What is a Butterfly Valve?
A butterfly valve is a type of flow control valve used to regulate the flow of gases or liquids. They can be either manual or automated, and they are often used in HVAC systems as well as industrial water systems.Butterfly valves are so named because the disc that controls the flow of the valve resembles the wings of a butterfly. They have several advantages over other types of valves, including a large flow range, a high degree of shutoff, low pressure drop, and a minimal backpressure. Butterfly valves are often used when it is important to keep the flow rate low, as in large home water systems or commercial refrigeration systems.Butterfly valves are used in many different applications, but they are most common in water systems. They are often used as the terminating device on water lines. The main advantage of a butterfly valve over other types of valves is that it is easy to install and does not require much maintenance.
How Does a Butterfly Valve Work?
The butterfly valve’s pivoting disc is controlled by the pressure difference between two sides of the disc. When the disc is fully opened, it allows full flow from one side to the other. When the disc is fully closed, it stops all flow. In between those two extremes, the disc is “balanced” so that the pressure on each side of the disc is the same. That allows you to control the flow on one side while maintaining full flow on the other.The pressure difference is created by either air pressure or liquid pressure. If you create air pressure on one side of the disc and apply water pressure on the other side (or vice versa), the disc will move to the side with the higher pressure.
Installing a Butterfly Valve
The first step in installing a butterfly valve is to identify the correct location for the valve in the water system. Once you have identified the desired water flow path, you need to make sure that you have selected the correct diameter size for your water line.In general, the diameter of a water line should be at least 2 times larger than the diameter of the flow that it is carrying.Once you have identified the proper size for your water line, the next step is to thread the pipe and install the butterfly valve. Most butterfly valves have nuts on either end of the valve to allow you to connect the valve to either side of the water line.Once you have the butterfly valve connected to either side of the water line, you can adjust the valve to the correct position so that the flow is being controlled properly in each direction.
Other Considerations When Installing a Butterfly Valve
Butterfly valves rarely need to be replaced. However, you will need to keep them in good condition by regularly cleaning the valve and making sure that the nut connections are kept tight. You should also inspect the valve regularly for any signs of damage or wear.If you are controlling water flow with a butterfly valve, make sure to install the valve downstream from all fixtures (sinks, showers, etc.) that are controlled by the valve. That way, the pressure is being reduced before it travels back to each fixture.If you plan on using air pressure to control the butterfly valve, make sure to install the valve downstream from any air pressure source so that the air pressure being applied to the valve travels down the water line before reaching any other device.If you are installing a butterfly valve on a water line that has a significant back pressure, you may want to consider installing an unbalanced butterfly valve on one side of the line.
Conclusion
The butterfly valve is a pressure-controlled valve equipped with a balanced pivoting disc that opens and closes like the wings of a butterfly. These valves are available in two main designs: Unbalanced Butterfly Valve and Balanced Butterfly Valve. Both have their own benefits and applications, but for most industrial water systems, the Balanced Butterfly Valve is the better choice. The pressure difference is created by either air pressure or liquid pressure, and the disc is controlled by the pressure difference between two sides of the disc. The main advantage of a butterfly valve over other types of valves is that it is easy to install and does not require much maintenance. Butterfly valves rarely need to be replaced, but you will need to keep them in good condition by regularly cleaning the valve and making sure that the nut connections are kept tight. If you are controlling water flow with a butterfly valve, make sure to install the valve downstream from all fixtures (sinks, showers, etc.) that are controlled by the valve. If you plan on using air pressure to control the butterfly valve, make sure to install the valve downstream from any air pressure source so that the air pressure being applied to the valve travels down the water line before reaching any other device.
