Influence Infector Analysis On Field Dynamic Balancing Accuracy For Rotor System

Practice has proved that imbalance is one of the main reasons of abnormal vibrationon rotating machinery. Relative to the operation on additional balancing machine, fielddynamic balancing conducts correction in actual operating condition，which can improvethe final running condition of the mechanical equipment effectively，has been increasinglyaccepted and applied in equipment maintenance. But with the complexity of operatingenvironments and the diversity of mechanical structures, many interference factors maylead to the instability or failure of balancing. Therefore, influence facotrs in each link offield dynamic balancing should be analyzed to ensure the high balancing accuracy and gainthe good running condition. Firstly, signal test as the basic step of field dynamic balancingis studied in this paper. To avoid the errors caused by phase measurement and unstablevibration, measuirng system should be arranged independently and the signal must bepreprocessed before calculation. Secondly, the installation errors of correct and balancemass along the rotor radial plane and axial line are analyzed to acquire the basic pirncipleswhich can reduce the errors in field. At the same time，the lag angle in phase calculation oftest mass on specific rotating equipment is given. Thirdly，inlfuence coefifcients areconnected with the mode shape function, which provides the condition to analysis thephenomenon of unbalance vibration in dynamics range and proves the relationshipbetween positions of balancing plane and ill-conditioned equation. And the law of axiallocations that usually occurs ill-conditioned equation under different working conditionsare gained to guide the practice operation. Finally, based on rotor dynamics model, thepaper analyzes vibration characteirstics of rotor system with significantly anisotropicstififiess structure and points out that traditional one-way sensor measurement can notcompletely describe imbalance information in this kind of rotor imbalance. Two-way RMSimprove balance method is proposed on the basis of average balance method, whichmerges mean filtering algorithm with root mean square algorithm to deal with the datacollected by two mutually perpendicular sensors. Balancing experimental results shows that the new method is simple and easy to operate and can effectively improve theaccuracy of dynamic balance.