A trunnion mounted ball valve is a type of ball valve in which the ball is fixed in position by mechanical supports called trunnions. These trunnions absorb pipeline pressure, preventing the ball from moving under load.
Instead of the ball floating against the seat, the valve seats move toward the ball, creating a tight seal even under high pressure. This design makes trunnion mounted ball valves ideal for oil & gas pipelines, LNG systems, and large-diameter applications.
Key components include:
This structure reduces friction, improves sealing reliability, and extends service life.
This pressure-assisted sealing principle ensures consistent performance under both low and high pressure conditions.
Because the ball is fixed, friction between the ball and seats is significantly reduced, making operation easier and safer.
The seat design ensures tight shutoff even in high-pressure or fluctuating conditions.
Reduced wear on internal components leads to fewer maintenance requirements and longer valve lifespan.
Trunnion mounted ball valves are commonly used for DN200 (8”) and above, where floating ball valves become less practical.
Body materials:
Seat materials:
Ball materials:
Trunnion mounted ball valves are widely used in:
They are especially suitable for critical isolation service in long-distance pipelines.
| Feature | Trunnion Mounted Ball Valve | Floating Ball Valve |
|---|---|---|
| Ball design | Fixed with trunnions | Floating |
| Operating torque | Low | Higher |
| Pressure rating | High | Medium |
| Valve size | Medium to large | Small to medium |
| Seat wear | Minimal | Higher |
| Typical applications | Pipelines, oil & gas | General industrial use |
Trunnion mounted ball valves can be operated by:
Low torque requirements make them ideal for automation and remote pipeline control systems.
Most trunnion mounted ball valves are designed and tested according to:
A Trunnion Mounted Ball Valve is a reliable and efficient solution for high-pressure and large-diameter pipeline systems. Its fixed ball design, low operating torque, excellent sealing performance, and long service life make it the preferred choice for critical industrial applications—especially in the oil and gas industry.
For projects where safety, durability, and performance are essential, trunnion mounted ball valves offer long-term value and operational confidence.
