Flow characteristics of electric control valve

 Electric dispatch valve is an important implementation unit instrument in industrial automation process control. With the increasing degree of automation in the industrial field, electric dispatching valves are being used more and more in various industrial production fields. Electric dispatching valves generally include a driver, which accepts driver signals (0-10V or 4-20MA) to control the valve for dispatching. It can also form an intelligent network control system according to control requirements to optimize control and end long-distance monitoring.
 The flow characteristics of the electric dispatch valve have three types: linear characteristics, equal percentage characteristics and parabolic characteristics: equal percentage characteristics (logarithmic). The relative stroke and relative flow of equal percentage characteristics are not connected in a straight line, which is caused by the unit stroke change at each point of the stroke. The change in the flow rate is proportional to the flow rate at this point, and the percentage of the flow rate change is the same. Therefore, its benefit is that when the flow is small, the flow change is small, and when the flow is large, the flow change is large, that is, at different opening degrees, it has the same scheduling degree.
  Linear characteristic (linear) The relative stroke and relative flow of the linear characteristic are connected in a straight line. The flow change caused by the change of the unit stroke is unchanged. When the flow is large, the relative value of the flow changes little, and when the flow is small, the relative value of the flow changes more.
The parabolic characteristic flow rate changes in proportion to the two sides of the stroke, and generally has the central characteristic of linear and equal percentage characteristics. From the analysis of the above three characteristics, it can be seen that in terms of its scheduling function, the equal percentage characteristic is the best, its scheduling is stable and the scheduling function is good. The parabolic characteristic is better than the linear characteristic dispatch function, can choose any kind of flow characteristic among them according to the different requirements of the application occasion.