Home > Products > Water Treatment Valves > Lug Type Butterfly Valve

Lug Type Butterfly Valve

The valve body of a lugged type soft sealed concentric butterfly valve is usually cast from ductile iron or various metal steel. The valve has threaded lugs on the flange for bolted connections. They are suitable for end of line services, although it is recommended to use blind flanges to increase safety. These valves are designed to adapt to pneumatic and electric drives, and the selection of valve disc and seat materials depends on specific application requirements and flow medium characteristics. Butterfly valves are a commonly used fluid control device, and the lug design has stronger pressure bearing capacity and more stable performance than the wafer design.

Structural Features

Lug type butterfly valve is characterized by their unique design, which includes threaded inserts (or “lugs”) around the valve body. These lugs allow the valve to be bolted directly into a pipe system, providing a secure and stable connection. One of the primary benefits of this design is its ability to be used in end-of-line service, meaning the valve can be installed at the end of a piping system without the need for additional support.

  • Lugged butterfly valves have a body with two lugs cast or welded onto it. These lugs allow the valve to be bolted to a flat surface like a flange. Wafer butterfly valves have a body with a groove machined into it. This groove allows the valve to be squeezed between two flat surfaces, providing a seal.
  • Lugged butterfly valves are more expensive than wafer ones but provide a stronger connection. Wafer butterfly valves are less costly but can be more challenging to install.
  • Lugged butterfly valves have a round disc with lugs that attach the disc to the valve’s body. Wafer butterfly valves have a disc attached to the valve’s body with screws or bolts. Both types of butterfly valves are used to control the flow of liquids and gases.
  • Lugged butterfly valves are easier to maintain than wafer butterfly valves because the lugs allow the disc to be removed without removing the entire valve. Wafer butterfly valves are less likely to leak than lugged butterfly valves because the sealing surfaces are more accurate.
  • Lugged butterfly valves are typically used in high-pressure applications, while wafer butterfly valves are usually used in low-pressure applications.
  • The lugs are strategically placed around the valve body, allowing for easy alignment and secure bolting.
  • The valve’s body is designed to minimize space usage while maintaining high performance.
  • Lug type butterfly valve can provide sealing in both directions, making them versatile for various flow control applications.

Applications

  • End-of-Line Service: Ideal for systems where the pipe ends, ensuring that the valve can be securely closed without additional support.
  • Isolation Applications: Frequently used in isolation applications where sections of the piping system need to be shut off for maintenance.
  • Pipeline Maintenance: The design allows one side of the pipeline to be disconnected while the other remains operational, which is useful during maintenance or repairs.

Dimension

SIZE DN Φ D L N – NUC C Φ G
in mm A-series B-series mm A-series B-series
2 50 120.7 43 4 – 5/8″ <11> F05 9 X 9
2 1/2 65 139.7 46 4 – 5/8″ <11> F05 9 X 9
3 80 152.4 46 4 – 5/8″ <11> F05 9 X 9
4 100 190.5 52 8 – 5/8″ <11> F07 11 X 11
5 125 215.9 56 8 – 3/4″ <10> F07 14 X 14
6 150 241.3 56 8 – 3/4″ <10> F07 14 X 14
8 200 298.5 60 8 – 3/4″ <10> F10 17 X 17
10 250 362 68 12 – 7/8″ <9> F10 22 X 22
12 300 431.8 78 12 – 7/8″ <9> F10 22 X 22
14 350 476.3 78 12 – 1″ <8> F10 22 X 22
16 400 539.8 102 16 – 1″ <8> F14
18 450 577.9 114 16 – 1 1/8″ F14
20 500 635 127 20 – 1 1/8″ F14
24 600 749.3 154 20 – 1 1/4″ F16
28 700 863.6 795.3 165 28 – 1 1/4″ 40 – 3/4″ <10> F25
32 800 977.9 900.1 190 28 –  1 1/2″ 48 – 3/4″ <10> F25
36 900 1085.8 1009.6 203 32 – 1 1/2″ 44 – 7/8″ <9> F25
40 1000 1200.2 1120.8 216 36 –  1 1/2″ 44 – 1″ <8> F25
48 1200 1422.4 1335.1 254 44 –  1 1/4″ 44 – 1 1/8″ F30

MORE DETAILS OR REQUIREMENTS NEED TO BE CONFIRMED PLEASE DOWNLOAD THE CATALOG OR CONTACT US

Conclusion

Lug type butterfly valves are a reliable choice for industrial applications requiring a durable, easily maintainable valve solution. Their unique design ensures that they can handle high pressure and provide a tight seal, making them suitable for a wide range of uses, from water treatment plants to chemical processing facilities.