OIL-WELL PUMPING UNIT FOR OIL EXTRACTION AND WATER PUMPING INTO STRATUM Russian patent published in 2009 - IPC E21B43/14 E21B43/38 

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to gas-and-oil producing industry, particularly to winning of water-cut oil and utilisation of produced water. Unit includes packer, installed between top and bottom stratums, top and bottom pumps with worm shafts, blown down on tubing string into well and installed higher than packer, pumps drive, located on surface. Inlet of bottom pump is located lower than dynamic head of water precipitated under action of gravitation from water-oil mixture of top stratum. Outlet of this pump is communicated to under-packer space. Additionally inlet of top pump is located higher than dynamic head of precipitated water, and outlet is communicated to tubing string. Between worm shafts it is installed reducer, input shaft of which is connected to bottom of top worm shaft, and outlet - with top of bottom worm shafts of pumps. Reducer body is rigidly connected to pipe lift string, and its gear ratio is selected so that correlation of efficiency of top and bottom pumps corresponds the amount correlation of supply into well of water and oil with condition of providing of gravity separation of water-oil mixture of top stratum at opposite rotation of worm shafts. Pipe lift string is implemented with ability of rotation under action of additional drive, located on surface.

EFFECT: design simplification, lighting of service and regulation ensured by placement of drive on wellhead, and also fitting simplification of pumps of required efficiency subject to water cut of top stratum products.

1 dwg