• INDUSTRY OUTLOOK •
When TOVs began achieving similar shutoff classes and fire-safe ratings, many assumed they were functionally equivalent— just lighter. Triple offset valves depend on directional, geometry-sensitive cam sealing. Assuming they behave like ball valves leads to costly surprises.
The Source of Confusion Some end users still treat triple offset valves like ball valves since:
• They expect symmetry in sealing.
• They assume metal-seated equals“ rugged.”
• They do not understand the critical role of flow direction in the sealing mechanism.
Additionally, procurement practices often emphasize " standardization " and low cost over application-specific design, which further compounds the issue.
Triple offset valves depend on directional, geometrysensitive cam sealing … assuming they behave like ball valves leads to costly surprises.
This can be rectified by educating teams on the flow-directional nature of TOV sealing as well as by specifying reverse sealing only if it is truly needed( a huge percentage of applications are for unidirectional flow yet bi-directional is still insisted upon).
It is also recommended to request evidence of engineered capabilities, and to not use TOVs like ball valves. Think of them more like precision isolation or control valves with complex geometry and mechanical dynamics.
Conclusion Triple offset valves are exceptional when used as intended. Unless reverse sealing is part of the original design— including shaft sizing and offset geometry— you’ re not just asking a valve to do more; you’ re asking it to do something it was never designed for.
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• ABOUT THE EXPERT •
Bernard Horsfield’ s experience in valves and controls spans more than 35 years, during which he has held numerous engineering and sales positions. He now leads Rodefish Ltd., which specializes primarily in triple offset valves, while also bringing extensive expertise in ball, butterfly, and control valves.
Valve World Americas | October 2025 | www. valve-world-americas. com 13