Compared to gate valves, triple offset butterfly valves deliver exceptional zero-leakage performance in a wide range of temperatures and pressures. They are ideal for handling harsh media and can be used with a variety of applications, including power generation, petroleum, chemical processing, water treatment, and more. Triple-offset butterfly valves feature a unique sealing design that minimizes friction between the disc and seat, providing low-running torque and long life in even cyclic operations.Go here:https://www.shiphamvalves.com/solution-category/triple-offset-butterfly-valves/
The first offset in a triple-offset butterfly valve relates to the location of the shaft center line and the center line of the disc/seat sealing surfaces. This eliminates rubbing between the two surfaces and preserves their seal integrity over the entire operating cycle. The third and final offset refers to the geometry design of the seal components, which produces a right-angle cone shape that ensures frictionless stroking throughout the valve’s operation. The 90-degree angle also acts as a mechanical travel stop, prohibiting any overtravel of the disc seat.
The Engineering Marvel: Exploring the Design Principles of Triple Offset Butterfly Valves
A metal-to-metal seal allows triple offset valves to operate in abrasive and corrosive media, with no cavities between the seat and disc that can accumulate debris. The valve body seat is typically made from Stellite grade 21 or Duplex stainless steel, which offers high abrasion resistance and withstands temperature fluctuations.
Triple-offset butterfly valves also feature independent thrust rings on both the upper and lower sides of the disc to prevent any deformation or displacement of the seat surface. This ensures consistent and accurate seating of the disc against the seat surface, even under heavy cyclic loads.