢下腐蚀环境; 在多种腐蚀因素的共同作用下, 材料发生了氢腐蚀, 并最终导致爆裂。最后根据爆裂原因提出了预防措施。

The water wall tube in a power plant burst and leaked during service. The water wall tube was sampled in the bursting area and its distinct, and the bursting reasons were analyzed by means of macrographic examination, chemical composition analysis, tensile test, hardness test, metallographic examination and energy spectrum analysis. The results show that: the temperature of the water wall tube exposed to the fire was comparably high during service, and the oxidation film was easy to fracture under overheat condition; copper and its oxidation from the condenser deposited in the fluid stable region of the water wall tube, forming the under-deposit corrosive environment; under the combined action of various corrosion factors, hydrogen-type corrosion happened to the material and eventually led to the bursting. Finally according to bursting reasons, prevention measures were put forward.