What is a butterfly valve?
Butterfly valve is named butterfly valve because its shape resembles a butterfly. The actuator rotates the valve plate 0-90 degrees to open and close the valve, or to briefly adjust the flow rate.
What is a ball valve?
Ball valves are also used in pipelines to control valves that regulate fluid flow. They typically use a sphere with a hole to control the flow of fluid, which can pass through or be blocked as the sphere rotates.
As fluid control components, butterfly valves and ball valves can both be used to connect and cut off the medium in the pipeline. What are the differences, advantages and disadvantages? Below we analyze it from the structure, scope of application, and sealing requirements.
1. Structure and principle
- The opening and closing part of the butterfly valve, the valve plate, as the name implies, is a plate-shaped piece with a certain thickness, while the opening and closing part of the ball valve is a sphere.
- Butterfly valves are simpler and have a compact structure, so they are lighter in weight; while ball valves have a longer body and require a larger space when opening and closing. They tend to be larger and heavier.
- When the butterfly valve is fully open, the valve plate rotates parallel to the direction of flow, allowing unrestricted flow. When the butterfly valve is closed, the valve plate is perpendicular to the direction of medium flow, thus completely blocking the flow.
- When a full-bore ball valve is fully open, the holes align with the pipe, allowing fluid to pass through. And when closed, the ball rotates 90 degrees, completely blocking flow. Full bore ball valve minimizes pressure drop.
2. Scope of application
- Butterfly valves can only be used for two-way flow; ball valves can also be used as three-way diverters in addition to two-way flow.
- Butterfly valves are suitable for on/off control of low-pressure pipeline media; ball valves can be used for precise flow control in higher temperature and pressure situations.
- Butterfly valves are widely used in sewage treatment, food processing, HVAC systems, air conditioning systems and other fields; ball valves are mainly used in petroleum, natural gas, chemical industry, metallurgy, electric power and other industrial fields.
3. Sealing
- Soft-sealing butterfly valves rely on elastic valve seats such as rubber or PTFE to form a seal by squeezing around the valve plate. There is a certain chance that this seal will degrade over time, potentially causing leaks.
- Ball valves typically feature metal-to-metal or soft seat seals that provide a reliable seal even after long-term use.
In summary, butterfly valves and ball valves each have their own advantages and disadvantages, and which valve to choose depends on the specific application scenarios and needs.
ZFA Valve Company is a factory specializing in the production of various butterfly valves. If you have any questions, please feel free to contact us.