Pneumatic Control Valve Production Process
The implementation process of the pneumatic dispatch valve The process implemented by the pneumatic dispatch valve is the propulsion part of the actuator. It receives the air pressure signal output by the electric valve converter (or electric valve positioner) and converts it into the corresponding linear displacement of the push rod. , In order to promote the scheduling and organization of operations.
The process implemented by the pneumatic dispatch valve can be divided into several categories, such as membrane type, piston type, rolling diaphragm, and M-10. In the meantime, the first three types belong to the straight-stroke implementation organization, and their power components move linearly under the action of compressed air. The power components of the rotor to implement the organization rotate under the action of compressed air, which is a typical quarter-stroke pneumatic implement organization.
This kind of pneumatic dispatch valve is more commonly used. Its characteristics are simple structure, low price, reliable action and convenient maintenance; no valve positioner is needed, and the share action can be completed only by implementing the spring; when the air supply is stopped, the push rod It can actively return to the non-signal position, and it can be used with the valve to provide the source of safety for the production. But its output stroke is small and can only withstand lower air pressure for operation. Generally, the high air pressure is o.25-0.4MFa, which can only directly drive the valve stem. Therefore, it is mainly used as a propulsion device for general dispatching valves.
Pneumatic membrane implementation process can be divided into two types with spring and without spring, and there are two ways of action, positive action and reverse action. When the gas pressure in the membrane chamber increases, the active organization of the valve stem moving in the direction of extending out of the membrane chamber is the positive acting type, and the movement in the direction of late entering the membrane chamber is the counteracting type. The implementation organization of different action methods provides convenience for the two action methods of air opening and air closing for different types of valves. The diaphragm pneumatic implementation organizations used in practice are all types with implementation springs, and those without springs are rarely used.
