Flanged Double Eccentric High-Performance Butterfly Valve

Product Advantages

● Excellent Sealing Performance: Reliable shut-off under Class150 and Class300 pressures.
● Extended Service Life: Reduced disc-to-seat friction minimizes wear.
● High Structural Stability: Flanged design improves installation reliability.
● Energy Efficient Operation: Low torque reduces actuator energy consumption.
● Wide Application Flexibility: Suitable for liquids, gases, and light chemical services.

Size Range

● NPS 2″ – 24″ (DN50 – DN600)

Pressure Rating

● Class 150 / Class 300

Standards

● Design Standard: API 609 / EN 593
● Test Standard: API 598 / EN 12266
● Flange Standard: ASME B16.5

Industry Applications

● Oil & gas pipelines
● Chemical and petrochemical plants
● Power generation systems
● Industrial water and wastewater treatment
● HVAC and district energy systems
● Marine and offshore facilities

FAQs

1. When does a flanged connection make more sense than a wafer-style butterfly valve?
A flanged valve bolts independently to each pipe flange, so it can be removed from the line without disturbing the rest of the piping — a wafer valve, clamped between two flanges, generally can’t be pulled without loosening the adjacent pipework first. Flanged is also the safer choice at the dead end of a line, since a wafer valve isn’t rated to hold pressure with only one side bolted.

2. Does the flanged design change the pressure rating compared to a wafer version?
Not inherently — pressure rating is driven by the disc/seat design and body material, so a flanged and wafer version of the same valve platform typically share the same Class 150/300 rating. The flanged body does add rigidity that some specs specifically require for larger diameters or higher-vibration service.

3. What flange standard does this valve bolt to, and does it matter which one I specify?
It’s built to ASME B16.5 flange dimensions — if your piping uses a different standard (e.g., EN 1092), the bolt circle and hole spacing won’t line up, so confirming flange standard compatibility before ordering avoids a costly mismatch at installation.

4. Can a flanged butterfly valve be used as an end-of-line shutoff, or does it need pipe on both sides?
Yes — unlike a wafer valve, a flanged valve is self-supporting with pipe on only one side, since both flange faces are independently bolted rather than relying on clamping pressure from both directions.

5. How does a double eccentric butterfly valve reduce seat wear?

The disc moves away from the seat during the initial opening movement, reducing rubbing between the sealing surfaces. This helps minimize friction and wear compared with a concentric design.