A butterfly valve is a quarter-turn valve that resembles the properties and format that are much similar to that of the Ball valve family. It carries out the functions of starting, regulating and stopping the flow of fluids within a system.
When you have a closer look at the butterfly control valve, you will be able to notice that the disk of the valve is connected to the rod. Because of this structure, it resembles the shape of a butterfly, and that is why it gets its name as the “butterfly control valve”.
Construction of butterfly control valves
The disk, the body, the stem and the seat are the four major components of the butterfly control valve.
- The body: The body of the butterfly valve is designed in such a way that it can easily fit between the two pipe flanges. The butterfly valves can have either of the two types of body designs,
- Lug body design
- Wafer body design
- Disk: The disk of the valve determines how the fluid flow stops in a system. It performs the function that is equivalent to the ball, gate and plugs in the ball, gate and plug valves respectively.
- Stem: There can be 2 types of stem designs in a butterfly valve.
- A one-piece shaft or single stem
- A two-piece shaft or split stem
- Seat: The seat provides a shutoff to the valve. It can either be permanently attached to the body of the valve, or it can be having a lockable system that allows pressing of the seat when not in use.
- Easy to operate and fast to open.
- The handle is designed in such a way that it can have a 90-degree rotation to allow smooth opening and complete closure of the valve.
- The larger butterfly valves come with an added gearbox that simplifies its operation. The only drawback of this is the reduced speed.
- They are comparatively much lighter in weight and occupy lesser space when compared to the ball, gate and plug type of valves.
- Reduced and cost-efficient maintenance expenses.
- They are available in very large sizes.
Different industries and sectors make the use of butterfly control valves in different ways and manners.
- Switch on and switch off modulating services
- Vacuum service
- For industries where the flow of large amounts of slurry needs to be regulated.
Moreover, it can also be utilised in fire protection, cooling water, and chemical and oil industries.