摘要
某给水泵汽轮机正式投运后一段时间内,压力级第2级动叶片多次发生裂纹萌生及断裂失效的故障。通过对现场运行状态的调查及对断口形貌的仔细分析,发现蒸汽品质欠佳,叶片失效模式为典型的高周疲劳断裂。针对现场复杂的运行状态,在蒸汽品质难以短期改善的情况下,对叶片结构进行了局部优化,将叶片型线由原来的直叶片改为扭叶片,以减少冲角带来的不稳定汽流影响,同时将叶片由原来的整体围带结构改为了整圈自锁结构,以提升叶片的抗振能力,并且还对叶根型线进行了优化。采用上述优化措施后,叶片失效问题得以解决。研究成果可为类似叶片失效问题的处理提供借鉴。
During formal operation of a boiler feed pump turbine,some rotating blades in the 2nd stage have experienced repeated crack initiation and fracture failure.Through investigation of the onsite operation state and analysis on the fracture morphology,it was found that the steam quality was not good,and the failure mode of the blades was typical high cycle fatigue fracture.Considering the complex operating conditions onsite and the difficulty to improve the steam quality in short term,the blade structure was locally optimized.The blades were changed from original straight profile to twisted profile so as to reduce the influence of unsteady steam flow caused by the attack angle.Meanwhile,the original integral shroud structure of the blades was replaced by interlocked structure,so the anti⁃vibration ability of the blades was improved.Optimization was also carried out for the root profile of blades.After the above measures being taken,the blade failure problem was solved.The research results can provide reference for the treatment of similar problems of blade failure.
作者
李文福
LI Wenfu(Shanghai Turbine Works Co.,Ltd.,Shanghai 200240,China)
出处
《热力透平》
2024年第4期270-275,共6页
Thermal Turbine
关键词
汽轮机
叶片失效
整圈自锁
型线优化
steam turbine
blade failure
interlocked
profile optimization
