Abstract: A dampener for a clapper valve wherein a rotor member having radially outwardly extending vanes which subdivide each of two fluid cavities defined in a housing into first and second fluid volumes is characterized by radially extending, first and second passages axially spaced within the rotor which respectively communicate each of the first volumes and the corresponding second volume. The increase in pressure within either of the volumes generated by the motion of the vanes (which move with the clapper) is accommodated by the fluid in one passage venting to the other passage through an axially movable valve. The valve piston presents equal surface areas to each passage, to thereby fluid balance the damper in both the opening and closing directions of the clapper. A bypass channel is provided through which one of the fluid volumes in the first cavity with one of the volumes in the second cavity.

Abstract: A pump is shown with a sealing means for providing static seals along liners slidably receiving the pistons of the pump. The sealing means includes a metal cylindrical ring having a generally wedge-shaped outer edge. In the wedge-shaped outer edge is bonded a resilient sealing material, which sealing material extends outwardly from the metal ring at a small angle. The resilient sealing material also extends beyond one end of the metal ring with an undercut on the innermost edge of the resilient material. After assembly, the metal ring provides a stiff assembly necessary for intermittent operation of the pump in climates having large temperature variations. The resilient sealing material provides sealing along two adjacent surfaces of the liners. Other seals along the liner may be replaced to include combinations of metal for stiffness and resilient material for sealing.

Abstract: A check valve has a clapper pivotally mounted inside of a flow passage which clapper is formed by investment casting. The clapper of the check valve will only allow fluid flow in one direction. The face of the check valve has an annular groove formed therein and a recessed center portion. After a base surface is cut in the backside of the clapper, a molded rubber seal is formed on the face of the clapper with the seal extending from the annular groove with raised annular surfaces and a web covering the center portion. Upon receiving reverse flow through the check valve, the clapper will immediately close and seal against a valve surface. The raised annular surfaces deform into the annular recess therebetween allowing metal-to-metal contact between the clapper and valve surface, while simultaneously maintaining a good rubber seal contact.