Abstract: A ball valve comprising a housing having a cylindrical bore extending inwardly from the exterior and defining a valve chamber with inlet and outlet passages connected from the exterior of the housing to the chamber. A ball valve member is positioned axially in the chamber and has a cylindrical operating stem extending axially of the bore into a position exterior of the housing. Positioned within the chamber is a mass of resilient packing material which surrounds the ball and substantially fills the chamber. Adjustable means are provided for applying a compressive load to the packing to cause it to sealingly engage the inner walls of the chamber and the exterior of the ball member. The adjustable means include a rigid circular gland member closely received in the bore and extending transversely thereof in engagement with the packing. A circular opening in the gland member closely surrounds the operating stem and disk spring means are positioned on the gland member on the side opposite the packing.