For the troubleshooting of pneumatic valve actuators, we will choose the most suitable pneumatic actuator. The pneumatic actuator with a high cost performance, then we must first understand the type of actuator. The actuator can be divided into pneumatic actuators and electric actuators, which are more commonly used. Actuators are these two, we will choose pneumatic actuators when we buy.
Then we need to choose the actuator according to the size of the air source. The torque required to turn the valve is too small to turn, and the valve life is not long if it is too large. Generally, it is OK to leave a 30% margin for torque. The pneumatic actuator can be seen from the text that this type of actuator is operated by air pressure. Compared with electric actuators, it can adapt to more environments, and the reasonable structure makes its load force greater, achieving the goal of high torque output. At the same time, compared to electric actuators, the action is faster and the response is faster. Of course, electric actuators also have many advantages that pneumatic actuators cannot match. The advantages of pneumatic actuators are also not available in current electric actuators. Both have their own shortcomings and advantages. Therefore, with continuous technology in the future, the cost performance of the two will be further improved.
Secondly, we evaluate the installed platform. Each environment chooses the actuator. There is a standard for the actuator. We will not be wrong if we find the corresponding standard according to the valve. As a pneumatic actuator, in fact, its role in the valve is to make the valve device more convenient when it is used. Due to the access of the pneumatic actuator, this valve can drive the rapid interlocking of the valve body components when operating in the pipeline, which has a certain automation effect, and because the actuator itself is driven by energy, so for the valve The drive of the valve body opening and closing parts is also of certain value. This kind of valve is used in the fluid pipeline to open and close due to low fluid resistance.
Common failures include the valve body does not move, the valve cannot be closed to zero position, the pneumatic actuator has no feedback signal, and the signal pressure is unstable. There are also some special faults, such as the vibration of the control valve of the pneumatic actuator. Next, we mainly analyze the causes of special fault control valve vibration and treatment measures.
Pneumatic valve actuator fault resolution
Pneumatic actuator control valve vibration will cause the control system to not work properly. The main causes of vibration are the following three:
1. External vibration source, that is, the equipment pipe itself has vibration.
2. The selection of the pneumatic actuator control valve does not meet the requirements of type selection, such as unsuitable flow characteristics, large valve diameter, poor spring rigidity, etc., causing the control valve to vibrate.
3. Vibration caused by fluid erosion.
Pneumatic valve actuator fault resolution measures: If it is found that the equipment pipe itself has vibration, the equipment pipe can be cleaned and readjusted to make the vibration disappear. If it is a problem with the control valve of the pneumatic actuator, the restrictor orifice plate can be used to absorb part of the pressure drop, reduce the throttle speed, and overcome the valve vibration, and the restrictor orifice plate can also change the natural frequency of the system to avoid the control valve natural frequency and The natural frequencies of the system are close to each other and generate vibration.
As the opening and closing device, the pneumatic actuator installed in this valve uses compressed gas to push the piston to make the valve stem connected to the valve function, driving the ball valve ball to move, thereby adjusting the pipeline fluid medium effect. As an opening/closing part, the ball rotates around the axis of the ball valve, which has a certain effect on the transportation of the medium. The characteristics of the ball valve are wear resistance and good sealing performance, and due to the low resistance, the internal valve body is subject to less wear and a longer service life. This feature makes this pneumatic valve more useable in pipelines." Handy".
