When it comes to waterworks and pipeline systems, choosing the right type of flange is crucial for safety, efficiency, and longevity. One commonly used type is the AWWA flange, which plays a vital role in connecting pipes and ensuring leak-proof water transmission.
In this blog, we’ll break down what AWWA flanges are, their types, uses, and how they differ from other industrial flanges.
What is an AWWA Flange?
AWWA stands for the American Water Works Association, an organization that sets standards for water treatment and distribution. AWWA flanges are pipe flanges designed in accordance with the AWWA C207 standard. These flanges are specifically intended for use in low-pressure water service applications such as municipal water supply systems, irrigation systems, wastewater treatment plants, and other non-critical water projects.
Key Features of AWWA Flanges
- Standard: AWWA C207 (latest revision)
- Pressure Ratings: Class B (up to 86 psi) to Class F (up to 300 psi)
- Material: Usually made from carbon steel or ductile iron
- Applications: Used in waterworks systems—not typically used for high-pressure, high-temperature industrial piping
- Sizes: Commonly available from 4 inches to 144 inches
Types of AWWA Flanges
AWWA flanges are generally divided into four main types based on their pressure class:
| Flange Class | Pressure Rating (psi) | Description |
|---|---|---|
| Class B | Up to 86 psi | Used in light-duty water systems |
| Class D | Up to 175 psi | Most commonly used in municipal piping |
| Class E | Up to 275 psi | Heavy-duty applications |
| Class F | Up to 300 psi | Extra heavy-duty use cases |
AWWA Flange Face Types
- Flat Face (FF): Most common face type for AWWA flanges, suitable for waterworks gaskets
- Ring-Type Face: Rare in AWWA applications
Applications of AWWA Flanges
AWWA flanges are ideal for:
- Municipal Water Systems
- Sewage and Wastewater Treatment Plants
- Irrigation Projects
- Hydropower Plants
- Fire Protection Systems
AWWA Flanges vs. ANSI/ASME Flanges
| Feature | AWWA Flange | ANSI/ASME Flange |
|---|---|---|
| Use Case | Waterworks, low-pressure | Industrial, high-pressure & temp |
| Pressure Rating | Up to 300 psi | Can go up to 2500 psi |
| Standards Followed | AWWA C207 | ASME B16.5, B16.47 |
| Materials | Carbon Steel, Ductile Iron | Stainless Steel, Alloy Steel, etc. |
| Cost | More affordable | Higher due to specifications |
Final Thoughts
If you’re involved in water distribution, fire protection, or similar infrastructure projects, AWWA flanges are a reliable and cost-effective choice. Their design ensures easy installation, durability, and compatibility with various piping systems—making them a preferred option for waterworks engineers and contractors.