Valve definition

Valve definition: In the fluid system, used to control the fluid direction, pressure, flow device. Valves are devices that allow the flow and stop of the media (liquid, gas, powder) in the piping and equipment and control their flow. Valves are devices that allow the flow and stop of the media (liquid, gas, powder) in the piping and equipment and control their flow. The valve is the control component in the pipeline fluid delivery system. It is used to change the cross-section of the passage and the flow direction of the medium. The valve has the functions of diversion, cut-off, throttling, checkback, shunt or overflow pressure relief. For fluid control valves, from the simplest cut-off valve to a very sophisticated automatic control system used in a variety of valves, the variety and specifications of the valve nominal diameter from the very small instrument valve up to the diameter of 10m Industrial piping valves. The valve can be used to control the flow of various types of fluids such as water, steam, oil, gas, mud, various corrosive media, liquid metal and radioactive fluid. The working pressure of the valve can vary from 0.0013MPa to 1000MPa, working temperature From -269 ℃ ultra-low temperature to 1430 ℃ high temperature. Valve control can be used a variety of transmission methods, such as manual, electric, hydraulic, pneumatic, turbine, electromagnetic, electromagnetic, electro-hydraulic, pneumatic, spur gear, bevel gear drive, etc .; can pressure, temperature Or other forms of sensing signal, according to the predetermined requirements, or do not rely on the sensing signal for a simple open or close, the valve rely on the drive or automatic mechanism so that the hoist for lifting, sliding, swinging or turning Movement, thereby changing the size of its flow area in order to achieve its control functions.