A butterfly valve is a type of quarter turn valve. A quarter turn valve can open or close whenever the handle is turned 90 degrees (a quarter of a turn). The main function of these valves is to control the flow of liquids through a section of pipe. Butterfly valves are mainly used in waste treatment systems. They are extremely durable and need minimal maintenance.
Butterfly valves operate like other quarter turn valves. Understanding the way a basic butterfly valve works is pretty simple. It can help you to learn more about the components of valves.
Butterfly valves are made of a number of components. The most important one is the metal disc. This metal disc is the one commonly referred to as the butterfly. The butterfly is mounted on a rod and when the valve is closed it blocks passage of fluid. When the valve is fully open, the metal disc or butterfly moves a quarter turn. The passageway is unrestricted allowing fluids or air to pass.
In essence, the movement of the disc will depend on whether the valve is open or closed either partially or completely. If the valve is opened partially, it means that the disc will not be rotated a full one quarter turn, thus it cannot provide unrestricted passage. This means that, smaller amounts of fluid or air will pass through. However, if the valve is opened completely, the disc will be rotated 90 degrees then larger amounts of air or fluid will pass through.
There are many other components that form the butterfly valve. They include the resilient seat, body, packing, a stem and an actuator. The resilient seat is mounted on the body of the butterfly valve in order to provide the proper seal. The packing provides an additional seal especially in case the resilient seat is damaged.
Butterfly valves are configured differently. There are some which operate manually whereas others operate electronically depending on the system. They also come in different styles. There are those which offer high performance in systems like large pump lines and front suctions.
Butterfly vales can also be used in automobile systems. For instance, you will find the butterfly valve inside the carburetor of a car. In this case, the valve is used to control the flow of air to the car’s engine. It can partially open and close to regulate the amount of air passing through.