[Purposes]In order to improve the reliability of fans,solve the problem of abnormal noise dur-ing operation,optimize the assembly process of fan bearings,reduce the impact of fan imbalance and mis-alignment faults,and improve the reliability of the fan,this paper conducts failure analysis on axial flow fan bearings.[Methods]This article takes the axial flow fan bearings used in cooling towers as the re-search object,investigates and analyzes the assembly process and performance of similar bearings under similar working conditions.Precision instruments such as roughness measuring instruments and tensile testing machines are used to measure the diameter,surface roughness,speed,fan noise,material compo-sition,and tensile strength of the transmission shaft that matches the bearings.The reasons for bearing failure in long-term service fans are analyzed and studied.[Findings]The results indicate the vital im-portance of the bearing's locating pin for its service life during prolonged,high-speed rotation of the fan.In the absence of the locating pin in the bearing seat,the fastening screws tend to loosen,disrupting the original dynamic balance system and subjecting the bearing to additional axial and radial loads,resulting in increased local stress,heat generation,and axial slippage,leading to localized damage and plastic de-formation of the shaft.Conversely,fan bearings equipped with locating pins exhibit a securely fastened screw state,intact dynamic balance system,and optimal operational conditions.After bearing failure,there is a certain ellipticity in the local shaft diameter,reduced surface roughness in bright spots,signifi-cant changes in noise accompanied by unusual sounds.[Conclusions]The material composition and strength of the drive shaft meet the usage requirements,and operational conditions influence its reliabil-ity.By adding locating pins to the bearing seat,it is possible to effectively enhance the service life of fan bearings.Regular inspection of the position of bearing fastening screws,as well as monitoring fan noise,can reduce the downtime of cooling tower fans,decrease maintenance costs,and improve service life.
万方数据
维普
