The Double Offset Disc Butterfly Valve (also known as a High-Performance Butterfly Valve) is engineered for applications where standard resilient-seated valves fall short. By utilizing a sophisticated double-eccentric design, the disc is offset from both the center of the shaft and the center of the valve body.
This geometry allows the disc to "lift" off the seat immediately upon opening, drastically reducing friction, minimizing wear, and extending the service life of the seal. It is the premier choice for high-pressure, high-temperature, and high-cycle industrial environments.
Key Features & Benefits:-
- Extended Seat Life: The double offset geometry eliminates seat interference during the majority of the stroke, preventing the "scuffing" or "tearing" common in concentric valves.
- Low Operating Torque: Because the disc breaks contact with the seat early in the opening cycle, significantly less torque is required, allowing for the use of smaller, more cost-effective actuators.
- Bi-Directional Bubble-Tight Seal: Designed to provide 100% leak-proof shut-off in both directions, even under high-pressure fluctuations.
- High-Temperature Capability: Available with specialized Fire-Safe designs or reinforced PTFE/Metal seats to handle extreme temperatures and aggressive media.
- Precision Throttling: Excellent control characteristics make it suitable for both isolation and high-frequency regulating services.
Technical Specifications:-
| Feature |
Specifications |
| Size Range |
2" to 48" (DN50 – DN1200) |
| Pressure Ratings |
ANSI Class 150, 300, 600 |
| Body Materials |
WCB (Cast Steel), LCB, CF8M (316 SS), Monel, Duplex |
| Seat Materials |
RPTFE (Reinforced Teflon), Fire-Safe (PTFE + Metal), Inconel |
| Stem Design |
Anti-Blowout Stem with ISO 5211 Top Flange for Automation |
| Design Standards |
API 609, ASME B16.34, MSS-SP-68 |
Target Industrial Applications:-
The Double Offset Butterfly Valve is the workhorse of heavy industry:
- Oil & Gas: Refining, petrochemical processing, and hydrocarbon transport.
- Power Generation: High-pressure steam, condensate return, and cooling water systems.
- Chemical Processing: Handling volatile organic compounds (VOCs) and corrosive acids.
- Pulp & Paper: Black liquor, steam, and abrasive chemical lines.
- Marine & Shipbuilding: Fuel oil transfer, ballast water, and sea chest isolation.
Why Choose Double Offset over Concentric Valves?
While concentric butterfly valves are excellent for low-pressure water systems, they rely on constant seat compression that leads to premature failure in demanding conditions. The Double Offset Disc Butterfly Valve solves this by mechanically separating the sealing surfaces during operation. This translates to lower maintenance costs, fewer shutdowns, and a significantly higher return on investment (ROI) for your facility.
