What Is the Difference Between a Floating and a Trunnion Ball Valve?

Direct Answer

A floating ball valve suspends the ball between two seat rings without mechanical support — line pressure pushes the ball against the downstream seat to achieve shutoff, making it suitable for small-to-medium bore, moderate-pressure service. A trunnion-mounted ball valve anchors the ball through upper and lower trunnion shafts, isolating seat load from line pressure — enabling reliable low-torque operation in large-bore, high-pressure applications within the industrial valve selection framework.