BORE-HOLE PLUNGER PUMP Russian patent published in 2011 - IPC F04B47/04 

FIELD: engines and pumps.

SUBSTANCE: bore-hole plunger pump includes housing, pump chamber with suction valve and which is interconnected by means of pressure valve to tubing string. Control chamber with drive liquid is separated by means of partition from pump chamber. Cavity filled with buffer liquid so that hydraulic seal is formed is located between pump chamber and control chamber. Lower part of plunger connected by means of stock to string of rods is located in control chamber. Upper part of plunger is arranged in separating chamber. The latter is formed above the control chamber and separated from it with cylinder at least with one circumferential seal enveloping the plunger and filled with parting liquid separated from pumped liquid in tubing string by means of freely moving separator which is sealed with external and internal circumferential seals relative to inner wall of housing and stock.

EFFECT: improving operating reliability of bore-hole plunger pump and enlarging the overhaul period of its operation.

1 dwg, 7 cl