Double Offset Butterfly Valves
Double Offset Butterfly Valves

Kent Double Offset Butterfly Valve is designed to offer rugged reliability and extremely easy maintenance in the field. These valves are bi-directional with zero leak features. Resilient seat design can also achieve low torque, which is easy for operation. Kent High Performance Valves deliver the highest quality and highest value available for meeting today’s demanding requirements of zero leakage. An eccentric butterfly valve means that the stem does not pass through the centerline of the disc, but instead behind it (opposite of flow direction). When the stem is located right behind the centerline of the disc, the valve is called single-offset. This design was developed to reduce the disc contact with the seal before full closure of the valve, with the aim of improving the service life of the valve. Today, single-offset valves have given way to double-offset and triple-offset butterfly valves. In a double-offset or doubly eccentric butterfly valve, the stem is located behind the disc with an additional offset to one side. This double eccentricity of the stem enables the rotating disc to rub over the seat for only about one to three degrees.
Product Standards
Product Details
Special Features
Specifications | Details |
Design Standard | API 609 Category-B, MSS SP-67, EN 593 (BS 5155) |
Pressure/Temperature Chart | ASME B16.34 |
Face to face Dimension | API 609 Table-3B & 3C, MSS SP-67, ASME B16.10 |
Testing Standard | API 598 /MSS SP 61 / BS EN 12266-1 |
Wafer Type | API 609 |
Semi Lug Type | API 609 |
Lug Type | API 609 |
Flange Details | ASME B16.5 UP TO 24″
DIN / BS / IS / JIS |
Size Range | 2″ – 24″ (DN50 – DN600) |
ASME Class | Class 150, PN2.5 to PN 25 |
Materials | Cast Iron, SG Iron, WCB / LCB / LCC / CF8M / CF8 /CF3M / 4A / 6A / Inconel |
Trims | F6a / F316 / F304 / F316L / F51 /F55 / Inconel / 17.4 PH |
Elastomer Seat | Nitrile, EPDM, Viton, Hypalon, Silicon, PTFE, RPTFE |
Ends | Wafer Type, Semi Lug Type, Lug Type, Flange Ends |
Operation | Manual, Pneumatic, Electric |
- Double Offset Butterfly Valve design complies to API 609 Category-B, MSS SP-67, EN 593 (BS 5155).
- Self-energising Disc Seal – Bi-directional bubble-tight sealing.
- With spherical disc, the geometry and construction of the seat results in smooth contact between the seat and the disc. This also results in reduced valve torque.
- Bubble tight shut off over extended period of service.
- One-piece blowout-proof Shaft.
- Integral actuator mounting platform.
- Blowout-proof stem design.
- Stellite hard face on the disc sealing face can be provided upon request.
- Low emission packing set available for special service.
- Live loading can be provided which maintain constant pressure on the gland.
- Actuator-mounting flange conforms to ISO 5211.
- Wafer Type, Semi Lug Type, Lug Type, Flanged ends.