The inherent vibration frequency of electric butterfly valve is low
(1) The electric butterfly valve is connected to the additional air chamber, but the natural vibration frequency of the electric butterfly valve device is reduced to 0.5-3Hz. Under any load, the electric butterfly valve can maintain a low and nearly equal vibration frequency.
(2) Four conclusions are drawn from the research on the construction of electric butterfly valve in the additional air chamber; The system damping ratio first increases and then decreases with the increase of the orifice diameter, so the orifice opening control can realize the simultaneous adjustment of the stiffness and damping of the electric butterfly valve system.
(3) The increase of excitation frequency will increase the system stiffness and natural frequency, and reduce the damping ratio. Therefore, high-frequency excitation is not conducive to the reduction of stiffness of the additional air chamber and the damping effect of the orifice.
(4) When the working height is constant, the change of static load of electric butterfly valve with additional air chamber has little effect on the system damping and natural frequency.
(5) When the volume ratio of the auxiliary main air chamber is less than 2, increasing the volume of the auxiliary air chamber can reduce the system stiffness; Increasing the volume of the additional air chamber can also increase the damping ratio of the system, which is conducive to vibration attenuation.