OIL WELL PUMPING UNIT WITH PACKER FOR EXTRACTING OIL UNDER ABNORMAL CONDITIONS Russian patent published in 2011 - IPC E21B43/00 

FIELD: oil and gas production.

SUBSTANCE: pumping unit consists of pump and one or several packers lowered successively into well on flow string. The unit is additionally equipped with a three-position back valve installed directly above the pump. The valve consists of a case, a ball, and a hollow rod inside the case. An upper part of the rod is made in form of a seat for the ball, while under the seat there are made through radial channels on it. Further, the valve consists of a bushing above the ball, of a movable hollow rod positioned on external generatrix of the hollow rod coaxially to it and designed to shut off and open radial channels of the hollow rod. Also, the movable hollow rod is spring loaded. When the unit includes at least two packers, then there is installed a compensation valve of mechanical action between the packers in the flow string. The column for overflow of gas is positioned concentrically in the flow string; bottom of the column is connected with a unit of cross flow; or the flow string is equipped with a device for separation and injection. The unit is also furnished with a device for rigid or sliding pressure tight connection and disconnection of parts of the flow string. An upper part of the column for gas overflow is coupled with a wellhead production tree; in its cavity there are installed a pressure control or gas choke chamber.

EFFECT: raised efficiency of pumping unit for extraction of oil in wells at disorder of production well.

4 cl, 5 dwg