DOWNHOLE ROD PUMP Russian patent published in 2012 - IPC F04B47/00 F04B53/02 

FIELD: engines and pumps.

SUBSTANCE: proposed pump comprises cylinder with suction valve, hollow plunger arranged to reciprocate therein and provided with pressure valve, and sealing device arranged between cylinder and plunger. Sealing device comprises set of split collars arranged on plunger case and with restricted axial displacement. Plunger comprises sleeves with pistons to take up spout pressure inside plunger and transmit force to split collars limited by adjusting nut from top. Tightening torque on said nut defines reaction force of split collars on cylinder walls.

EFFECT: improved operating performances.

3 dwg