| 摘要 |
A reciprocating pump piston includes a piston rod which is adapted to be disposed within a cylinder. A piston hub is secured to the piston rod and is adapted to be reciprocated thereby within the cylinder. The hub includes a flange portion having a cylindrical outer periphery of slightly smaller diameter than the inner diameter of the cylinder and a generally cylindrical body portion having a diameter smaller than the flange portion. An annular piston seal ring is disposed about the hub body portion. The seal ring includes an inner leg disposed in mating relation with the body portion and an outer leg defining an annular sealing lip which yields radially inward upon insertion of the hub into an associated pump cylinder. Yielding of the outer leg is to a predetermined extent sufficient to block dislodgement of the inner leg from mounted association with the hub body portion. Also provided is an annular anti-extrusion member disposed around the hub body portion intermediate the seal ring and the hub flange portion. The hub body portion includes a circumferential groove adjacent the forward end thereof, and the seal ring inner leg includes portions which closely fit into the groove. |
