Viewing Operational Deflection Shapes (ODS) from a Gas Turbine Generator

As its name suggests Operational Deflection Shape analysis shows the vibration pattern experienced during normal operational condition. This is different to other structural vibration tests such as impact hammer tests, bump tests or shaker tests which require a more controlled excitation force and are used to determine specific characteristics of the structure under test, such as natural or resonant frequencies.

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Sampling and Filtering Data for ISO8041 Compliance and Human Body Vibration Data Weighting

Various human body vibration measurements and assessments are defined in the ISO2631, ISO5349, ISO6954 standards and also in the EEC vibration directive 2002/44/EC. These assessments are based on the analysis…

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Bearing & Gearbox Vibration Analysis using Demodulation Techniques? (Part 2)

In our previous post on this subject we briefly looked at how we can use the detailed design information of bearings and gearboxes to look for specific fault conditions by collecting vibration information and analysing their frequency spectra. Amplitude modulation of the vibration signatures is common and we have seen how this causes side-bands to be present in the frequency domain.

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Continue ReadingBearing & Gearbox Vibration Analysis using Demodulation Techniques? (Part 2)