Abstract: A valve seat (30) for a ball valve (1) includes an annular body having a central aperture (36) defining a longitudinal flow channel, a first seating surface (38) for engaging and sealing against a corresponding portion of a fluid conduit and a longitudinally opposed second seating (40) surface for engagement with a valve ball. The first seating surface comprises a convex surface profile. The convex profile of the seat (30) allows the stresses incurred during loading from the valve ball (1) to be widely and evenly distributed throughout the structure of the seat (30).

Abstract: A valve including a valve body having a bore and a spindle received in the bore, the spindle being actuatable to open and close the valve. A compression gland seal is provided about the spindle for compression between the spindle and the bore. A first seal ring is provided about the spindle at a position spaced along the spindle from the gland seal, and provides a seal between the spindle and the bore of the valve body. A second seal ring is provided about the spindle at a position spaced along the spindle from the gland seal and the first seal ring, and provides a further seal between the spindle and the bore of the valve body.

Abstract: A valve including a valve body having a bore and a spindle received in the bore, the spindle being actuatable to open and close the valve. A compression gland seal is provided about the spindle for compression between the spindle and the bore. A first seal ring is provided about the spindle at a position spaced along the spindle from the gland seal, and provides a seal between the spindle and the bore of the valve body. A second seal ring is provided about the spindle at a position spaced along the spindle from the gland seal and the first seal ring, and provides a further seal between the spindle and the bore of the valve body.