Such an element of pipe fittings as an overpressure relief valve serves to protect the system from deformation as a result of exposure to excessive pressure in it. The design of the device provides for automatic bleeding of excess into the atmosphere.
Features
The device in question is used in pipelines to prevent emergencies and to regulate the pressure in working systems. The pressure in the pipelines can increase during operation above normal as a result of temperature changes or increased discharge during pump operation. In such cases, the overpressure relief valve performs its main function - it dumps the excess, normalizing its indicator in heating, plumbing or other systems.
Device
The design includes a pre-valve spring-type mechanism. The main working element of this unit is a tightly compressed spring. Its force locks the device and prevents the working medium from passing through the overpressure relief valve in the opposite direction. The response pressure is set taking into account the compression power of the spring.
You can adjust this indicator with the help of a special screw, which is equipped with all pressure relief valves for the water heater and their analogues. By turning the screw left or right, the desired degree of spring elasticity is achieved. Counterclockwise adjustment - unclenches the mechanism, reducing the rate of opening pressure. The process in the opposite direction, respectively, increases the compression of the spring to open.
Turbine: overpressure relief valve
Turbine pre-valve is part of directional valves. The operation of an element depends on the impact of a functioning environment. Excessive pressure may occur for the following reasons:
- Violation of the operation of turbine equipment.
- The presence of heat from extraneous sources.
- Incorrectly assembled trunk.
Overpressure relief valve is used in various industrial fields. The product is popular due to its simplicity of design and high reliability.
Analogs
The pre-valve for gas installations is equipped with a special shut-off element that opens when pressure is released inside the system.
For a water heater, the overpressure relief valve has a shut-off element and a setpoint. Both elements act on a sensitive membrane that aggregates with a locking device.
Another common analogue of the PSK type is structurally made so that the adjuster, through the spool force, facilitates the pressing of the locking element to the saddle. Thus, when the emergency valve is closed, the working pressure of the medium acts on the element located near the heating system.
Kinds
To prevent the formation of excessive pressure in the system, two types of devices are used:
- Elements of direct action. Most often they are used in fuel and oil systems. A part reacts to opening only when it is exposed to internal pressure.
- Indirect pressure relief valves. Such devices include devices used in liquid and air systems. All of these locking devices are divided into three classes, which differ in the principle of operation and internal equipment.
Spring mechanisms
In such devices, the spool is pressurized by compressing the spring. One element can undergo various adjustments by changing different types of springs.
Certain modifications are available with a built-in lever for manual override. This function allows you to purge the XFID (overpressure relief valve) in mechanical mode to control overall performance. The models under consideration mainly interact with aggressive substances. In this regard, the springs are equipped with a special protective coating, the stem seal is not provided, but there is an oil seal. The devices are equipped with a bellows type sealant, which is used if leakage of substance from the system to the outside is unacceptable.
Handle option
This type of water overpressure relief valve works according to the principle of direct action of the load directly on the spool that responds to pressure. The applied force travels the distance from the lever to the fixture stem. The adjustment of this type of valves involves a strong fixation of the load using the lever arm.
To ensure the absolute tightness of the seats with a larger diameter, weights with a large weight are used, which can cause a noticeable vibration of the whole mechanism. In such cases, operate the body with a pair of parallel saddles. In addition, two shutters, also working in parallel, are mounted in the skeleton. This design helps to reduce the weight of the load and the length of the levers. This, in turn, allows you to increase the speed of the device.
Magnetic spring modifications
This overpressure relief valve operates with an electromagnetic actuator. The element does not belong to the category of direct acting valves. Electromagnetic elements in the design allow you to strengthen the pressure of the spool and seat.
When pressure is triggered by an impulse coming from the sensors, an electromagnet is activated. In the future, only the spring exerts pressure resistance, and the valve functions according to the principle of a conventional spring mechanism. The existing electromagnet is able to create the force required to open, resisting the spring, after which the device is forced to open. There are modifications of air overpressure relief valves for compressors, on which the electromagnet performs enhanced compression, and the spring serves as a safety net, works when an unexpected power failure occurs.
CSID 0 5 600
Below is the device and the principle of operation of this element. The valve consists of the following elements:
- Housings.
- Damper fixed by a removable bracket during transport.
- Axles with bearings.
- The sealant responsible for sealing.
- An output flange that connects to the enclosure using gaskets and fasteners.
The pressure relief valve XCID 0 5 600 works according to the following principle:
- The shutter of the mechanism opens when excessive gas pressure is reached in the room.
- Excess medium is discharged into the atmosphere.
- After normalization of the pressure indicators, the damper returns to the seat with the specified tightness.
Overpressure Relief Valve: KamAZ
As such, a pressure regulator type 15.3512010 is used. Below are its characteristics:
- The difference in the adjustment of the output pressure indicators is 0.65-0.82 MPa.
- Response pressure - 0.94-1.0 MPa.
- The diameter of the internal / external connecting threads is M 22 * 1.5 / 16 * 1.5.
- Temperature operating conditions - from +60 to - 45 ° C.
- Weight - 600 g.
The principle of operation of this valve is the supply of compressed air from the compressor to the output of the regulator and through the receiver into the pneumatic system. Upon reaching a pressure of more than 0.6 MPa, the follower piston overcomes the force of the spring and rises. The valve seat moves away from the end of the cuff, and compressed air is supplied to the working cavity, moving the condensate drain valve, after which the air enters the atmosphere.