论文部分内容阅读
前言霍县发电厂2号机第廿八级叶轮进汽侧轮缘处发生了开裂,对其开裂小块进行了全面的宏观、断口、显微组织、分支裂纹走向及显微硬度测定等试验。试验结果认为,该叶轮轮缘处的局部开裂属于应力腐蚀开裂。在对应力、介质条件及材料敏感性等进行综合分析后认为,在引起应力腐蚀开裂的诸因素中,因叶轮与隔板间发生严重磨损所产生的附加应力(包括热应力和组织应力),乃是造成该级叶轮轮缘应力腐蚀开裂的主要因素。
Preface Huoxian Power Plant No. 2 machine twenty-eighth impeller inlet side of the rims occurred at the crack, the cracking of small pieces carried out a comprehensive macro, fracture, microstructure, branch crack direction and the determination of microhardness test . The test results show that the local cracking at the impeller rim belongs to stress corrosion cracking. After a comprehensive analysis of stress, medium conditions and material sensitivities, it is considered that among the factors causing stress corrosion cracking, additional stress (including thermal stress and tissue stress) caused by severe wear between the impeller and the separator, But it is the main factor that caused the stress corrosion cracking of the impeller wheel flange.