Self-operated flow balancing valve is a kind of valve that uses the pressure change of the medium itself to control itself and keeps the flow rate unchanged through the controlled system of the valve, which has a flow indication and can be adjusted. A one-time adjustment before operation can automatically keep the system flow rate at the required set value.
The principle of self-operated flow balancing valve.
After the controlled medium is input into the control valve, the pressure P1 in front of the valve is input into the lower chamber of the diaphragm through the impulse pipe, the pressure P2 after throttling through the manual integral, enters the upper chamber of the diaphragm through the impulse hole on the automatic valve disc, the difference between P1 and P2 is P=P1-P2 is called the effective pressure, the thrust generated on the P1 acting diaphragm and the thrust generated on the P2 acting diaphragm are balanced with the spring reaction force, and the relative position of the automatic valve disc and the valve seat is determined, so as to determine the flow rate of the valve. When P=P1-P2 increases, the flow rate has a tendency to increase, the thrust generated on the diaphragm by P1 and the thrust generated on the P2 diaphragm are different, so that the automatic valve disc moves to the direction of the valve seat, thereby changing the flow area between the automatic valve disc and the valve seat, the resistance is increased, the P2 is increased, the flow rate is increased, the thrust of the increased P2 acting on the diaphragm plus the spring reaction force and the thrust acting on the diaphragm by P1 are balanced in the new position, and P is restored to the original value, and the purpose of controlling the flow rate is achieved. The opposite is true.
In the application process of self-operated flow balancing valves, there are some issues that need to be paid attention to. First of all, it is necessary to ensure the stability of the pressure p1 before the valve and the pressure p2 after the valve to avoid the influence of pressure fluctuations on the flow control. Secondly, the diaphragm and spring should be reasonably selected according to the actual needs to ensure the adjustment accuracy and service life of the valve. In addition, during use, the valve needs to be regularly inspected and maintained to ensure that it is working properly.
Overall, the self-balancing flow valve is a very practical valve that can effectively solve the problem of flow control in industrial pipelines. In the future, with the continuous improvement of industrial automation, the application prospect of self-operated flow balancing valve will be broader.