Working principle of pressure reducing valve
The core working principle of a pressure reducing valve is based on the principle of force balance, which automatically adjusts the valve opening by sensing changes in outlet pressure. The following is a detailed analysis of its working process:
1. Basic components
-Valve body: an outer shell that accommodates all internal components
-Valve disc: a moving component that controls the passage of fluid
-Spring: a force source that provides preset pressure
-Diaphragm/piston: a sensitive component that senses pressure changes
-Adjusting screw: used to set the desired outlet pressure
2. Detailed explanation of the work process
Initial state: The spring pushes the valve disc away from the valve seat through pre compression force, and the valve is in the open state.
Pressure establishment: The fluid enters the downstream system through an open valve, and the outlet pressure gradually increases.
Feedback effect: The rising outlet pressure acts below the diaphragm or piston, generating an upward force.
Force balance: When the upward force generated by the outlet pressure is equal to the downward force of the spring, the system reaches balance and the valve remains partially open.
Pressure regulation:
-When the downstream pressure increases (such as a decrease in water consumption), the thrust on the diaphragm increases, pushing the valve disc to move in the closing direction, reducing the flow rate and thus lowering the pressure.
-When the downstream pressure decreases (such as an increase in water usage), the spring force dominates, pushing the valve disc further open, increasing flow and pressure.
Steady state: Through this dynamic adjustment, the outlet pressure is maintained near the set value, with fluctuations typically controlled within ± 10%.
3. Key characteristics
-Proportional control: Most pressure reducing valves use proportional control instead of switch control for smoother regulation
-No need for external energy: using the system's own pressure as a power source
-Automatic response: The response time to pressure changes is usually completed within a few seconds
