How to Address Corrosion in Hydropower Facilities
Posted Apr 18, 2022 by Dave Scaturro
Corrosion is a common problem hydropower facilities need to face as equipment can easily degrade and take place in multiple locations. Usually, corrosion begins to affect a heated zone, also known as the HAZ near the weld regions. During this process, materials are gradually destroyed as chemical reactions work in tandem with the surrounding environment. Along with corrosion, other forms of material deterioration take place including erosive flow and insufficient hydraulic head pressures.
Steps to Take After Noticing Corrosion
Most times, hydropower facilities are located in isolated areas so the reliability of its equipment is essential. As it is necessary to ensure a facility stays on top of any possible deterioration of essential materials, access to spare parts, proper equipment, and maintenance staff requires much planning and preparation.
The metal replacement or overlay process is commonly used when repairing hydroelectric runners after noticing corrosion. This technique actually doesn’t really do much to break the natural cycle of corrosion. In fact, reducing corrosion would require one to alter the material’s technology base by changing it to a base that can withstand oxidative corrosion. Altering the base of a certain material is a very time consuming process which consists of much heat, risks of stress cracking, and more. The systems that help to avoid distortion during the rigorous process can also be very costly. Despite all of these issues, the process does yield the desired effect, especially if protective polymer-based coatings are incorporated into the treatment.
The use of reinforced epoxies will lead to improvement in certain properties like: erosion/abrasion resistance, flexibility, and permeability. Reinforced epoxies do come with both pros and cons; one con being it can create severe cavitation, which is common. Before epoxy-based coatings can be used, proper surface preparation and techniques must be applied in order for the coating systems to operate efficiently.
Certain industrial coatings will be successful repair options in response to corrosion. They are also more budget friendly and less time consuming in comparison to other processes that help prevent issues caused by corrosion.
Tips for Finding the Best Kind of Protective Coating
- Be sure to pay attention to the characteristics of how the product performs
- Do research on the application’s complexity including its surface preparation, consistency and ease of usage
- Look into the availability of the material that you need
- Determine the cost and availability of skilled labor to install per manufacturer’s instructions
- Search for high-adhesive bond strengths, cured surface finishes, corrosion resistance, and erosion resistance
- Get recommendations from professionals or do research on decontamination, profile blasting and cleanliness, and environmental conditions during application
Alpine has many years of experience maintaining hydropower facilities and addressing issues with corrosion before and after they take hold. Our scope of industrial site painting, preparation and coating includes aggressive surface preparation techniques and specialized coatings. Reach out to our talented team of professionals who can handle just about any industrial maintenance situation.