Diagnostics and testing of rotating electrical machines - DNV Kema

04
ENERGY
Non-destructive testing & plant diagnostics
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Quality control: checking the manufacturing process by
inspection and testing. Various components are tested during
manufacture. The manufacturer’s progress, quality assurance
measures and results are also assessed.
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Tests (FAT and SAT): DNV KEMA performs its own tests or
witnesses testing by others to check conformance to the design
specifications. During factory acceptance testing (FAT), type
tests and routine tests are performed to verify that the rotating
machine has been built in accordance with the specifications.
During site acceptance testing (SAT), the quality of the
delivered installation is checked to ascertain whether it fullfils
the applicable requirements.
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Commissioning: once all the separate components have been
installed and tested, DNV KEMA will witness and assess testing
of the complete installation under various normal and/or
extreme operating scenarios, defined by consultation.
From design to decommissioning
The life cycle of any machine may be divided into the following phases:
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Design
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Manufacture
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Operation
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Conservation
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Decommissioning
Operations
Our approach to condition assessment and residual service life
forecasting has several elements, which together provide an
accurate picture of the machine as a whole. First there is the
actual inspection and testing. These activities are followed by
the interpretation of measured data and analysis of the existing
situation. Interpretation and analysis yield an overview of the
condition of the machine and its likely residual service life.
Finally, there is failure analysis. In the event of unexpected
problems, destructive testing of the failed component can be
undertaken to ascertain the cause. As well as providing you
with insight into the condition and residual service life of your
machinery, we can advise you regarding the most cost-effective
repair, maintenance and operating strategy. We can indicate
whether it is best to take a machine out of service straight away,
to make provision for replacement, or to continue running the
machine normally. The diagnostic techniques that we use are
selected to minimize the need to dismantle rotating machinery.
Dismantling is a costly and time-consuming business, which
introduces risk; as such it should be avoided except where
strictly necessary.
DNV KEMA uses four primary techniques for condition
assessment and residual service life forecasting:
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Endoscopy: a visual inspection technique that enables the
examination of areas that cannot be viewed with the naked eye
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Dielectric testing: a technique for assessing the electrical
insulation of rotating machinery components