The dual disc check valve is a type of non-return valve designed to prevent reverse flow of media. It features two symmetric semicircular discs, making it widely used in various fluid transportation systems.
Working Principle
The two discs inside the valve are connected to a central shaft via hinges. When the medium flows forward, the pressure pushes the dual discs to rotate around the shaft and open, creating an unobstructed flow path. If reverse flow occurs, the discs quickly close under the action of reverse pressure and their own gravity, tightly fitting the valve seat to block backflow, thus protecting pipelines and equipment from damage such as water hammer.
Structural Features
- Dual Disc Design: The two symmetric discs minimize flow resistance when open. When closed, they provide a large sealing area, ensuring reliable sealing performance and reducing water hammer impact.
- Material Selection: The valve body is often made of cast iron, carbon steel, or stainless steel to adapt to the corrosiveness, temperature, and pressure requirements of different media (such as water, steam, oil products). The discs and valve seat usually adopt metal-to-metal or rubber sealing to balance wear resistance and sealing.
- Compact Structure: Compared with single-disc check valves, it has a more compact size, suitable for scenarios with limited installation space.
Applications
It is commonly used in water supply and drainage systems, heating pipelines, industrial circulating water systems, petrochemical plants, etc. It is particularly suitable for large-diameter pipelines (e.g., DN100 and above), efficiently controlling the one-way flow of high-flow media with both stability and economy.
With advantages such as quick opening and closing, low flow resistance, and strong water hammer resistance, the dual disc check valve has become an important component to ensure the safe operation of pipeline systems.