BOTTOM-HOLE SUCKER-ROD PUMP Russian patent published in 2020 - IPC F04B47/00 

FIELD: machine building.

SUBSTANCE: invention relates to machine building, particularly, to vertical plunger pumps with self-acting valves for transfer of highly viscous liquids containing mechanical impurities and gas, in particular to downhole sucker-rod pumps. Downhole sucker-rod pump comprises composite cylinder and plunger, comprising steps of large and small diameter connected by adapters. Plunger is arranged in the cylinder to form a variable-volume chamber between the adapters. Suction and discharge valves are installed in plunger with possibility to disconnect inner cavities of stages. Suction valve includes upper and lower seats. Locking element is made in the form of a bushing with an upper collar mating the upper seat and is installed with the possibility of limited axial movement with provision of simultaneous interaction with the seats. On inlet of delivery valve cylindrical cavity with end surface is made. Plunger is equipped with branch pipe with collar in lower part mating with bore holes and cylindrical cavity with formation of lower chamber of variable volume. In upper part of branch pipe there is at least one through radial hole with possibility of its partial coverage by cylindrical recess side surface in upper position of bushing.

EFFECT: invention can be used in oil industry.

4 cl, 6 dwg