A butterfly valve consists of several key parts that work together to control the flow of fluid. Here are the main parts:
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Body: This is the main housing of the valve, usually cylindrical or spherical in shape, where the other components are mounted.
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Disc (or Butterfly): The disc is a flat or slightly curved plate that is mounted in the center of the valve body. It rotates around an axis perpendicular to the direction of flow to control the flow of fluid. When the disc is parallel to the flow, it allows full flow, and when it's perpendicular, it blocks flow.
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Stem: The stem is a shaft connected to the disc that extends outside the valve body. It's used to rotate the disc to open or close the valve.
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Seat: The seat is the part of the valve body against which the disc seals when the valve is closed. It ensures tight shut-off and prevents leakage.
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Actuator: In some cases, a butterfly valve may be equipped with an actuator, which is a device that provides the power to operate the valve. Actuators can be manual, electric, pneumatic, or hydraulic, depending on the application and required level of automation.
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Shaft Bearings: These are bearings that support the shaft and allow it to rotate smoothly when operating the valve.
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Body Liner: In some butterfly valves, especially those used in corrosive environments, a liner made of materials like rubber or PTFE (polytetrafluoroethylene) is added to the valve body to protect it from the fluid and enhance sealing.
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Handle or Lever (for manual valves): Manual butterfly valves typically have a handle or lever attached to the stem to manually rotate the disc and control the flow.
These are the basic components of a butterfly valve. Depending on the design and specific application, there might be additional features or variations in these parts.
