Pressure relief valve: (Throttle relief valve)
In this article, we will learn about Pressure Relief Valve. The pneumatic system is designed to operate at a specific pressure to suit normal working conditions. Pneumatic components such as the pipeline and the cylinder may break when system pressure is exerted above normal working pressure. To avoid this, we need to ensure that the system pressure is above normal working pressure and that the equipment used is a pressure relief valve.
The setting of the spring-loaded type pressure relief valve is shown. They are usually used to discharge excess pressure when the system needs it. The main components are:
1. Valve body
2. Ball
3. Spring
4. Adjustable screw.
The Valve body consists of inlet and outlet ports. A ball operated by the inlet port spring key sits at the top of the inlet hole. Adjust the spring tension by adjusting the adjustable screw to suit working pressure. The inlet port is connected to the pipeline to control the Pressure. The outlet port will connect to the atmosphere.
In normal working conditions, the spring’s downward force is set to be greater than the upward force of the system pressure. In this way, the ball will hold its seat. Guirsi, for some reason, can block the airway and increase the normal working pressure system pressure.
At that point, the ball compresses the spring and moves from its seat upwards. So the valve opens and sends excess air into the atmosphere. Whenever the system returns to normal pressure, the ball will return to its normal position and the valve will return. Thus, this valve is used as a safety tool in the pneumatic system. It is fitted with a public vehicle pump.
Pressure Reducing Valve:
More than one actuator is sometimes used in a pneumatic system. Where pressure is less than the main system pressure to operate an actuator, a pressure demanding valve is used. These valves rely on the inlet port and provide uniform pressure on the outlet port. Depending on the type of pressure controlled, these can be divided into the following.
1. Diaphragm type pressure reducing valve.
2. Piston type pressure demanding valve.
Diaphragm type pressure demanding valve is shown. It consists of a valve, inlet, and outlet holes. The poppet is located between the inlet and the outlet, reducing or increasing the size of the airflow hole. In normal working pressure, the springs are horizontal as shown in the diaphragm by the downward force.
A small pilot passage is created between the outlet and the diaphragm. It is usually open when the system is running. When the outlet port system pressure rises above the already determined pressure, the diaphragm bends upward through the air entering the diaphragm area through the pilot passage. Because the poppet is attached to the diaphragm, the poppet also moves upward and reduces the size of the airway. Thus the system returns to the pressure already determined in the outlet.
The system of the piston type pressure demanding valve is shown. When the system exerts more pressure than normal working pressure, the spring at the top of the piston compresses and the piston moves upwards. So that the air passage is slightly obstructed. Therefore the outlet port pressure returns to its old working pressure. The valve then sends uniform pressure air to the pneumatic system.
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