Issues regarding the use of three-eccentric butterfly valves
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I have heard from the manufacturer about three-eccentric butterfly valves, and from a theoretical perspective it seems like they should be quite good – overcoming the shortcomings of ordinary butterfly valves as well as double-eccentric butterfly valves. However, I saw someone online recently say that there are also significant problems with using three-eccentric butterfly valves, which makes me confused. Is this product really practical? In what situations can it be used effectively?
Key features: 1. Low torque – after rotating it a few degrees, there is virtually no friction between the valve disc and the seat. 2. Tight sealing – face-to-face sealing, combined with multi-layer PTFE or graphite soft seals, enables zero leakage. 3. High operating temperature – metal-to-metal sealing can withstand temperatures of several hundred degrees. 4. High pressure rating – it can handle pressures up to 900/1500 psi. Triple eccentric design is mainly used for on/off applications, while double eccentric design is more often used for regulating purposes; many foreign manufacturers of control valves offer double eccentric designs but not triple eccentric ones. The three eccentricities need to be carefully designed and calculated; otherwise, jamming and leakage are inevitable. If the eccentric angle is incorrect, the sealing ring on the valve plate will be damaged after just one closure.
It depends on the process; triple eccentric design works well in high-temperature environments as well as when the medium contains slight amounts of impurities. The biggest problem is that it’s much more expensive than the double eccentric type.
Are there any other questions? I would like to ask again whether the shaft of the valve is vertical or horizontal after installation. This direction affects the direction of the control lever. If it is placed horizontally, will friction in the bearings or any gaps affect the downward movement of the disc, leading to leakage?
It’s usually in a vertical direction, of course it depends on your requirements!
For pipe diameters of DN400 and above, at temperatures above 200 degrees, triple-eccentric butterfly valves are recommended for applications suitable for butterfly valves
The hard-sealed triple-eccentric butterfly valve features high regulation accuracy; its adjustable ratio is more than twice that of ordinary butterfly valves. It is suitable for applications involving particles, as well as high temperature and high pressure conditions
Our company’s strength lies in manufacturing large-diameter metal-sealed triple-eccentric butterfly valves that meet zero-leakage requirements
Did it say upstairs that a level 6 seal can be achieved? - - - - - --