World Pipelines - February 2016 - page 49

I’m pickin’ up
Neil Parkinson, AVT Reliability,
UK, relays the use and benefits of
operating deflection shape analysis.
S ustained, excessive vibration in many key structures, including machinery, tools, pipes and support systems,
can have catastrophic results. If left uncorrected, such vibration can cause failure of the unit and, as a direct
result, huge losses in terms of productivity/downtime and unplanned maintenance or replacement costs.
Even before the unit fails, excessive vibration can greatly reduce the reliability of machinery and generate
environmental hazards – it may also render the machinery (and thus the company or organisation that operates it) non-
compliant with legal and regulatory requirements, for example by causing a hazard to employees’ health and safety.
For complex systems with many degrees of freedom and with potentially multiple mode shapes and frequencies, it
can often be very difficult for the structural vibration analyst to fully understand the nature of the vibration, making it
very difficult to determine the optimum corrective actions.
To assist in the interpretation of such complex vibration problems, one of the most powerful tools available to the
specialist is a measurement-based technique, which enables the actual in-service vibration modes to be individually
visualised and animated. The technique is known as operating deflection shape (ODS) analysis.
bad vibrations
bad vibrationsbad vibrations bad vibrationsbad vibrationsbad vibrations bad vibrationsbad vibrationsbad vibrations bad vibrationsbad vibrationsbad vibrations bad vibrationsbad vibrationsbad v brations bad vibrationsad vibrations
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