The basic introduction of pneumatic control valve

Pneumatic control valve is called a control valve as literally means to control material of a kind of industrial equipment, the following to introduce its definition and basic data. Pneumatic control valve and control valve, in the field of industrial automation process control, by accepting conditioning control unit of the output control signal, from engine operation to change the medium flow rate, pressure, temperature, liquid level control of process parameters such as components. And valve general, the executing agency. If the trip characteristics of pneumatic control valve can be divided into straight stroke and stroke; By their ticket enforcement agencies use the power, pneumatic control valve can be divided into pneumatic, electric pneumatic control valve, hydraulic pneumatic - valve three; According to its functions and features are divided into linear features, such as percentage and parabolic characteristics of three. Pneumatic control valve applied to air, water, steam, all kinds of corrosive medium, mud, oil, etc. A number usually FV beginning. Pneumatic pneumatic control valve, pneumatic control valve commonly used classification: electric pneumatic control valve, hydraulic pneumatic valve, self-reliance type pneumatic control valve. Defined in the automatic control of modern factory, pneumatic control valve plays a very important role, the production of the factory depends on the correct allocation and control flow of the medium. These controls both the exchange of energy, pressure reducing, or is a simple container loading, will need some control elements to complete. Plays a role of variable resistance of the pneumatic control valve in the pipeline. It change process fluid pneumatic - valve turbulence scale or in manual pneumatic - valve laminar cases provide a pressure drop, pressure drop is caused by resistance change valve or 'friction'. The pressure to reduce process is often referred to as 'throttling'. For gas, it is close to isothermal adiabatic condition, deviation depends on the degree of non-ideal gas ( Joule Thomson effect) 。 Under the condition of the liquid pressure, which is turbulent or viscous friction consumption, both of which put pressure is converted into heat energy, lead to an elevated temperature slightly. Common control circuit includes three main parts, one part is sensitive element, it is usually a transmitter. It is a device used to measure the modulated process parameters, the parameters such as pressure, level, or temperature. The output of the transmitter was sent to adjust the instrument - — Regulator, it determines or expectations and the process parameters and to measure a given value deviation between the actual value, one by one, the correction signal is sent out to control element - — Pneumatic control valve. Valve to change the flow of the fluid, the process parameters to achieve the expectations. Pneumatic - valve to control valve series, the main function is to regulate parameters such as pressure, flow, temperature, medium is process control elements in the loop.