Safety valve When the pressure of the container exceeds the design specification, the safety valve opens automatically, and the exhaust gas reduces the excessive pressure in the device to prevent the damage of the container or pipeline.
When the pressure inside the vessel drops to normal operating pressure, it automatically shuts down to avoid all the gas being exhausted due to the overpressure of the vessel, resulting in waste and production interruption. The safety valve is mainly composed of three parts: valve seat, valve disc (valve core) and loading mechanism.
Some valve seats are integrated with the valve body, and some are assembled with the valve body, which communicates with the equipment. The valve disc is often associated with a valve stem, which is tightly fastened to the valve seat. Above the disc is a loading mechanism, and the size of the load can be adjusted.
When the pressure in the equipment is within a certain working pressure range, the force of the internal medium acting on the valve disc is less than the force applied by the loading mechanism on the valve, and the difference between the two constitutes the pressure between the valve disc and the valve seat. The sealing force makes the valve disc press the valve seat tightly, and the medium of the equipment cannot be discharged.
When the pressure in the equipment exceeds the specified working pressure and reaches the opening pressure of the safety valve, the force of the internal medium acting on the disc is greater than the force exerted by the loading mechanism on it, so the disc leaves the valve seat and the safety valve When it is opened, the medium in the equipment is discharged through the valve seat. If the displacement of the safety valve is greater than the safe discharge amount of the equipment, the pressure in the equipment will gradually decrease, and after a short period of exhaust, the pressure will return to the normal working pressure.
At this time, the force of the internal pressure acting on the valve disc is smaller than the force exerted by the loading mechanism on it, the valve disc presses the valve seat tightly, the medium stops discharging, and the equipment keeps running at normal working pressure.
Therefore, the safety valve is closed or opened by itself to prevent the overpressure of the equipment through the fluctuation of the medium force on the valve disc and the force of the loading mechanism.
