Rotor Misalignment Fault Identification Technology

Large-scale rotating machinery is important power equipment in an important pillar industry of national economy. Drive components and be drived components are connected by various types of coupling to the transfer torque. Therefore, during operation, the failure of the coupling often fail, one of the most common fault was undoubtedly the misalignment fault. In a variety of couplings, gear coupling is the most widely used, because it not only simple to manufacture and has the ability to compensate and transmit large torque.This paper analysis the features of the mechanism of the gear coupling misalignment fault, established a mathematical model of the rotor-coupling-bearing system and proposed a new method for a quantitative analysis of the misalignment fault.At first, misalignment fault mechanism and characteristics of gear coupling were analyzed, Mathematical expressions of exciting force which coupling shell applied to the coupling halves is got; Mathematical expressions of radial force which teeth applied to the rotor system by studying teeth meshing, also get the relationship between misalignment volume and radial force.Established mathematical model of misalignment force and oil film force which bearing applied to the rotor system, thus established differential equations of motion of the rotor system.Rotor displacement, velocity and acceleration of every node are solved by Newmark-β. With the speed of change, the effect of the motion characteristics of the coupling is studied. The entire rotor system vibration characteristics are also studied because of the presence of misaligned coupling.The methods of traditional misalignment diagnosis is qualitative analysis.This paper propose the quantitative analysis. Simulation the vibration characteristics of the key positions of the rotor system verify its correctness.