Pneumatic valve actuator fault resolution will go to choose a more suitable pneumatic actuator, pneumatic actuator with higher cost performance, then we must first understand the types of actuators, actuators can be divided into pneumatic actuators and electric actuators, the more commonly used actuators are these two types, we will choose pneumatic actuators when we choose.
Then we have to choose the actuator according to the size of the air source. The torque required to turn the valve is too large to understand. If the valve is too large, the service life of the valve is not long. Generally, 30% allowance for torque is OK. Pneumatic actuator can be seen from the text that this kind of actuator is operated by pneumatic force. Compared with the electric actuator, it can adapt to more environments, and its reasonable structure makes its load force larger, and achieves the goal of high torque output. At the same time, compared with the electric actuator, the action is faster and the reaction is faster. Of course, the electric actuator also has many advantages that the pneumatic actuator can't compare with. The advantages of the pneumatic actuator are also those that the current electric actuator does not have. Both of them have their own disadvantages and advantages. Therefore, under the continuous development of science and technology in the future, the cost-effectiveness of the two will be greatly improved.
Secondly, we assess the installation platform, select the actuator for each environment, there is a standard for the actuator, we should find the corresponding standard according to the valve. As a kind of pneumatic actuator, its function in valve is to make the valve device more convenient in use. Because of the connection of the pneumatic actuator, the valve can drive the valve body parts to move quickly when it operates in the pipeline, which has a certain automation effect. Moreover, because the actuator itself is energy driven, it has certain value for the drive of the valve body opening and closing parts. This kind of valve is used in the fluid pipeline for opening and closing due to its small fluid resistance.
The common faults are that the valve body does not act, the valve cannot be closed to zero position, the pneumatic actuator has no feedback signal, and the signal pressure is unstable. There are some special faults, such as pneumatic actuator control valve vibration. Next, we mainly analyze the causes and treatment measures of the special fault control valve vibration.
The vibration of the control valve of pneumatic actuator will cause the control system to fail to work normally. The vibration causes are as follows:
1. External vibration source, that is, the equipment pipe itself has vibration.
2. The selection of pneumatic actuator control valve does not meet the selection requirements, such as unsuitable flow characteristics, valve diameter is too large, poor spring stiffness and so on, resulting in control valve vibration.
3. It is eroded by the fluid and produces vibration.
Troubleshooting measures for pneumatic valve actuator: if it is found that the vibration is inherent in the equipment pipeline, the equipment pipeline can be cleaned and readjusted to make the vibration disappear. If it is the problem of the control valve of pneumatic actuator, the limiting orifice plate can be used to absorb part of the pressure drop, reduce the throttle speed and overcome the valve vibration. Moreover, the restriction orifice plate can also change the natural frequency of the system to avoid vibration caused by the natural frequency of the control valve close to the natural frequency of the system.
As one of the opening and closing devices, the pneumatic actuator installed in the valve has the function of using compressed gas to push the piston to make the valve stem connected with it play a role in driving the ball valve ball to move, thus playing the role of regulating the fluid medium in the pipeline. As one of the opening and closing parts, the ball rotates around the axis of the ball valve, which has a certain effect on the transmission of medium. The ball valve is characterized by wear resistance, good sealing performance, and due to the small resistance, the internal valve body is less worn and has a longer service life. This feature makes this kind of pneumatic valve more "handy" in the use of the pipeline.