How Does a Butterfly Valve Work?
Butterfly valves are a regular part of any industry - whether in domestic or industrial conditions, butterfly valves serve a variety of purposes. There are several basic types of industrial valves such as butterfly valves, ball valves, check valves, etc. These are common in many industries.
Qualified industrial valve manufacturers specialize in the production of the various valves mentioned above. Butterfly valves are common industrial valves commonly used in waste management systems, oil and gas refineries, and more. This article discusses in detail what a butterfly valve is and how it works.
What Is a Butterfly Valve?
One of the commonly used industrial valves is the butterfly valve - a member of the quarter-turn valve family, which is commonly used to stop and start the flow of media in pipelines. While these valves can be used to regulate media flow, they are subject to serious damage and are not widely recommended.
Butterfly valves are quarter-turn valves, just like industrial ball valves - this means that when these valves are turned 90°, they either stop completely or allow the medium to flow. These valves are lightweight and compact due to their simple design. The valve can be fully closed or opened by turning it 90°, but in order to regulate the flow, the valve should not be fully turned.
Using a valve for adjustment may call its sealing performance into question. In addition, the disc is easily damaged when used for adjustment, so this type of valve is often used as an on-off valve. The advantages of using butterfly valves include fast actuation and lower cost.
There are many types of butterfly valves – triple eccentric butterfly valves, concentric butterfly valves, and high-performance butterfly valves are some of the common ones.
Butterfly Valve Parts
While most industrial valves share common parts, specific types of valves have unique parts and functions. Here are some common parts found in butterfly valves:
The valve body contains the different parts of the butterfly valve. There are two main types of valve bodies: wafer body and lug body.
Wafer body types are simple in design compared to lug body types - for connecting pipes, the body has bolt holes throughout the body. This body type is typically used in systems where backflow prevention is required but is not suitable for regulating systems.
On the other hand, the lug-style body in a butterfly valve is completely external to the pipe. Instead of holes in the valve body, this design has protruding lug holes on the outside. While this body type is slightly more complicated, it has its own advantages.
The butterfly plate is the part of the butterfly valve that is responsible for controlling the flow. It is attached to the valve body, similar to the structure of the gate valve in the gate valve. While there are many variations in disc design depending on its application, common variations include eccentric and concentric. For butterfly valves, it is essential to have a rigid disc to ensure precise throttling of flow.
The seat is the wave component that holds the disc in place - the valve's seat is made of a strong elastomer to ensure it does not move from its position. It should also be noted that the seat is not a small part of the butterfly valve, but rather a liner that runs through the valve. Elastomers are used to produce these parts because they help maintain a tight seal between the seat and the disc.
If the butterfly valve is manually driven, there should be a mechanism to connect it to the disc to throttle it. The stem or shaft is the unit that connects the actuator to the disc. There are two types of stems - wetting and non-wetting.
There are many seals inside the butterfly valve to ensure that the valve does not leak and closes tightly. Wrong sealing will cause fatal damage to the work of the butterfly valve, so it is an important part of the valve.
How Does a Butterfly Valve Work?
As mentioned earlier, butterfly valves are quarter-turn valves that are best suited for stopping/starting the flow of media in pipelines. When the valve handle is turned 90°, it is either fully open or fully closed. Throttling can be a bit difficult, but these valves can still be used for regulating purposes.
Butterfly valves can be operated manually, pneumatically, or electrically via actuators. Using an actuator can help control the valve - the actuator will be attached to the disc and it will move the disc according to the desired operation.
For each type of operation, there is a specific type of tool that can help perform it. For example, a pneumatically controlled butterfly valve has a piston attached to it. Technically, this is the best way to control a butterfly valve because of its quick closing and opening capabilities.
Butterfly valves are usually installed in the fully open position. This is because installing the valve in the closed position can cause difficulties with the seating and sealing position.
What Are Butterfly Valves Used For?
Butterfly valves are used specifically for fluid storage and transportation as these valves excel at handling media such as slurries. Butterfly valve manufacturers consider quality, technology, materials, and other such factors to manufacture butterfly valves for specific applications. These valves have three main functions:
- Flow Regulation: While butterfly valves are not the best choice for flow regulation, they can still be used for this purpose. By connecting the automatic valve actuator, the flow of the medium can be adjusted through the butterfly valve.
- Flow Isolation: Butterfly valves are an excellent choice for flow isolation because of their fast closing properties. These valves are compact, lightweight, and easy to operate. These valves also enhance pressure recovery and limit pressure drop.
- Stop/Resume Flow: Butterfly valves are best suited for stopping and resuming media flow in piping systems. Their quick shut-off characteristics allow them to stop or resume flow in pipelines.
- Prevention of Backflow: Under certain circumstances, butterfly valves can be used to prevent backflow. These valves are primarily used in such situations in wastewater treatment facilities.
Applications may include:
- Wastewater treatment
- Oil and gas industry
- Chemical industry
- Pipeline transportation
- Marine industry, etc.
Butterfly valves are among the most commonly used industrial valves in many industries including wastewater treatment plants. If you are looking for a qualified valve actuator manufacturer in China, then UG Controls is the right solution for you. UG Controls is a custom valve actuators and accessories manufacturer. Its main business is the import and export of various automation equipment and technologies. UG Controls is a proprietary business solution integrating chemical engineering, water, oil and gas, power plants, manufacturing, food and beverage and more. We also have very distinguished engineers who possess broad and in-depth knowledge in their fields to provide ideal solutions to get the most out of our products. If you want to buy actuators or actuator accessories, please contact us.