The reason for automatic closing of Self-actuated control valve

Differential pressure control: When the pressure difference ΔP before and after the valve is less than the set pressure difference ΔPs, the self operated control valve will continue to remain closed. This is because if the pressure difference is not enough to overcome the elastic force of the spring, the pressure sensing film cannot drive the valve plug to rise, and therefore the valve cannot open. ‌

System operating condition change: If the system operating condition changes and the inlet and outlet pressure difference ΔP is less than the set pressure difference ΔPs, the valve will close and the flow rate will decrease to reach a new equilibrium state. If this situation persists, the valve will eventually close completely. ‌

Installation and operation errors: If the installation position of the self operated control valve is incorrect, or if the installation error is caused by a low-quality installation team or a weak sense of work responsibility, it may also lead to valve adjustment failure and automatic closure. ‌

Water quality issue: If the water quality in the pipeline network is poor and contains a large amount of impurities and floating debris, these impurities may clog the valve disc, causing the valve to fail to adjust properly and potentially closing automatically. ‌

Design and usage issues: Installing self operated control valves at the end of the heating system may increase local resistance, thereby affecting flow distribution. If not designed or used properly, it may result in a decrease in incoming flow, affecting heating efficiency, and even causing the valves to automatically close. ‌

Valve blockage: When the self regulating valve works normally, the gap between the valve core and the valve seat is small, which is easily blocked by impurities or oxides, hindering the normal operation of the valve. Therefore, valve blockage is also a major reason for the sudden closure of self regulating valves.

Sudden change in water supply pressure: The self regulating valve adjusts the opening of the water valve with changes in water flow rate and pressure during operation. But if there is a sudden change in water supply pressure, such as a water pipe burst or unstable water supply pipeline, the self operated regulating valve may close in a short period of time.

Control system failure: Self operated regulating valves usually work under the action of signals such as measurement, feedback, and commands. If the control system fails, it will affect the opening and closing of the valve. For example, damage to the electromagnet, sensor failure, and other reasons may cause the self operated regulating valve to suddenly close.

resolvent:

1. Regularly clean and maintain the self regulating valve to improve water quality and prevent debris from entering the valve.

2. Install voltage stabilizers and other equipment to stabilize water pressure and avoid sudden pressure changes.

3. Regularly check the status of the control system to ensure its normal operation. Meanwhile, a backup control system is also essential for emergency use.

The above are possible reasons and solutions for the sudden closure of the self regulating valve. To avoid these problems, it is necessary to regularly maintain, clean, and inspect the valves. Meanwhile, pay attention to the stability of water quality and pressure to ensure the normal operation of the self regulating valve. In summary, the reasons for the automatic closure of self operated control valves may be multifaceted, including pressure differential control within the system, external installation and usage conditions, and water quality issues. Understanding these reasons can help take corresponding measures to prevent and solve this problem. ‌