Engineering and Maintenance for Cathodic Protection Systems Combined with Vinyl Coatings

Project ID: 22037
Principal Investigator: Grace Weber
Research Topic: Improved Power Generation
Funded Fiscal Years: 2022, 2023 and 2024
Keywords: None

Research Question

Question 1: What is the susceptibility of the vinyl zinc-rich coating systems to cathodic protection (CP)?

To answer this question, the proposed work will use a combination of desktop review, laboratory testing, and field surveys. The desktop review will correlate photographs of blistering and polarization data from previous S&T funded research projects. Through laboratory testing, researchers will replicate field conditions and polarization to determine the effect of varying polarization levels on vinyl-coated test structures. Using field surveys, researchers will inspect existing structures with vinyl coatings and CP at both Reclamation and USACE facilities. The field survey will include visual inspection and photographs of blistering or other coating defects and measurements of CP polarization levels.

Question 2: How can we use that information to develop guidance for designing and maintaining CP systems and specifying vinyl coating systems?

At both Reclamation and USACE, there are already facilities with structures or equipment coated with the vinyl zinc-rich system and protected with CP. Facility operators must stay well below the level of overpolarization (instant-off electrical potential of -1.1 volts as referenced by a copper/copper-sulfate reference electrode) to avoid the risk of damaging the coating. However, this limit is based only on circumstantial observation with no quantitative data or publications to determine the appropriate amount of polarization. The outcomes of the proposed research, as described under Question 1, will provide quantitative data on the susceptibility of vinyl coatings to CP. Better understanding of the interactions between CP and vinyl coatings will allow the TSC to provide meaningful and substantiated guidance on the appropriate level of cathodic polarization on vinyl-coated structures.

Need and Benefit

Vinyl coatings are commonly specified for high impacted immersion service, where the structure is immersed and impacted by debris or other potentially erosive materials. The research will improve design guidance and repair/maintenance strategies for vinyl coatings used with CP systems, increasing the vinyl coatings reliability and extending service life. Lead researcher had a phone call with S&T PE coordinator, Erin Foraker, to discuss the proposal and SSIP need.

Contributing Partners

Contact the Principal Investigator for information about partners.

Research Products

Contact the Principal Investigator for information about these documents.

Return to Research Projects

Last Updated: 6/22/20