An integrated study for solving high vibration problem of a deep well turbine pump

Abstract

Mechanical vibrations are a common problem encountered in many machines, especially for vertical turbine pumps. These pumps are generally difficult to stiffen or damp, but the effective diagnosis must begin with an understanding of the underlying vibratory sources. In the present work, a deep well vertical turbine pump experienced extremely high vibrations for a long time although it still being new. It hasn't been in operation for over 6 months. The pump system suffers from extremely high vibration levels relative to the rotational speed (1X motor dominant frequency). An efficient strategy was implemented by using well-conceived techniques. The experimental modal analysis confirmed a presence of a natural frequency. Modifications were carried out to overcome resonance. Finite element analysis was done to determine the reed critical frequencies as a powerful tool to identify and mitigate vibration issues. On-site motor balancing was done to remove vibrations due to the residual imbalance. Results revealed decreasing vibration level by about 66% after solving all problems.

Keywords

• finite element analysis
• resonance
• modal analysis
• vibration analysis
• vertical turbine pump