A triple eccentric butterfly valve is a type of actuated, hard-sealing valve that can be used to control high-temperature steam discharge. This type of valve has an angled position in relation to the seats, which minimizes seat damage as well as preserves the integrity of the sealing surface. It also reduces the likelihood that the valve sticks to the seats and lowers operating torque. Go here: shiphamvalves.com
In addition to providing a more durable seal, triple eccentric butterfly valves can operate at higher flow rates and temperatures than their standard counterparts. This type of valve also offers the benefit of reduced maintenance costs and a quicker shutoff compared to other metal seated valves.
Triple Eccentric Butterfly Valves in Water Treatment: Efficiency and Reliability
The three-eccentric design of this valve features a rotating cam that allows the butterfly plate to be separated from the valve seat, which eliminates contact and scraping during opening and closing. This design also provides a more complete compression seal that eliminates the need for elastomers and other soft materials in valve trim, which can wear out over time.
A recent study examined the effect of high-temperature, steam-induced vibration in a triple-eccentric butterfly valve. The study was conducted using numerical simulation and experimental modal analysis methods. The results show that the main frequencies of steam pressure fluctuation and shedding of vortices near the valve disc are close to the natural frequency of the valve disc-stem assembly, which means the assembly can resonate. This resonance can cause the two sealing surfaces above and below the disc to become worn or damaged, and this can also damage the drive engagement surfaces of valve actuators.