OIL-WELL SUCKER-ROD PUMP Russian patent published in 1995 - IPC

FIELD: oil industry. SUBSTANCE: sucking valve is mounted at the bottom part of the cylinder. The valve has housing, seat, and valving member. The plunger and delivery valve are positioned inside the space of the cylinder. The plunger consists of the rod having stop collar and nut mounted on the rod and connected with a tie member, bushing sections with faces having spherical guide surface, and flexible ring seals interposed between the sections for permitting a contact of the cylinder surface with its outer cylindrical surface and the spherical surfaces of the sections with its face surfaces. The rod is positioned inside the sections and flexible seals at their axis and connected with the tie member. The collar and nut, which are in contact with the face surfaces of the end sections, have openings made along their axes. EFFECT: enhanced efficiency. 2 cl, 1 dwg