Does The Brass Valve Positioner Function

The valve positioner is the main accessory of the control valve. It uses the valve stem displacement signal as the input feedback measurement signal and the controller output signal as the set signal for comparison. When there is a deviation between the two, the output to the actuator is changed. The signal causes the actuator to move, establishing a one-to-one correspondence between the displacement of the valve stem and the output signal of the controller. Next, I will introduce the role of the electric valve positioner.

1. The electric valve positioner is an adjustment system with high requirements for adjustment quality, and it is necessary to improve the positioning accuracy and reliability of the adjustment valve.

2. The installation is where the pressure difference across the valve is greater than 1 MPa. By increasing the air pressure, the output force of the starter is increased, overcoming the different force generated by the fluid on the spool and reducing the error in the stroke.

3. In order to avoid external leakage, when the flowing fluid contains high temperature, high pressure, low temperature, toxic, flammable, explosive, etc., the filler is usually squeezed very tightly. Increase, then use the positioner to overcome the time lag.

4. When the fluid is a viscous fluid or contains solid suspended solids, the use of a positioner can reduce the resistance of the fluid to the movement of the valve stem.

5. The positioner is also capable of overcoming the transmission lag of the control signal and improving the reaction speed of the valve.

6. Improve the flow characteristics of the regulating valve.

7. When a single regulator controls two actuators, two positioners can be used, with one low-level action and the other high-level action. Receiving low input signal and high input signal respectively, to achieve split-range adjustment status.