LFXD American Standard Series Pilot Safety Valves

Product introduction：

performance

Setting Pressure Deviation: <3%

Overpressure: <10%

Open-close differential pressure: <10%

Sealing performance: After take-off and return to the seat, it can maintain good sealability and meet the requirements of API Std 527 standard.


Characteristic

1. Soft seating ensures good sealability before and after take-off of safety valve.

2. Allow the working pressure to approach the setting pressure of the safety valve.

3. A small overpressure can make the main valve fully open quickly.

4. The operating performance and opening height of safety valve are not affected by back pressure.

5. Open-close differential pressure is adjustable.

6. The design of non-flowing guide valve structure reduces the discharge of harmful medium and environmental pollution.

7. The setting pressure of the safety valve can be measured online.


Working principle

When the system works normally and the pilot valve is closed, the system pressure passes through the inlet pressure pipe, the pilot valve and the chamber pressure pipe to the top of the main valve disc, which generates a downward net force on the main valve disc and makes the main valve closed.

When the system pressure reaches the set pressure, the guide valve opens and the sliding shuttle closes the intake passage of the guide valve. The pressure of the main valve chamber releases pressure through the guide valve. Because the system pressure is higher than the return pressure, the sliding shuttle closes the intake passage to block the flow of fluid in the guide valve (the characteristics of the non-flow guide valve). At this time, the pressure of the main valve chamber drops sharply, the main valve disc opens completely, and the flow is through. Discharge and reduce pressure through main valve.

When the system pressure decreases to a certain value, the spring force of the guide valve overcomes the force acting on the slide shuttle by the inlet pressure of the valve. The guide valve returns to its seat and the top of the ejector rod opens the slide shuttle. Finally, the fluid enters the dome chamber of the main valve and closes the main valve.