What is A Butterfly Valve: the Complete Guide

  • 2024.12.30
  • Knowledge

In pipe systems, butterfly valves are widely used due to their high cost-effectiveness and compact installation space. These valves are found in various industrial fields. This article will provide a detailed introduction to butterfly valves, covering their working principles, types, advantages, and applications.

For more information on choosing the right sanitary fittings and valves for your industry, check out How to Choose the Right Sanitary Fittings & Valves for Your Industry.

Construction of Butterfly Valve

A butterfly valve is a quarter-turn valve that controls and regulates the flow of fluid in a pipe system. The main structures of a butterfly valve include an actuator, a valve stem, a valve disc, a valve seat, a valve body sealing, and a valve body.

Actuator

It refers to the driving device that drives the butterfly valve, which usually has four types: manual, electric, pneumatic and hydraulic. Manual is the simplest driving force and the cheapest. The other three driving forces are very suitable for use with automation systems, and the cost is relatively high.

Valve Stem

The valve stem is the component that connects the actuator and the valve disc. By operating the valve stem, the valve disc connected to it can be controlled to rotate, achieving the effect of controlling the opening and closing of the butterfly valve. Usually, there are certain requirements for the strength and durability of the valve stem, otherwise it is easy to cause mechanical wear and affect the operation of the butterfly valve.

Valve Disc

The valve disc is an important part inside the butterfly valve, connected to the valve stem. The valve disc rotates to control the opening and closing of the butterfly valve, allowing or preventing the flow of fluid. Depending on the different fluids and media, the material of the valve disc is also different. Common materials include stainless steel, rubber, etc. 

Valve Seat

The valve seat is usually in close contact with the valve disc, providing a tight sealing effect. When the butterfly valve is closed, it fits tightly with the valve disc to ensure a good sealing effect. There are different material options depending on the type of media.

Valve Body Sealing

This component is usually located at the connection between the valve body and the pipe to ensure the sealing of the pipe and the valve to prevent leakage. To ensure the sealing effect, the durability of valve body sealing must be excellent.

Working Principle

The valve disc inside the butterfly valve is rotated 90 degrees by operating the valve stem. At this time, the valve disc is parallel to the flow direction of the fluid in the pipe system, and the butterfly valve is in a fully open state, allowing the fluid to pass smoothly. 

When the valve disc is rotated 90 degrees again so that the valve disc is perpendicular to the flow direction of the fluid, the valve seat and the valve disc form a tight seal, the butterfly valve is in a completely closed state, and the fluid cannot pass through.

Types of Butterfly Valves

Butterfly valves can be classified based on their connection method and operation mode.

Based on the Connection Method

Wafer-Type Butterfly Valve

Installed between two pipes using bolts, the wafer-type valve is easy to install. It also provides bidirectional pressure sealing, making it suitable for medium- and low-pressure systems.

Lug-Type Butterfly Valve

Featuring lugs on the valve body, the lug-type valve is also connected to the pipe with bolts. It allows for maintenance at one end without interrupting fluid flow, offering great flexibility.

Flange-Type Butterfly Valve

This valve has a flange on its body, enabling it to be connected via flange bolts. It is ideal for large-diameter pipes and high-pressure systems.

Based on the Operation Mode

Manual Butterfly Valve

The simplest and most cost-effective option, this valve is operated by a handle or lever and is suitable for systems without automation needs.

Automatic Butterfly Valve

These valves can be electric, pneumatic, or hydraulic, offering various automation and control options.

  • Electric Butterfly Valve: Uses electricity to open/close the valve, suitable for automation and remote-control systems.
  • Pneumatic Butterfly Valve: Driven by compressed air, this valve has a fast response speed and is used in hazardous environments like the petroleum and chemical industries.
  • Hydraulic Butterfly Valve: Operated by hydraulic pressure, it is ideal for high-demand automation systems.

Advantages of Butterfly Valve

Butterfly valves offer several benefits, making them a popular choice in many pipe systems:

Compact Structure and Small Installation Space

Butterfly valves are lightweight and compact, taking up less space and reducing the overall weight on the pipe system.

Quick Opening and Closing

These valves can open and close quickly with just a 90-degree rotation of the valve stem.

Low Cost

Butterfly valves are affordable, making them a cost-effective solution for many systems.

Easy to Maintain

With their simple design, butterfly valves are easy to maintain, which reduces overall maintenance costs.

Applications of Butterfly Valve

Butterfly valves are used across various industries, including petroleum, water supply, chemicals, and pharmaceuticals. They come in different materials and sealing types to suit various pressures and environments. For example, stainless steel butterfly valves are ideal for corrosive environments due to their excellent resistance and durability.

If you're interested in learning more about the different types of stainless steel valves, you can read Several Types of Stainless Steel Valves You Are Interested In.

Conclusion

Butterfly valves play a critical role in industrial pipe systems. They are especially useful in medium- and low-pressure systems, as well as in large-diameter pipes. The performance of butterfly valves makes them indispensable in many applications.

If you would like to learn more about butterfly valves or want to make a purchase, please visit our Contact Page for more information.

Precision Camlock
Fittings Manufacturer

Get a Quote Today
Read more post

Related Reading

Select Your Language