Instrument working principle of the pneumatic valve

instrument pneumatic valve is a kind of pipe accessories, is now widely used in the control of conveying water, oil and gas in the dielectric fluid, such as highly attention in the market. So how instrument pneumatic valve works, works?
instrument working principle of the pneumatic valve
instrument pneumatic valve adopts analog signal controller, also called simulation instrument pneumatic valve. It identifies the simulation of controlled object parameters form the deviation of measured value with the given value, and according to certain regulation law an analog output signal drive actuators to eliminate bias, keep controlled parameters in the vicinity of a given value or a predetermined rule changes. In the automation instrument, instrument pneumatic valve is often used in the output signal of the examination instrument comprehensively in order to achieve the purpose of control the production process. By adjusting the parameters including temperature, pressure, flow, liquid level, composition, etc.