一些汽轮机的叶轮采用红套过盈结构。为了防止过盈失效,在结构上还加了一个轴向键,以防止叶轮和轴产生错位。前些年国内一台中压汽轮机在第五次大修后,进行危 急遮断器超速跳闸试验时,第十级(末级)叶轮在设有任何预兆的情况下突然飞裂,造成一次重大设备事故。图1就是飞裂叶轮的残体实物照片。 Some turbine impeller using red over-interference structure. In order to prevent interference failure, the structure also added an axial key to prevent the impeller and shaft misalignment. In the previous years, after a fifth overhaul, a medium-pressure turbine in China carried out an emergency breaker overspeed tripping test. When the tenth stage (last stage) impeller suddenly broke with any sign, it caused a major equipment accident. Figure 1 is the fissure impeller debris physical photos.