BOTTOMHOLE PUMP SET FOR PRODUCT LIFTING ALONG WELL FLOW STRING Russian patent published in 2009 - IPC F04B47/02 

FIELD: engines and pumps.

SUBSTANCE: invention is related to oil production industry and may be used for operation of production wells, including the ones with highly viscous produce, and also in wells of small diametre. Bottomhole pump set includes sucker-rod pump comprising cylinder, receiving valve, plunger with controlled injection valve, which is connected to string of pump rods with positioners, packer and relief device. Downstream relief device hollow tailpiece is arranged, which consists of upper and lower parts. Additional relief device is located in tailpiece. Packer is arranged in the form of self-sealing collars with distance between neighboring self-sealing collars that exceeds distance between ends of pipes in coupler joints of flow string, and support. Downstream packer and upstream support tailpiece is equipped with side holes. Additional relief device is arranged in the form of cylinder connected to lower part of tailpiece, with side channels that communicate to internal cavity of tailpiece and hollow piston connected to upper part of tailpiece, with the possibility of limited axial displacement downwards relative to cylinder with tight overlapping of connection between side channels of cylinder and internal cavity of tailpiece.

EFFECT: provides for considerable reduction of laboriousness of installation -dismantling and makes it possible to reduce time required for set lowering-lifting in well, and also to expand field of its application due to possibility to use it in wells of small diametre.

2 dwg