What Is PEX EVOH Pipe?

PEX EVOH pipes are a specialized type of cross-linked polyethylene (PEX) pipe that feature an additional layer of Ethylene Vinyl Alcohol (EVOH) on the outer surface. This EVOH layer serves as an oxygen barrier, making these pipes particularly suitable for applications where oxygen ingress could cause corrosion or damage to metal components within a piping system.

The PEX pipe has revolutionized plumbing and heating systems due to its flexibility, durability, and ease of installation. The addition of the EVOH layer enhances these properties by providing a critical oxygen barrier, thereby extending the lifespan and efficiency of the entire system.

Technical Overview of PEX EVOH Pipes

PEX EVOH pipes are engineered through a multi-layer extrusion process. The core layer is made of PEX, a material known for its high thermal and chemical resistance, flexibility, and strength. The outer EVOH layer, typically a few microns thick, acts as a barrier against oxygen permeation. This structure is crucial in systems where metal components are present, as oxygen can lead to corrosion over time.

Key Technical Specifications:

• Material Composition: Cross-linked polyethylene (PEX) with an Ethylene Vinyl Alcohol (EVOH) layer.

• Oxygen Permeation Rate: Significantly lower than traditional PEX pipes, typically less than 0.1 g/m³/day.

• Temperature Range: PEX EVOH pipes can withstand temperatures from -40°C to 95°C, making them suitable for both cold and hot water applications.

• Pressure Ratings: These pipes are designed to handle pressures up to 10 bar, depending on the pipe diameter and application.

Advantages of PEX EVOH Pipes

1. Enhanced Durability:The EVOH layer protects against oxygen ingress, which prevents corrosion of metal components, significantly extending the lifespan of the piping system.

2. Flexibility and Ease of Installation:Like traditional PEX pipes, PEX EVOH pipes are highly flexible, allowing for easy bending and installation with fewer fittings. This reduces the risk of leaks and decreases installation time.

3. Versatility:PEX EVOH pipes can be used in a variety of applications, including radiant floor heating, potable water systems, and industrial applications where oxygen-sensitive components are present.

4. Resistance to Scaling:The smooth interior surface of PEX EVOH pipes resists mineral buildup, ensuring consistent water flow over time and reducing maintenance needs.

Real-World Applications of PEX EVOH Pipes

Radiant Floor Heating Systems:In radiant floor heating, PEX EVOH pipes are a preferred choice due to their ability to prevent oxygen from entering the system, which could otherwise cause corrosion in metal components like manifolds and pumps. In cold climates like Canada and Northern Europe, PEX EVOH pipes are extensively used to ensure efficient heating with minimal maintenance.

Potable Water Systems:PEX EVOH pipes are ideal for potable water systems in residential and commercial buildings, particularly in regions with high metal content in the water supply. The oxygen barrier helps in maintaining the integrity of metal fittings and valves, ensuring a long-lasting and reliable water distribution system.

Industrial Applications:In industries such as pharmaceuticals and food processing, where oxygen-sensitive processes are common, PEX EVOH pipes provide a reliable solution. For example, in breweries, these pipes are used to transport water and other liquids while preventing oxygen contamination that could spoil the products.

Comparison with Traditional PEX Pipes

While traditional PEX pipes offer excellent flexibility, durability, and resistance to chemical degradation, they lack the oxygen barrier provided by the EVOH layer. This makes PEX EVOH pipes a superior choice in systems where oxygen ingress could lead to corrosion and system failures.

Key Differences:

• Oxygen Barrier: PEX EVOH pipes have a significantly lower oxygen permeation rate, making them more suitable for closed-loop systems.

• Longevity: Systems utilizing PEX EVOH pipes tend to have a longer lifespan due to reduced corrosion risk.

Certifications and Standards

PEX EVOH pipes are subject to various international standards, ensuring their quality and reliability in diverse applications. These include:

• ASTM F876/F877: Standards for PEX pipe used in hot and cold water distribution systems.

• ISO 15875: Specifies the performance requirements for PEX piping systems for hot and cold water installations.

• CSA B137.5: Canadian standard for PEX piping systems, including those with EVOH oxygen barriers.

• UNI EN ISO 15875-2: European standard for PEX pipes with oxygen barriers.

These certifications guarantee that PEX EVOH pipes meet stringent safety and performance criteria, making them a trusted choice worldwide.

PEX EVOH pipes represent a significant advancement in piping technology, offering enhanced protection against oxygen ingress while retaining the flexibility and durability of traditional PEX pipes. Whether for radiant heating, potable water distribution, or specialized industrial applications, PEX EVOH pipes provide a reliable and long-lasting solution.

Are you ready to upgrade your plumbing or heating system with PEX EVOH pipes? Contact Edoburg today to explore our range of high-quality PEX EVOH pipes and find the perfect solution for your needs.