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1) The method of changing the direction of the unbalanced force: In stability analysis, it is known that when the direction of the unbalanced force is the same as the direction in which the valve tends to close, that is, when it exerts a force that causes the valve to close, the valve’s stability is poor. When the valve operates under the conditions of such unbalanced forces, the method of changing the direction of their action is employed; usually, this involves changing the valve from a flow-blocking type to a flow-allowing type, and this generally allows the stability issue of the valve to be resolved easily. 2) Avoiding operation in the valve’s own unstable region: Some valves, due to limitations in their structure, exhibit poor stability when operating at certain opening degrees. ①For two-seat valves, when the opening degree is within 10%, flow occurs at the upper ball while it is blocked at the lower ball, resulting in instability; ② The stability is poor in the vicinity where the slope of the unbalanced force changes intermittently. For butterfly valves, the transition point is around 70 degrees; for two-seat valves, it is at an opening degree of 80–90%. When encountering such valves, operating in the unstable region will inevitably result in poor stability; avoiding operation in that region is sufficient. 3) Replace it with a valve that has good stability; such valves exhibit minimal changes in unbalanced forces and provide good guidance. Among the commonly used ball valves, sleeve valves possess this significant feature. When single- and double-seat valves have poor stability, replacing them with cartridge valves will definitely improve stability. 4) The ability of the actuator based on the method of increasing spring stiffness to resist the impact of load changes on stroke depends on the spring stiffness; the greater the stiffness, the lesser the impact on stroke, and the better the stability of the valve. Increasing the spring stiffness is a common and simple method to improve valve stability; for example, replacing springs with a stiffness range of 20–100 KPa with springs having a higher stiffness of 60–180 KPa. This approach is mainly used for valves equipped with positioners; otherwise, a positioner must be installed separately on the valve. 5) Method of reducing response speed: When the system requires that the response or adjustment speed of the control valve not be too fast, yet the valve’s response and adjustment speed are actually high. For example, when fine tuning of flow rate is needed but the flow regulation capability of the control valve is significant; or when the system itself is already a fast-response system but the control valve is equipped with a positioner to further accelerate its operation – all these situations are undesirable. This will result in overshoot and vibrations, etc. To address this, the response speed should be reduced. The solutions are: ① Change the linear characteristic to a logarithmic one; ② A device with a positioner can be replaced by a converter or an actuator. 6) Changing the flow direction to resolve the valve-closing issue and eliminate surging; two-position valves are typically used in the flow-blocking mode to improve the shut-off effect. In liquid media, the unbalanced forces resulting from flow closure press the valve core shut, exerting a force that promotes closing; this is also known as suction effect. It accelerates the movement of the valve core, causing slight water hammer and leading to system surging. The solution to the above phenomenon is to change the flow direction to outward, and the surge will be eliminated. For problems similar to this, where the act of promoting closure affects the proper functioning of the valve, this approach can also be considered as a solution. 7) The most typical valve for overcoming fluid disruption is the double-seat valve; the fluid enters from the middle, the valve core is perpendicular to the inlet, and the fluid flows around the valve core and exits in two streams, one above and one below. The flow impact on the valve core pushes it toward the outlet side, causing friction that damages the guiding surfaces of the valve core and the bushing, leading to abnormal operation. High flow rates can also cause the valve core to bend or erode, and in severe cases, even break. Solutions: ① Increase the hardness of the material in the guiding area; ② Enlarge the size between the upper and lower balls of the valve core to make it thicker; ③ Use another type of valve as a substitute. When a sleeve valve is used, the fluid flows in from around the sleeve, thereby **reducing** the lateral force on the valve plug. 8) The method of overcoming the rotational force generated by the fluid to rotate the valve core applies to valves with a “V”-shaped port; due to the asymmetric flow of the medium, the tangential forces acting on the valve core at the “V”-shaped port are not uniform, resulting in a rotational force that causes it to spin. This is especially true for valves with DN≥100. As a result, it may cause the valve to detach from the actuator push rod, and springless actuators may cause the diaphragm to twist. Solutions include: ① Rotating the valve core in the opposite direction by an angle to balance the tangential forces acting on it; ② Securing the connection between the valve stem and the push rod further, and adding a anti-rotation clamp if necessary; ③ Replacing the valve core with a plug-type valve core; ④ Using or switching to a sleeve-type structure; ⑤ If the rotation is caused by resonance, eliminating the resonance will resolve the issue. 9) Adjust the friction of the butterfly valve disc to overcome opening oscillation. Butterfly valves that use soft seals such as \"O\"-rings, sealing rings, and linings achieve a very satisfactory shut-off effect when closed, as the deformation of these soft seals ensures that the disc closes properly and covers it completely. However, when the valve is to be opened, the actuator must exert an increasing force on the valve disc; once this force equals the frictional force exerted by the soft seal on the valve disc, the valve disc begins to move. Once activated, this friction force decreases sharply. To achieve force balance, the valve disc opens violently; when this force, together with the unbalanced torque generated by the medium at that opening degree, balances the opening torque of the actuator, the valve stops at that opening degree. The opening angle resulting from this violent and sudden jump can reach 30–50%, which will lead to a series of problems. At the same time, during shutdown, significant changes occur in the soft seals, which can lead to permanent deformation or damage as a result of being squeezed or strained by the valve plate, thereby affecting their lifespan. The solution is to adjust the friction force exerted by the soft seal on the valve disc during startup, which ensures that the required cutting performance is achieved while also allowing the valve to start functioning properly. The specific methods include: ① Adjusting the amount of interference; ② Reducing the difficulties associated with opening caused by excessive closure of the valve plate, by using limits or by adjusting the pre-tensioning force and output force of the actuator