Control valves are used extensively in a variety of industries to control the physical conditions such as flow, pressure, temperature and liquid level. Controlling these conditions are very important in the oil & gas and manufacturing industries to maintain the flow of materials within safety limits.
Sensors sense and measure conditions such as pressure and temperature; and microcontroller comparing the magnitude of them with a certain value. After the comparison, it sends appropriate control signal to open or close the control valve.
The previous control valve is opened or closed manually, but today almost every industry using automatic control valves. Apart from this, know more about the control valve via http://www.asia-pacifics.com/products_brand/Ace%20Valve.
Some types of control valves used in the industry, which vary in design and construction. Usually, the control valve has three main parts: valve actuators, valve positioners, and valve body.
The valve actuator: It is used to automatically open or close the valve, according to the control signal varies the flow of liquid.
Depending on the resource actuators, there are four main types of actuators: electrical actuators, hydraulic, electro-hydraulic actuators and pneumatic actuators. electric actuator has a motor that is driven by an electric current or voltage supply.
The actuator is easy to control, as an electrical signal can be easily managed by a microcontroller and amplifier. Hydraulic and pneumatic actuators are very similar in structure and contain a piston and cylinder arrangement.
In the case of hydraulic actuators, cylinders filled with water, while in the pneumatic, it is filled with air. An electro-hydraulic cylinder is a combination of electric and hydraulic cylinders and can drive heavier loads, and at the same time easily controlled by electrical signals.