Cast iron butterfly valve

A cast iron butterfly valve is a type of flow control valve that:

1. Regulates fluid flow by rotating a disc (butterfly) 90 degrees.
2. Allows for on/off or throttling control.
3. Consists of:
    - Body: Cast iron housing containing the valve mechanism.
    - Disc (Butterfly): Rotating element that controls flow.
    - Stem: Connects the disc to the actuator (handle or gearbox).
    - Seat: Surfaces that seal when the valve is closed.
    - Packing: Seals around the stem to prevent leaks.
4. Operates in various ways:
    - Manual (handle or wheel)
    - Actuated (electric, pneumatic, or hydraulic)

Cast iron butterfly valves are suitable for:

1. Water supply systems
2. Wastewater treatment
3. Chemical processing
4. HVAC systems
5. Industrial processes (oil, gas, steam)

Advantages:

1. Robust and durable
2. High-temperature resistance
3. Corrosion-resistant coatings available
4. Easy to install and maintain
5. Cost-effective

Disadvantages:

1. Limited to moderate pressure and temperature ranges
2. May require additional maintenance for packing and seals