Galvanized Iron (GI) pipes are commonly used in compressed air systems due to their affordability. However, when exposed to humid air, these pipes can rust, compromising the quality of the compressed air and posing significant safety risks. This case study examines the factors contributing to the corrosion of GI pipes in compressed air systems and the potential consequences for applications demanding stringent air quality standards.
Factors Contributing to Rusting
- Moisture Content in Compressed Air: The primary cause of rust in GI pipes is the presence of moisture in the compressed air. This moisture can come from various sources, including atmospheric humidity, leaks in the system, and improper drainage. When moisture condenses within the pipe, it creates a corrosive environment that accelerates the oxidation process.
- Pipe Quality and Condition: The quality and condition of the GI pipe itself can influence its susceptibility to rust. Pipes with defects, such as scratches or pits, can provide entry points for moisture and contaminants, increasing the risk of corrosion. Additionally, the thickness of the zinc coating on the pipe plays a crucial role in its resistance to rust.
- System Design and Maintenance: Inadequate system design and maintenance practices can contribute to rusting. For example, if the air dryer is not functioning properly or if the system lacks adequate drainage, moisture can accumulate and lead to corrosion.
Consequences of corrosion in GI Pipes
- Contamination of Compressed Air: Rust particles can contaminate the compressed air, leading to a variety of problems. These particles can clog filters, valves, and other components, reducing system efficiency and increasing maintenance costs. Additionally, rust can introduce contaminants into products that rely on compressed air, such as food and pharmaceuticals, compromising their quality and safety.
- Safety Risks: Rusted GI pipes can pose significant safety risks. If a pipe ruptures due to corrosion the release of high-pressure air can cause serious injuries or property damage. Moreover, rust particles can ignite in the presence of a spark or flame, leading to fires and explosions.
Mitigation Strategies
To prevent the rusting of GI pipes in compressed air systems and ensure the quality and safety of the compressed air, several mitigation strategies can be implemented:
- Air Drying: Install a high-quality air dryer to remove moisture from the compressed air before it enters the pipe system.
- Regular Maintenance: Conduct regular inspections and maintenance of the compressed air system to identify and address potential issues, such as leaks or clogged filters.
- Pipe Selection: Choose GI pipes with a thick zinc coating and avoid pipes with defects.
- System Design: Ensure that the compressed air system is designed to minimize moisture accumulation and promote proper drainage.
- Corrosion Inhibitors: Consider using corrosion inhibitors in the compressed air system to help protect the pipes from rust.
A Real-World Example
A client recently approached us with a problem. Their compressed air system, which relied on traditional GI pipes, was experiencing frequent breakdowns and inconsistencies in air quality. Upon inspection, we discovered extensive rusting within the pipes. This confirmed our suspicions – the moisture content in the compressed air was causing the GI pipes to deteriorate.
A Solution with AirNet Piping
Fortunately, we were able to offer a solution. We recommended replacing the client’s existing GI pipes with the Atlas Copco AirNet piping system. AirNet offers several advantages over traditional GI pipes:
- Corrosion-resistant materials: AirNet pipes are available in aluminum and stainless steel, both of which are highly resistant to corrosion, even in humid environments.
- Lightweight and modular design: AirNet pipes are lightweight and easy to install, making them ideal for retrofitting existing systems. The modular design also allows for easy expansion or modification in the future.
- Leak-free connections: AirNet uses a unique push-fit connection system that eliminates the need for welding or threading, reducing the risk of leaks and ensuring clean, efficient air flow.
Positive Outcome
By replacing the client’s GI pipes with the AirNet system, we were able to significantly improve the reliability and efficiency of their compressed air system. The client has experienced:
- Reduced maintenance costs: Fewer breakdowns and the elimination of rust-related issues have led to a significant reduction in maintenance costs.
- Improved air quality: The use of corrosion-resistant materials ensures clean, contaminant-free air, which is critical for their specific application.
- Peace of mind: The client can now rest assured that their compressed air system is safe and reliable, minimizing the risk of accidents or disruptions.
Facing compressed air system issues? Contact Ren Engineering Solutions today. We’ll assess your situation and provide expert recommendations to optimize your system’s performance and efficiency.
Lorna Olum
Applications Engineer,
Ren Company Limited
T +254741159200