近年我国大型汽轮机末级长叶片的冲蚀损伤

Erosion Damage on the Last Stage Blades of Large Capacity Steam Turbine in China Recently

汽轮机末级叶片在极繁重的条件下工作 ,其安全可靠性备受关注。该文在深入调查大机组末级长叶片运行情况的基础上 ,简要介绍了末级长叶片冲蚀损伤的机理及其严重危害性 ,着重指出近几年随着新出现的大机组长期带低负荷参与调峰运行 ,相当普遍地发生了末级长叶片出汽侧的冲蚀损伤 ;在北方地区某些机组上叶片进汽侧也发生大范围 (在叶顶防蚀区以下 )的冲蚀损伤。提出了相应的防范措施以及大机组调峰运行应综合考虑末级叶片的强度和寿命的观点。图 2参

Last stage blades of steam turbines operated in the very heavy conditions, so their safety and reliability are very concerned. This article briefly introduces the mechanisms and harmfulness of erosion damage on the blades based on the investigations of their operation conditions. It emphasized that erosion damage quite commonly occurred in the trailing side of the blades as the large capacity turbines operated at the conditions of low load and peaking load in the long term. It shows that erosion damage also occurred in the large zone of leading side (below the erosion prevention part of the tip) for the turbines in North of China. Finally this paper presented corresponding prevention measures, and gives the point that it is necessary to comprehensively consider the strength and life of the last stage blades in the operatioin condition of peaking load. Figs 2 and ref 1.