Function and structure principle of pneumatic pneumatic valve positioner

pneumatic pneumatic valve positioner is pneumatic regulating pneumatic valve is one of the important accessories and fittings. Pneumatic valve positioning effect.

pneumatic pneumatic valve positioner features:
pneumatic pneumatic valve positioner and actuator constitute control unit and a variety of regulating pneumatic valve connection after debugging installation, pneumatic regulating pneumatic valve.
used for various industrial automation of the process control field.

pneumatic pneumatic valve positioner structure principle:
pneumatic pneumatic valve positioner receives from the controller or control system to mA and other weak current signal, and sending air signal to pneumatic actuators to control the pneumatic valve position of the device.
with the pneumatic valve, pneumatic control constitute a closed loop control circuit. Converts the signal control system of dc current drive adjust the gas signal of pneumatic valve, pneumatic valve control actions. At the same time, according to the feedback to adjust the opening of pneumatic valve, pneumatic valve position can be according to the system output control signals for correct positioning.

pneumatic pneumatic valve positioner supporting:
can be used for single acting type ( Spring return type) And double-acting pneumatic actuators.

the working principle of pneumatic pneumatic valve positioner:
pneumatic pneumatic valve positioner is according to the principle of moment balance work, when the signal going into the corrugated pipe pressure P increases, turns the main lever fulcrum around, make the nozzle baffle near the nozzle, the nozzle back pressure after the one-way amplifier amplification, going into the chamber to actuator of film pressure increases, the pneumatic valve rod moves down. CAM drive feedback pole around the pivot and turn, feedback is a counterclockwise rotation, through the roller to rotate the vice lever fulcrum around, and will feedback the spring tension, tension of main lever spring and the force signal on the stress in the corrugated tube to moment balance, the balance. Actuator pneumatic valve position to maintain on a certain opening, certain signal pressure corresponds to the pneumatic valve position opening. Above action is positive effect, if you want to change the way we work, as long as will turn CAM, to become A to B, etc. , can. The so-called positive locator, is signal pressure increases, the output pressure also increased; The so-called reaction locator, is signal pressure increases, the output pressure is reduced. A positive role in executing agency as long as the mount reaction locator, can realize reaction actuator movement; Instead, a backlash actuators as long as the mount reaction locator, can achieve positive action of the actuator.