Which Electrodes Can Be Effectively Controlled by Sacrificial Anodes

In modern industry and daily applications, different types of electrodes play a vital role. As industrial production becomes increasingly sophisticated, the function and application of various electrode products — especially sacrificial anodes — have become more prominent and widespread. However, the performance and effect of different anode products often vary depending on their material and application methods. Let’s explore the insights shared by industry experts.

Understanding the Role of Sacrificial Anodes

According to experts specializing in the research and production of aluminum alloy anodes, compared with traditional anode products, sacrificial anodes demonstrate significant advantages. However, if they are not used correctly, their effectiveness cannot be fully realized. So, what exactly are the functional characteristics of sacrificial anodes, and which electrodes can they effectively control?

Unique Features and Applications in Cathodic Protection

From a technical perspective, the flat and flexible structure of sacrificial anodes allows them to be easily shaped and adjusted. These properties make them particularly useful in cathodic protection systems, especially in long-distance pipelines, large storage tanks, grounding networks for lightning protection, and composite anodes used for short-term protection.

Calculation of Protection Current and Environmental Factors

In practical applications, the required protection current for steel piles is calculated based on the protection current density and surface area of each section. The value of sacrificial anode protection current density varies depending on the country, region, corrosion zone, and whether the steel structure is bare or coated. In seawater, the protection current density for bare steel is typically around 150 mA/m².

Factors such as geographic location, medium resistivity, port structure, material type of steel piles, surface conditions, coating type and thickness, and coating service life must all be considered. By referencing relevant standards and engineering experience, engineers can determine the appropriate protection current density and calculate the total protection current for each section.

Principle of Sacrificial Anode Control

In essence, sacrificial anodes protect steel structures by connecting them to a more reactive metal or alloy that more readily loses electrons. This approach is most economically applied to structures that require small protection currents and are located in low-resistivity environments.

Types of Electrodes Controlled by Sacrificial Anodes

1. In soil environments, saturated copper-copper sulfate reference electrodes and high-purity zinc reference electrodes are commonly used.        In aqueous media, high-purity zinc and silver/silver chloride reference electrodes are preferred.

2. The main electrodes controlled by sacrificial anodes include:        long-life saturated copper-copper sulfate reference electrodes, high-purity zinc reference electrodes, silver/silver chloride reference electrodes, and molybdenum dioxide reference electrodes.

3. The molybdenum dioxide reference electrode is primarily used in concrete environments.        The service life of a saturated copper-copper sulfate reference electrode is generally less than 10 years, while other reference electrodes can be selected or designed based on their lifespan requirements.

Conclusion

Sacrificial anodes play a crucial role in controlling and protecting various types of reference electrodes used in corrosion monitoring and cathodic protection systems. By selecting suitable electrode types and maintaining precise control over protection current and material compatibility, engineers can ensure long-term safety and efficiency in both industrial and civil engineering applications.