The regulating valve medium generates a force on the detection element that is balanced with the pre tightening force of the preset spring. When the pressure inside the tank rises above the pressure set point of the nitrogen relief device, the balance is disrupted, causing the valve core to move up and open the valve to release nitrogen to the outside world; When the pressure inside the tank drops to the pressure set point of the nitrogen relief device, the valve is closed due to the preset spring force.

Positioners will be used in the application of regulating valves, and the locators used can be divided into ordinary locators and intelligent locators. Ordinary positioners work using mechanical force balance principle, namely nozzle baffle technology. There are mainly the following types of faults: due to the use of mechanical force balance principle, there are many movable components, which are easily affected by temperature and vibration, causing fluctuations in the regulating valve. Therefore, nozzle baffle technology is used.

Due to the small size of the nozzle hole, it is easy to be blocked by dust or a clean air source without the diaphragm valve, causing the locator to malfunction. Using the principle of force balance, the elastic coefficient of the spring changes under harsh conditions, causing nonlinearity in the control valve and resulting in a decrease in control quality.