Quick Pressure Relief Valve (QPR)
The Pressure Relief Valve is a piloted hydraulic valve activated by line pressure. The 2-way pilot has a spring-loaded diaphragm that is sensitive to upstream pressure. The valve is normally closed. As the line pressure rises above the preset level, the valve opens quickly to relieve the excess pressure.
A Quick Pressure Relief Valve (QPR) protects water systems from rapidly increasing excess pressure. It is recommended to install the Ooval QPR valve at the start of the system near the main supply line or booster pump.
The valve is a general application 2-way piloted Pressure Relief Valve with a pressure rating up to 232 PSI (16 bars).
The Pressure Relief Valve is activated by line pressure. The displacement of the diaphragm in the pilot is due to a rise in line pressure against the spring force. As the pressure increases above the set point, the water flow inside the pilot is directed so that the valve quickly opens.
Automatic: When the line pressure is low, the sustaining pilot and the valve are closed by line pressure. The valve remains closed until the line pressure is higher than the set point of the pilot. As pressure increases above the set point, the diaphragm moves upward under the line pressure and port 5 (outlet downstream) of the pilot opens, allowing the control chamber to drain through the vent. The valve opens in a few seconds relieving the excess pressure.