轴流式通风机叶轮疲劳断裂的故障分析及对策

Fault analysis and countermeasure for fatigue fracture of axial fan impeller

某工程项目中2台相同规格的轴流式通风机在运行一年后先后发生相同故障,通风机叶轮均有一个叶片断裂。经分析,认为通风机喘振导致叶片产生的交变载荷是通风机叶片断裂的根本原因。为确保通风机可靠运行,对通风机叶轮进行优化设计,提高叶轮抗轴向交变载荷的能力,并对风道进行改进,降低通风机振动。结果显示,改进后通风机振动值最高不超过3 mm/s,证明对轴流式通风机叶轮疲劳断裂的故障分析的正确性及改进措施的可行性。

In one engineering project,the same fault occurred in two axial fans with the same specification successively after running for one year,which are both blade fracture among the impellers.After analysis,it’s considered that the alternating load from the blades caused by fan surge is the basic reason of fracture of fan blade.In order to ensure the reliable operation of fan,the optimization design is conducted on the fan impeller to improve ability to resist alternating load,and the system duct is improved to reduce the fan vibration.The results show that after improvement,the maximum value of fan vibration is not higher than 3 mm/s,which verifies the correction of the fault analysis on fatigue fracture and the feasibility of improvement measures.