By: Kendall Smith, Induron T&D Market Manager
While it seems we were just discussing decades-long lack of relevant standards for the unique challenges within the electric utility T&D market for coatings and corrosion control, the opposite is now somewhat true! There are several standards, specifications, and other documents available to achieve these goals!
We at Induron Coatings can help you build a coatings program that can be integrated into an asset management program, which can help you very effectively extend the useful life of your T&D assets. And, the time to build a program is now! The total number of T&D assets keeps growing, and the number of structures that need help now keeps increasing!
Standards to Know
From a big picture perspective, the closest thing to a universal standard may be the ISO standards. ISO 12944 is a globally-recognized standard that lays out the rules and guidelines for the protection of assets from corrosion by use of coating systems and paint. It was introduced in 1998, updated in 2007 and revised a second time in 2018.
The standard covers paint and coatings for steel structures in atmospheric, immersed, and buried environments. For the T&D industry, it greatly helps evaluate the T&D structures. You can grade the level of corrosion, the corrosiveness of the environment, the rate of corrosion, and several other variables.
Plus, back in 2007, NACE and IEEE started having meetings regarding industry-specific standards for corrosion and coatings in T&D. These conversations have led to many standards that can greatly help specifiers, such as:
- NACE SP0415-2015/IEEE Std 1895-SG, NACE International and IEEE Joint Standard Practice for Below-Grade Inspection and Assessment of Corrosion on Steel Transmission, Distribution, and Substation Structures
- NACE SP0215-2015/IEEE Std 1839-SG, NACE International and IEEE Joint Standard Practice for Below-Grade Corrosion Control of Transmission, Distribution, and Substation Structures by Coating Repair Systems
- NACE SP21459-2020/IEEE Std 2655-2018, “Atmospheric Above Grade Inspection and Assessment of Corrosion on Steel Electrical Transmission, Distribution, and Substation Structures”
- NACE SP0315-2015/IEEE Std 1835-SG, “Standard for Atmospheric (Above Grade) Corrosion Control of Existing Electric Transmission, Distribution, and Substation Structures by Coating Systems”
These four standards guide you in writing effective coatings specifications for T&D structures. Keep in mind that abrasive blasting is rarely, if ever, an option—so surface-tolerant coatings with excellent wetting properties are essential. Since aged coatings will remain on the existing substrate, the new coating must have very low curing stress for successful overcoating. Additionally, adequate wet and dry film thickness is necessary to ensure durability for up to 25 years, typically requiring 8-10 mils DFT in a single coat. Finally, high-quality barrier pigments enhance adhesion to various substrates, improve protection against the elements, reduce permeability, increase abrasion resistance, and make the coating tougher overall.These properties, along with several other features and benefits, will help the coating perform in much less than ideal conditions!
Some industry groups, and even entire countries, have created standards and specifications to assist building excellent corrosion control systems and programs. For instance, drones, LiDAR, and new asset management software have created the ability to predict the reliability and safety of assets, which in turn reduces cost and liability.
Likewise, FERC has endorsed capitalizing the use of coatings for extending the life of T&D assets. Engineering companies and large service companies offer technical and financial advisory support to evaluate, plan, and perform the work needed to protect and upgrade the grid! Further, analytics-driven data gathering can even help utilities detect metal loss on a structure exposed to increasing winds and evaluate/prevent metal loss that would eventually weaken that structure in extreme weather events. All the tools needed to mitigate risks and maintain ASCE standards are available now!
So, all this to emphasize, you can’t just “wait it out” as the effect of time and corrosion will certainly make the structure more vulnerable to extreme weather events, especially higher winds!
Contact Induron TODAY to protect your power grid for reliable energy delivery.