Working principle and application of YFA72W vacuum safety valve
date:2024-05-28 09:40
YFA72W vacuum safety valve, also known as vacuum negative pressure safety valve, has two categories: spring type and rod type. In addition, there are impulse safety valves, pilot safety valves, safety switching valves, safety relief valves, static weight safety valves, etc. Spring type safety valves mainly rely on the force of springs to work. Spring type safety valves have both closed and unclosed types. Generally, closed type should be used for flammable, explosive or toxic media, and unclosed type can be used for steam or inert gases. Spring type safety valves also have wrenches and non wrenches. The main function of a wrench is to check the flexibility of the valve disc, and sometimes it can also be used for manual emergency pressure relief.
The working principle of the type vacuum safety valve
The safety valve plays a safety protection role in the system. When the system pressure exceeds the specified value, the safety valve opens and releases a portion of the gas in the system into the atmosphere, ensuring that the system pressure does not exceed the allowable value, thereby ensuring that accidents do not occur due to excessive pressure. Safety valve, also known as relief valve. The diagram shows several typical structural forms of safety valves. For piston type safety valves, the valve core is a flat plate. The air source pressure acts on piston A. When the pressure exceeds the safety value determined by the spring force, piston A is pushed open, and a portion of compressed air is discharged into the atmosphere from the valve port; When the pressure of the air source is lower than the safe value, the spring drives the piston to move downwards and closes the valve port.
Figures b and c show ball valve and diaphragm type safety valves, respectively, with the same working principle as piston type. These three types of safety valves are all controlled by springs. By adjusting the pre tension force of the spring, the safety value can be changed, so they are called direct acting safety valves.
Figure d shows a pilot operated safety valve, which provides control pressure on the diaphragm through a small direct acting valve. The hard core on the diaphragm is the valve core, which is pressed against the valve seat. When the air source pressure A exceeds the safety pressure, the valve core opens and compressed air is discharged into the atmosphere from the left output hole. Diaphragm type safety valves and pilot type safety valves have good pressure characteristics and sensitive actions; However, the large opening force is relatively small, indicating poor flow characteristics. In practical application, the type of safety valve should be selected according to actual needs, and its diameter should be selected according to the large exhaust volume.
