高中压汽门阀座裂纹产生原因及处理方案

Causes and Solutions of Valve Seat Cracks in High and Middle Pressure Valves

现场检修过程中,发现1 000 MW超超临界汽轮机高中压阀组阀座密封焊缝存在"家族性"开裂现象,分析了阀座裂纹产生的原因;考虑到阀门所处恶劣工况及阀门的重要性,采用自动钨极氩弧焊方式堆焊处理。修复后,主设备及机组长期安全稳定运行。

During on-site maintenance,"familial" cracking in the valve seat seal weld of 1 000 MW ultra-supercritical steam turbine high and medium pressure valve group is found.It analyzes the cause of valve seat cracks.Considering the bad working conditions and the importance of the valve,automatic argon tungsten-arc welding is adopted for surfacing treatment.After the treatment,the main equipment and unit has a long-term safe and stable operation.