<p>A ball valve including coupled outer casing elements adapted to enclose a rotationally movable valve body having a flow passageway therethrough is provided. An annular sealing member is disposed adjacent each of the opposite ends of the flow passageway between the movable valve body and the outer casing elements. An annular resilient member having a U-shaped cross-section and opposed walls comprising a plurality of resilient segments is loaded in each of the sealing members to spring-load each of them into sealing engagement with the movable valve body and outer casing elements. The movable valve body is supported by a cone spring which is in point contact with the outer casing elements and line contact with the movable valve body.</p>