Galvanized Steel Unions Combat Corrosion in Piping Systems

Have you ever been frustrated by the frequent need to replace pipes in your home or commercial building? Electrochemical corrosion, an invisible destroyer, silently eats away at your investment. The connection between different metals, though seemingly insignificant, can become a potential source of galvanic corrosion. This article explores how galvanized steel dielectric unions can effectively solve this problem and protect the long-term stability of your piping systems.

Galvanic Corrosion: The Invisible Threat to Piping Systems

Galvanic corrosion, also known as bimetallic corrosion, occurs when two dissimilar metals come into contact in the presence of an electrolyte (such as water), forming an electrochemical cell. The more active metal loses electrons through oxidation, gradually corroding. In piping systems, common metal combinations like copper and steel are particularly susceptible to this phenomenon. Over time, pipe walls thin out, potentially leading to leaks that create both financial losses and safety hazards.

Dielectric Unions: An Effective Barrier Against Corrosion

Dielectric unions, sometimes called insulating unions, are specialized fittings designed to connect pipes made of different metals. Their primary function is to use insulating materials to separate the two metals, thereby preventing the formation of electrochemical cells and stopping galvanic corrosion. The ProLine Series galvanized steel dielectric unions represent an excellent solution specifically engineered to address this problem.

Advantages of ProLine Series Galvanized Steel Dielectric Unions

• Galvanized Steel Construction: The zinc coating provides a protective barrier that slows corrosion and extends service life.
• Insulating Washer: The union's internal insulating washer is crucial—it effectively prevents direct contact between dissimilar metals, interrupting the electrical current path and fundamentally inhibiting galvanic corrosion. These washers are typically made from rubber or other corrosion-resistant insulating materials that maintain stable insulating properties across various water conditions.
• Multiple Connection Options: The female iron pipe (FIP) × female iron pipe (FIP) connection design allows for easy installation with various standard piping systems.
• Excellent Sealing: Equipped with rubber gaskets that create watertight seals when properly tightened, preventing leaks and ensuring safe system operation.
• Wide Application Range: Suitable for water systems up to 180°F (82°C) and working pressures up to 200 PSI WOG (water, oil, gas), meeting requirements for both commercial and residential plumbing systems.
• ANSI Compliance: Threaded ends comply with ANSI B1.20.1 standards, ensuring reliable connections and interchangeability.

Selection and Installation Considerations

• Material Selection: Choose union materials based on your specific system environment and medium characteristics. For highly corrosive media, select materials with superior corrosion resistance.
• Size Compatibility: Ensure union specifications match your piping system to avoid loose connections or leaks from size mismatches.
• Proper Installation: Follow correct installation procedures, avoiding both overtightening and insufficient tightening to maintain proper seals.
• Regular Inspection: Periodically check unions for visual defects and connection integrity, replacing or repairing any problematic units immediately.

Case Study: Dielectric Unions in Action

A commercial building's hot and cold water piping system, constructed with both copper and steel pipes, had long suffered from galvanic corrosion. Frequent pipe leaks led to exorbitant maintenance costs. During pipe replacement, engineers installed ProLine Series galvanized steel dielectric unions to isolate the dissimilar metals. After implementation, corrosion decreased significantly, leaks became rare, maintenance costs dropped substantially, and building safety improved.

Conclusion

Galvanic corrosion poses a significant threat to piping systems, and ProLine Series galvanized steel dielectric unions provide an effective solution. By interrupting electrical current between dissimilar metals, they prevent galvanic corrosion, extend system lifespan, reduce maintenance costs, and ensure safe operation. Selecting appropriate dielectric unions during system design, installation, and maintenance is crucial for long-term piping system stability.