What Is a Triple Offset Butterfly Valve? Structure, Advantages & Applications

What Is a Triple Offset Butterfly Valve?

A Triple Offset Butterfly Valve (TOV) is a high-performance butterfly valve specially designed for high temperature, high pressure, steam, oil & gas, chemical processing, and severe service applications.

Unlike concentric or double offset butterfly valves, the triple offset design uses three geometric offsets that eliminate seat friction during operation, extend service life, and provide bubble-tight shutoff performance.

It is an ideal replacement for gate valves and globe valves in many modern industrial systems.

---

Triple Offset Geometry

1st Offset

The valve stem is positioned behind the seat axis, allowing full sealing contact around the entire seat.

2nd Offset

The shaft centerline is offset from the centerline of the pipe and valve body, allowing interference-free opening and closing.

3rd Offset

The seat cone axis is offset from the shaft centerline, eliminating friction during operation and creating uniform compressive sealing around the full seat circumference.

---

Advantages of Triple Offset Design

✔ Friction-free opening and closing
✔ Long seat life
✔ Low operating torque
✔ Bubble-tight shutoff
✔ Suitable for high temperature service
✔ Suitable for high pressure service
✔ Fire-safe design available
✔ Excellent for frequent cycling
✔ Low maintenance cost

---

Working Principle

The valve operates by rotating the disc 90 degrees.

• During opening, the disc moves away from the seat immediately, reducing wear.
• During closing, torque forces the disc evenly against the seat.
• Line pressure assists sealing performance.

---

Design Standards

Design

• API 609 Category B
• ASME B16.34

Face to Face

• API 609 Category B
• Wafer Type
• Lugged Type
• Double Flange Short / Long Pattern

Flange Standards

• ASME B16.5 / B16.47
• BS 4504
• EN 1092-1
• JIS B2220
• Others on request

---

Pressure Ratings

• Class 150
• Class 300
• Class 600
• Class 900
• Class 1500

---

Available Sizes

• 3” to 144”
• DN80 to DN3600

---

End Connections

 

✔ Wafer Type
✔ Lugged Type
✔ Double Flanged Type

---

Optional Features

• Anti-static Device
• Cryogenic Design
• Extended Stem
• Gear Operator
• Pneumatic Actuator
• Electric Actuator
• Special Design on Request

---

Testing Standards

• API 598
• ASME B16.104 / FCI 70-2
• ISO 5208

---

Available Materials

Carbon Steel

• A105
• A216 WCB
• WCC
• WC6
• WC9

Low Temperature Carbon Steel

• A350 LF2
• A352 LCB
• LCC

Austenitic Stainless Steel

• A182 F304
• A182 F316
• A351 CF8
• CF8M
• CF3
• CF3M

Duplex / Super Duplex

• A182 F51
• F53
• F55
• A995 4A / 5A / 6A

Special Alloys

• Inconel 625 (UNS N06625)
• 254SMO (UNS S31254)
• Monel K400 / K500

---

Applications of Triple Offset Butterfly Valve

 

✔ Power Plants
✔ High Pressure Steam Lines
✔ Cement Plants
✔ Offshore & Onshore Oil & Gas
✔ Refineries
✔ Chemical Plants
✔ LNG / LPG Terminals
✔ Pulp & Paper Plants
✔ Large Industrial Water Systems

---

Comparison with Standard Butterfly Valve

---

Why Choose PM-E?

PM-E specializes in supplying high quality Triple Offset Butterfly Valves for industrial applications.

Our Commitments:

✔ Correct model selection
✔ Correct material supply
✔ Full CO/CQ documents
✔ Competitive pricing
✔ Fast delivery
✔ Technical support

---

Contact Us

PHUC MINH ENGINEERING CO., LTD
🌐 Website: kythuatphucminh.com
🌐 Website: pm-e.vn
📧 Email: info@pm-e.vn
📞 Hotline: +84 907 450 506
📞 Hotline: +84 902 720 814

---

Conclusion

A Triple Offset Butterfly Valve is the best solution for systems requiring tight shutoff, high temperature resistance, high pressure capability, and long service life. It is a preferred valve choice for modern industrial plants. Contact PM-E today for technical support and quotation.