Abstract: A ball valve comprises a cylindrical casing having an axial bore therethrough for passage of fluids. The ball is mounted between annular upper and lower seats, the latter being compressible and supported by an annular shoulder within the casing. The ball has diametrically opposed slots that receive a pin and a wrench plug, respectively, which are rotatably mounted within diametrically opposed longitudinal apertures in the casing. The ball has a large central bore therethrough whose axis is perpendicular to the ball's rotational axis, so that the fluid path may be opened and closed by rotating the ball. Prior to loading the valve, the ball is in its closed position in which the slots are parallel to the axis of the casing, thereby permitting the ball to float axially between the seats. In order to load the valve under compression, the wrench plug is manually rotated with a wrench until the ball is turned to its open position. This rotation cams the ball downward against the lower seat, compressing the seat.