SEALING DEVICE Russian patent published in 1999 - IPC

FIELD: mechanical engineering; high pressure pumps; sealing of plungers. SUBSTANCE: device has cylinder 1, plunger 2, set of holders 3, each provided with recesses with double-acting seals 4 and axial, circular and radial channels 5 to bypass liquid. Holders are installed for axial displacement and are pressed in initial position to inlet flange of cylinder by flexible displacement compensator 6. When pump is started, pressure in cylinder 1 rises gradually, and chambers are filled providing pressure distribution in spaces between holders close to arithmetical progression which is realized only at working stroke of plunger 2. At return movement of plunger, pressure drops to value close to zero suction pressure. At this moment uncoupling of holders takes place. EFFECT: increased service life of water pump plunger sealings owing to provision of uniform wear of sealing members. 1 dwg