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Tri Lok

Triple Offset Butterfly Valve


Size Range

NPS 3 to 48 / DN 80 to 1200

Temperature Range

-320°F to 842°F (-196°C to 450°C)

Maximum Allowable Operating Pressure

ASME Class 150, 300, 600, 900
EN 1092 PN 10, 16, 25, 40, 63, 100, 150

Shutoff Rating

Zero Leakage

Body Style

Lug, Wafer, Double Flanged, Gate, Buttweld

Body Materials

Carbon Steel, Stainless Steel

Stem Materials

17-4PH, 410 Stainless Steel, XM-19 (Nitronic 50)

Seat Materials

316 Stainless Steel Hardened

Disc Materials

Carbon Steel, Stainless Steel

Fugitive Emissions Standard

ISO 15848-1, API 641, TA Luft


Triple Offset Butterfly Valve compared to gate, globe or ball valves of the same size and pressure class, Tri Lok provides space and weight savings while minimizing installation and maintenance costs.

Tri Lok is a premier isolation valve, well suited for operation in light vacuum to high-pressure applications. The standard, non-rubbing, metal-to-metal sealing system is inherently fire-safe. Applications requiring absolute zero leakage are ideally suited for triple offset technology.

Materials of Construction

Valve bodies and discs are available in WCB Carbon Steel and CF8M Stainless Steel as standard. Low-temperature Carbon Steel, Duplex Stainless Steel, Monel, Hastelloy® and NiAB are also available. The discs primary function is to “carry” the seal ring. As such, the disc material is commonly the same material as the body to allow full pressure/temperature rating and maintain uniform thermal expansion at elevated temperature. Standard stem materials are 17-4PH, 410 Stainless Steel and XM-19 (Nitronic®). Seat, seal ring and remaining trim are selected to meet the required mechanical properties while providing sufficient corrosion resistance. While the previously mentioned materials are defined as standard, custom engineered configurations are also available.