SUBMERSIBLE PUMPING UNIT (VERSIONS) Russian patent published in 2003 - IPC

FIELD: oil producing industry. SUBSTANCE: invention can be used in pumping units designed for lifting formation fluid with higher content of abrasives from oil wells. Proposed pumping unit contains kinematically intercoupled pumps. First pump is made in form of centrifugal pump which is mechanically coupled with shaft of common drive motor and is connected by suction branch pipe with well annulus and by delivery branch pipe, with suction branch pipe of second single-screw pump. Said single-screw pump is connected by delivery branch with pressure pipeline. Pumps are connected hydraulically in tandem. Rated delivery of centrifugal pump exceeds rated delivery of single-screw pump by valve of leaks in the latter, minimum. According to second design version, single- screw pump is installed first in pumping unit and centrifugal pump is second in turn. Pumps can be mechanically coupled by means of reduction gear. EFFECT: increased service life, enlarged range of control, provision of stability of delivery. 4 cl, 3 dwg