Industrial butterfly valves are a type of quarter-turn valve used to control the flow of liquids or gases through a pipe or duct. They are called “butterfly” valves due to the wing-like disc that rotates on a shaft to regulate the flow. Here’s an overview of industrial butterfly valves:

1. Design: Industrial butterfly valves consist of a circular body with a disc mounted on a shaft in the center. The disc can be rotated a quarter turn (90 degrees) to either allow full flow or completely shut off the flow. When fully open, the disc is parallel to the flow direction, minimizing pressure drop.

2. Types:

   • Concentric: In concentric butterfly valves, the center of the shaft is aligned with the center of the pipe, resulting in a uniform seal around the circumference of the disc. They are commonly used for general applications with non-corrosive fluids.
   • Eccentric: Eccentric butterfly valves have the shaft offset from the center of the pipe, allowing the disc to fully contact the seat, even when partially open. This design is suitable for high-performance applications and handling abrasive or corrosive fluids.

3. Materials: Industrial butterfly valves are available in various materials to suit different operating conditions and fluid media. Common materials include carbon steel, stainless steel, cast iron, and various alloys. The choice of material depends on factors such as fluid compatibility, temperature, pressure, and environmental conditions.

4. Actuation: Butterfly valves can be operated manually or automatically (actuated) using pneumatic, electric, or hydraulic actuators. Actuators allow for remote control and automation of the valve operation, which is essential in industrial processes where precise flow control is required.

5. Applications:

   • Water Treatment: Butterfly valves are commonly used in water treatment plants for regulating the flow of water, wastewater, and chemicals.
   • HVAC Systems: They are used in heating, ventilation, and air conditioning (HVAC) systems for controlling the flow of air, water, or refrigerants.
   • Chemical Processing: Butterfly valves are utilized in chemical processing industries for handling various corrosive and abrasive fluids.
   • Power Generation: They find applications in power plants for controlling the flow of steam, cooling water, and other fluids in power generation processes.

6. Advantages:

   • Quick Operation: Butterfly valves can be opened or closed rapidly with a quarter-turn operation.
   • Low Pressure Drop: When fully open, butterfly valves offer minimal obstruction to flow, resulting in low pressure drop across the valve.
   • Compact Design: They have a relatively compact and lightweight design compared to other types of valves, making them suitable for space-constrained installations.
   • Cost-Effective: Butterfly valves are often more cost-effective than other valve types, especially for larger pipe sizes.

7. Disadvantages:

   • Limited Control: Butterfly valves may not provide the same level of flow control precision as some other valve types, such as globe valves.
   • Limited Suitability for High-Pressure Applications: While suitable for many industrial applications, butterfly valves may not be ideal for extremely high-pressure systems.

Overall, industrial butterfly valves offer a versatile and cost-effective solution for flow control in a wide range of industrial applications.