Reference Information
Key information from reference documents and guides (e.g.) or succinct descriptions of concepts (e.g. what is risk and how do I visualize it)
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Key information from reference documents and guides (e.g.) or succinct descriptions of concepts (e.g. what is risk and how do I visualize it)
New Life Cycle Decision Tools for Asset Managers, Engineers and Maintenance Personnel
Screening a service territory for “at risk” substations and transmission line structures requires knowledge of the environmental factors and how those factors impact the structural integrity. That potential damage is categorized by severity and visualized by colors in the steel, zinc and copper soil corrosivity maps and models.
GPS coordinates for Substations or Transmission line circuits may be cross referenced to the soil corrosivity maps to determine the corrosion rate severity for that asset. This empirical data allows a utility to choose between various preventative or corrective maintenance philosophies and optimize their O&M budgets by modeling their asset condition.
EPRI soil corrosivity maps have been developed by characterizing soils in the laboratory which are then validated by health assessments in a field survey. This practice provides utilities the confidence that their asset management models are accurate due to a high confidence level and a low margin of error.
Technical Notes:
Corrosion Behavior of Sub-Grade Mechanical Fasteners Most mechanical fasteners contain multiple alloys and each metal alloy corrodes at a different rate causing a loss of structural integrity. Laboratory evaluation of each fastener allows an understanding of the impact of different stresses but also how that fastener will fail in service. Utilities may then use this knowledge for fastener selection but also to determine inspection cycles for the substation grounds.
Cathodic Protection and the Effects of Stray Current In many cases the voltage level of stray currents that are found within the ROW fall below the safety criteria for touch and step potentials, so it is ignored and the effects are not well understood. This can be a fatal flaw in the asset management processes and discharge current may severely reduce the service life of a structure. This video demonstrates the concepts of anodic and cathodic interference and how we may identify each source to mitigate the stray current interference.
Most mechanical fasteners contain multiple alloys and each metal alloy corrodes at a different rate causing a loss of structural integrity. Laboratory evaluation of each fastener allows an understanding of the impact of different stresses but also how that fastener will fail in service. Utilities may then use this knowledge for fastener selection but also to determine inspection cycles for the substation grounds.
In many cases the voltage level of stray currents that are found within the ROW fall below the safety criteria for touch and step potentials, so it is ignored and the effects are not well understood. This can be a fatal flaw in the asset management processes and discharge current may severely reduce the service life of a structure. This video demonstrates the concepts of anodic and cathodic interference and how we may identify each source to mitigate the stray current interference.