Pilot Operated Safety Valve
The pilot-operated safety valve co-brand YOY Yongyi Valve Group designed by Dazhong Valve Group, the pilot-operated safety valve, also known as the pulse-type safety valve, is a kind of safety valve that relies on the medium discharged from the pilot valve to drive or control the main valve. The valve itself is a standard spring direct loaded safety valve. According to the structure, it can be divided into vertical hammer type, lever type, spring type and pilot type pulse type. The pilot type safety valve has good sealing performance, and at the same time, its action is rarely affected by back pressure.
The pilot-operated safety valve is suitable for high pressure and large-diameter applications. The pilot-operated safety valve has good sealing performance, and at the same time, its action is rarely affected by back pressure. The disadvantage of this safety valve is that its The reliability is related to the main valve and pilot valve, the action is not as fast and reliable as the direct-acting safety valve, and the structure is more complicated.
When the system pressure drops to a certain value, the valve core of the pilot valve will be seated downward under the action of the spring, the sealing surface of the pilot valve will be closed, the spool valve of the valve cavity of the pilot valve will be opened, the valve cavity will be unblocked, and the system pressure will be restored again. It is introduced into the air chamber above the main valve disc through the pilot valve cavity, and pushes the main valve disc to close.
When the system pressure rises to the set pressure, the gas pushes up the spool of the pilot valve at the sealing surface of the pilot valve, so that the sealing surface is in an open state, and at the same time, the spool valve in the valve cavity of the pilot valve moves upward, Close the air passage of the pilot valve cavity. The medium in the air chamber above the main valve disc is discharged through the open pilot valve sealing surface, so that the pressure above the main valve disc is reduced. The main valve disc is pushed by the inlet pressure to open and make System depressurized.
