Automated Valve And Control: A Selection Process

When it comes to the different types of automated control valves, there is a large selection to choose from. There are pressure-reducing valves, flow control valves, back-pressure sustaining valves, altitude valves, and relief valves, just to name a few.

Automated valve and control processes are not difficult to figure out. Start with the type of valve you are looking for. As a part of that process you should also determine your valve's size.

There is an intimate relationship between flow processes and the components of the control valve. This is by design. In most cases, the way your valve is made determines how the flow of liquid proceeds through the valve and the other components of your system, you'll need to ensure that you choose the right valve. Otherwise, your automated valve and control process can produce undesirable results.

Measure the ratio between liquid flow and the control change percentage. Also, measure the distortion in valve characteristics as well as rangeability. Finally, make sure you measure the difference in ratio between maximum and minimum controllable flow.

Gain and stability are very important in these measurements. To determine gain, divide valve flow output by input. If your gain is constant, then you have a linear valve flow.

The Different Types Of Automated Valve And Control

There are three primary ways that liquid flow is produced in your valve components.

Electrical valve flow is produced, naturally, through electrical impulses. Hydraulic valve flow involves mechanical signals that are caused by fluid pressure. Pneumatic valve control is caused by the conversion of energy into mechanical pressure.

Slurry Valves And Automated Valve And Control Processes

When it comes to slurry valves, there are many different processes and types of valves that come into play.

For the most part, diaphragm valves are superior to pinch valves. However, if your pressure is low, then you'll want to go with pinch automated valve and control. If you are facing corrosion-resistance, then go with the diaphragm valve.

Butterfly valves are best when your pressure is high and valve drop is low.

To produce optimal rangeability, use small and constant valves. Pay very close attention to orifice size, particle size, and rangeability when choosing slurry valves.

The best valves are valves that, when open, provide full pipeline opening. What you want is a streamlined flow path during throttling with high pressure and temperature conditions. Self-draining valves are also preferred. If possible, ensure the actuator stem is sealed off from the flow process.

Three Parts Of Automatic Valve Control Devices

In recent years, automated valve and control processes have adopted smart methods, which make the flow process smoother and easier to measure. But whether the smart method is used or the old-fashioned valve control systems, there are three main parts of the control valve to be familiar with.

Control valves generally have an actuator and a positioner. Then there's the main body part of the valve.

The purpose of the actuator is to locate the valve plug once it responds to the control signal. The positioner is often attached to the actuator and linked to the spindle. Its purpose is to monitor the valve position.

Being familiar with the components of valve control devices will make it easier for you to diagnose and correct problems.