Triple Offset Metal-Seated Butterfly Valve
Engineered with a true non-rubbing triple eccentric geometry that generates cam-action disc engagement, delivering 100% bi-directional bubble-tight shutoff (API 598 Rate A) with zero seat friction. Ideal for high-pressure steam, LNG cryogenic services down to -196℃, and hydrocarbon isolation where gate valves are too heavy.
Design Codes & Construction Criteria
Engineered to API 609 Category B dimensional and wall thickness rules, providing significant weight and envelope savings compared to gate and ball valves while delivering bi-directional zero-leakage shut-off.
| Engineering Parameter | Applicable Codes, Standards & Design Criteria |
|---|---|
| Design & Manufacturing Standard | API 609 Category B, ASME B16.34, EN 593, ISO 10631 |
| Face-to-Face Dimensions | API 609 Table 2, ASME B16.10 (short / long pattern), ISO 5752, EN 558-1 Series 13 / 14 |
| Flanged End Connections | ASME B16.5 (NPS ≤ 24"), ASME B16.47 Series A / B (NPS > 24"), EN 1092-1 |
| Triple Eccentric Geometry | 1st Offset: Shaft behind seating plane; 2nd Offset: Shaft off pipe center; 3rd Offset: Inclined cone angle |
| Bi-Directional Shut-Off | Zero bubble leakage in both forward and reverse pressure directions per API 598 Rate A |
| Fire-Safe Certification | API 607 7th Edition, ISO 10497 (inherent metal-to-metal seating architecture) |
| Fugitive Emission Containment | ISO 15848-1 Class AH (< 10 ppm), API 641, TA-Luft compliance |
| Operating Temperature Range | Standard: -29℃ to +425℃; Extended bonnet cryogenic: down to -196℃; High-temp alloy: up to +650℃ |
| Actuation Interface | Standard ISO 5211 mounting pad for quarter-turn scotch yoke, pneumatic, electric, or gear operators |
The Engineering Geometry of Triple Offset Design
How three distinct geometric offsets eliminate seat friction and prevent galling during 90-degree rotary travel.
Offset 1: Shaft Behind Seat
The valve shaft center is positioned behind the plane of the seat sealing surface, creating a continuous uninterrupted 360-degree seal profile around the entire disc circumference.
Offset 2: Shaft Off-Center
The shaft is offset from the pipe and valve centerline. This offset generates a cam-like swinging motion, lifting the disc completely clear of the seat immediately upon opening.
Offset 3: Conical Axis Angle
The cone axis of the seating profile is inclined relative to the pipe axis. This eliminates all sliding friction, ensuring contact occurs only at the final point of closing like a cone in a cup.
Field-Replaceable Seal Ring
Laminated 316SS and graphite composite seal ring is mounted onto the disc with a heavy retaining ring, making it easily inspectable and replaceable without removing the valve body from the pipeline.
Stellite 6 Hard Body Seat
Solid cobalt-base Stellite 6 overlay is plasma welded directly to the body casting, providing a hardness of HRC 38–42 to prevent particulate scoring and wire-drawing erosion under high pressure drops.
Cryogenic Extension Bonnet
For LNG and liquid nitrogen service down to -196℃, a vapor-column extension bonnet isolates the stem gland packing from cryogenic temperatures, preventing packing freeze-up.
Complete Triple Offset Butterfly Valve Models & Technical Capabilities
Browse TSV's complete portfolio of certified triple offset butterfly valve models. Engineered to order with customizable trims, metallurgy, pressure ratings, and factory-fitted actuation for mission-critical installations.
Bi-Directional Zero Leakage Triple-Offset Metal Seated Butterfly Valve
Tri-conical geometry completely eliminates rubbing friction between disc seal ring and body seat, achieving bubble-tight bi-directional shutoff up to Class 600.
Large-Diameter Heavy Transmission Triple Eccentric Butterfly Valve
Heavy-duty double flanged body with splined one-piece blowout proof drive shaft designed for cooling water intake and industrial manifold lines.
High-Temperature & Cryogenic Triple Offset Isolation Butterfly Valve
Equipped with solid Stellite 21 metal-to-metal seating and extended column bonnet for extreme thermal boundaries in LNG and refinery furnace feeds.
Explore All 5 Butterfly Valve Sub-Categories
1:1 aligned with TSV factory catalog. Severe-service metal-seated and resilient-seated quarter-turn isolation valves.
Triple Offset Butterfly Valve
Bi-directional zero-leakage metal-to-metal seating for high-temperature steam and hydrocarbon lines.
Current Series View Page Top ↑Double Flanged Butterfly Valve
Heavy double-flanged body suitable for dead-end service and large diameter cooling water pipelines.
Double Flanged View Double Flanged Butterfly Valve →Wafer Type Butterfly Valve
Compact lightweight body designed for tight installation envelopes between pipeline flanges.
Compact Wafer View Wafer Type Butterfly Valve →Lugged Body Butterfly Valve
Threaded lug holes allowing downstream piping removal while maintaining upstream pressure boundary.
Full Lugged View Lugged Body Butterfly Valve →Resilient Seated Butterfly Valve
EPDM / NBR / PTFE lined body for bubble-tight isolation in water treatment and HVAC systems.
Resilient Lined View Resilient Seated Butterfly Valve →Configure & Request a Quote for Triple Offset Butterfly Valves
Submit your line operating parameters. Our technical engineers will calculate operating torque, check cavitation index, and return full GA drawings within 24 hours.