What is a Triple Eccentric Butterfly Valve?

Triple eccentric butterfly valve, also called triple offset butterfly valve, is a high-performance butterfly valve. The triple eccentric butterfly valve was developed to make up for the defects of the double eccentric butterfly valve and is an improvement on the double eccentric butterfly valve.

Triple Offset Butterfly Valve is an industrial valve used to open and close a pipeline's working medium passage, and for flow control. The valve has three offsets, or machined conical profiles, that create a cam-like motion when the valve operates:

1. First offset: Provides continuous sealing;

2. Second offset: Allows the valve to open with minimal friction, which extends its life;

3. Third offset: Allows the seat and seal ring to rotate without interference, which eliminates rubbing and reduces wear;

Triple Offset Butterfly Valve's design offers several benefits, including:

1. Frictionless sealing: The metal-to-metal seal allows for a tight shutoff in high-pressure and high-temperature systems;

2. Low torque: The valve is easier to automate than other metal seated valves;

3. Reduced maintenance: The lack of cavities between sealing components minimizes maintenance costs;

4. Field replaceable parts: The seat and seal ring can be replaced, which further reduces maintenance costs;

Triple eccentric butterfly valve is designed as Metal to Metal Seats, so it is widely used in high temperature environment, such as materials 321, 310S, C276, etc., the highest temperature can reach 1000℃ (1832℉).

In addition, the triple eccentric butterfly valve can be made of Monel 400 material, which has a good effect on resisting seawater corrosion; it can also be made of duplex steel UNS S31803, which has an excellent effect on resisting chloride ions in high-salinity wastewater.

Freeman Valve can provide the following two types of triple eccentric butterfly valves for different media:

1. For non-granular media: 

    we provide "metal + PTFE" (temperature ≤ 200℃) Disc, or "metal + graphite" (temperature ＞ 200℃) Disc. 

    This Disc is equivalent to a soft-seal butterfly valve and can achieve Class A leakage.

2. For granular media or media containing particles: 

    we provide "metal + STELLITE" Disc to prevent particles in the medium from wearing the valve seat.