| 摘要 |
In a pump having a cylinder liner, there is a piston therein, a seal around the piston and rear wearband around the piston body to align the piston within the liner. An elastomeric seal ring is in sealing and sliding contact with the liner. A gap filler, with minimal axial creep and controlled radial creep, abuts the rear surface of the seal and maintains continuous contact with the liner thereby continuously closing the extrusion gap between the gap filler and the liner as the liner wears. The wearband has a plurality of angled grooves longitudinally traversing it. Abrasive particles are directed within and through the grooves in the wearband while a source of liquid is communicated into the piston body, through water channels in the gap filler and through the flowpaths in the wearband to create a vortex action which washes the liner wall. The wearband insures no metal to metal contact between the piston and liner and provides a constant piston gap between the metal piston and liner. A thin seal ring improves the temperature gradient within the ring, controls the creep of the ring, reduce the axial load on the ring and allows rear removal of the ring without removing the piston from the liner. |
