Finally, let's touch on the topic of the dynamic eccentricity of the electric motor rotor. The defect is relatively rare and interesting. As usual, from my own practice, therefore, further there will be spectra, the search for the cause, and of course photographs.

As part of a seismic analysis for a 1000 horsepower vertical 14 pole induction pump motor the reed frequency was calculated using a finite element analysis (FEA) program. This paper will discuss the FEA modeling for the seismic analysis and natural frequency determination. The calculations were done for the
motor only on a rigid support. After the motor completed the standard factory tests, an impact test was conducted in the rigid mount condition to determine the structural natural frequencies. The tested values will be compared to the calculated values from the FEA model. This paper will also discuss the subsequent motor/pump system resonance problems that surfaced after the motor/pump was installed on site. This paper will highlight the importance of the system integrators design of the motor support structure to avoid structural resonance problems such as in this case.

Recently we faced an interesting problem - identical bearing defects were found on four identical centrifugal pumps for four months.

For another real example, I propose to consider vibration diagnostics of fan bearings. Let's disassemble the bearings and make sure that inspection is a key step in determining the root cause of the failure.

Equipment repair is a must. A diagnostic specialist has to assess the technical condition of the equipment, and, accordingly, the quality of the repair. But it so happened that I expect the withdrawal of the unit from repair at my enterprise with some shudder.

Every day we are used to facing the same problems on the pumps. Sometimes one glance at the vibration spectrum is enough to identify the problem and issue recommendations for its elimination. But sometimes the diagnostician is given the opportunity to work hard. In this article, we will consider a practical case of vibration diagnostics of vertical pumps, conduct a whole study and identify an incomprehensible spectral component.

Bending of the pump shaft is rare. It can be determined by means of vibration diagnostics, and in some cases by simple inspection. In this article, we will consider a practical case of detecting this defect visually.

Vibration diagnostics can not always accurately indicate the root cause of the poor technical condition of the equipment. There are various defects that can occur at the same frequencies. Therefore, before doing a more in-depth analysis, Victor Wowk, based on his experience, suggests using simple tools and methods to check the five conditions that will help identify the most common equipment problems. It is recommended that you keep this knowledge in your arsenal and apply it to novice mechanical engineers.

I received an application for vibration diagnostics of an electric motor of type 5AN355 V4 U3 (400 kW, 1480 rpm) after a major overhaul. This electric motor works in tandem with the mains pump at the boiler house in Reutov.