汽轮机主汽门内部裂纹产生原因分析与处理

神华国能神东电力有限责任公司萨拉齐电厂1号机组主汽门内部内肋板与阀体焊接处焊缝出现裂纹,分析认为主汽门出厂时热处理不彻底、内肋板焊缝存有残余应力、机组运行中热应力的交叠作用等是裂纹产生的主要原因。通过采取切除内肋板、对主汽门内壁裂纹进行打磨并圆滑过渡等现场处理措施,及时修复了1号机组主汽门。

Cause Analysis and Treatment of Internal Crack in Steam Turbine Main Valve

Took Salaqi Power Plant No.1 unit as an example, this paper analized the causes of the cracks within the main steam valve, thought that heat treatment was not thoroughgoing, the internal ribbed plate weld had residual stress, and the unit thermal stress were the main reasons for the crack. By cutting the internal ribbed plate,burnishing and smoothing the wall crack in the main steam valve, timely repaired the main valve of No.1 unit.