Email:sales@bundor.com    |   Tel: +86 150 0225 9955   |   Wechat: Bundor_marketing   |    Skype: +86 150 0225 9955

Home » News » Valve Knowledge

When to choose double eccentric butterfly valve

Posted by Bundor valve
When to choose double eccentric butterfly valve?

Double eccentric butterfly valve, also known as high-performance butterfly valve, is mainly used for drainage of water plants, power plants, steel mill smelting, chemical industry, water source engineering, environmental facilities construction, etc. It is especially suitable for water pipelines as adjustment and interception equipment. Compared with the concentric butterfly valve, the double eccentric butterfly valve is suit for  high pressure, has a longer life and has better stability. Compared with other valves, the larger the diameter, the lighter the material and the lower the cost. However, due to the butterfly plate/disc in the middle, the flow resistance is large, so the butterfly valve smaller than DN200 is meaningless.
Working principle of double eccentric butterfly valve
The double eccentric butterfly valve is further improved on the basis of the single eccentric butterfly valve. Its structural feature is that the shaft center of the valve stem deviates from the center of the disc and the center of the body. The effect of double eccentricity enables the disc to break away from the valve seat immediately after the valve is opened, which greatly eliminates unnecessary excessive extrusion and scratching between the disc and the valve seat, reduces the opening resistance, reduces wear, and improves the Seat life. The scraping is greatly reduced, and at the same time, the double eccentric butterfly valve can also use a metal valve seat, which improves the application of the butterfly valve in the high temperature field.
Structural characteristics of double eccentric butterfly valve
1. Reasonable design, compact structure, easy assembly and disassembly, and easy maintenance.
2. The eccentric structure is adopted to reduce the friction of the sealing ring and prolong the service life of the valve.
3. Completely sealed with zero leakage. Can be used in ultra-high vacuum conditions.
4. Replace the valve plate sealing ring, butterfly plate, shaft and other materials, which can be applied to a variety of media and different temperatures.