Vibration fault analysis and treatment of 600 MW double-stage movable vane adjustable induced draft fan
LI Song-bo
Abstract：The horizontal,vertical and axial vibration of the motor and fan of a 600MW double-stage moving-blade adjustable induced draft fan are larger after the combination of induction and augmentation.The main reason is that the design output of the motor itself does not match and the magnetic center line deviation of the motor is large,resulting in large vibration.After replacing the motor and carrying out the balance test,the vibration of the motor and the fan is reduced.In the subsequent long-term operation process,the vibration increased frequently.After tracking analysis and processing,it is found that because the original foundation and air duct are used after the transformation,the design critical speed of shafting is close to the working speed and causes resonance,which leads to cracks in the bearing box support,poor alignment and excessively large blade passing frequency.By shortening the length of the intermediate shaft by 200 mm,adjusting the center in time,and combining with the balancing test on the impeller of the fan,the fault of large vibration can be solved.
Keywords：induced draft fandynamic balancebearing box support crackmisalignmentblade passage frequencyvibration fault
Publication Date：2024-12-15
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 75-78 )