Triple Eccentric Butterfly Valves – An Inside Look

Jun 7, 2023 | News

Butterfly valves are widely used in fluid control applications for their compact design and ability to handle high flows. One type of butterfly valve is the triple eccentric butterfly valve, specifically designed for higher performance.

Some Key Benefits Of Eccentric Design

China triple offset butterfly valve

In a standard butterfly valve, the disc rotates about an axis that is concentric with the valve body. However, in a triple eccentric butterfly valve, the disc rotates about three separate axes. This eccentric design introduces some key benefits:

1. Lower torque – Since the disc does not have to rotate directly about the valve body, it requires less torque to operate. This makes triple eccentric butterfly valves easier to open and close, especially for large sizes.
2. Reduced wear – Since the disc does not rub directly against the valve body when closing, there is less wear on both the disc and valve body. This extends the overall service life of the valve.
3. Improved tight shut-off – The disc can be machined with an exact seal shape for the body, improving the tightness of closure and preventing leakage when the valve is fully closed.
4. Eliminates disc deflection – Because the disc does not have to flex as much to form a seal, triple eccentric butterfly valves experience less stress and distortion of the disc when closing.

They are typically made of cast or ductile iron for the valve body with stainless steel or alloy discs. Ratings can extend up to 600 psi pressure and temperatures from -20 to 300 degrees Fahrenheit depending on the materials and seals used.

Triple Eccentric Butterfly Valves’ Applications

Triple eccentric butterfly valves are commonly used for applications requiring low operating torque, tight shut-off, and infrequent operation, like throttling service in power plants, chemical processes and other industrial systems.

Overview About Triple Eccentric Butterfly Valves

In short, triple eccentric butterfly valves offer several advantages over standard concentric butterfly designs thanks to their eccentric disc rotation. The lower torque, reduced wear, improved shut-off and lack of disc deflection make triple eccentric butterfly valves a good choice for many critical control valve applications.