UPLIFTING METHOD OF FORMATION FLUID, AND PUMP UNIT FOR METHOD'S IMPLEMENTATION Russian patent published in 2010 - IPC F04B47/02 

FIELD: engines and pumps.

SUBSTANCE: uplifting method of formation fluid involves lowering of suction device with plunger and valves to tubing string mounted inside casing string of the well at the fluid flowing from bottom-hole area to inter-tube and above-plunger area and from inter-tube space to inner cavity of tubing string. Plunger creates negative pressure in bottom-hole area. Forced opening and closing of plunger valve. Forced closing of above-plunger area in tubing string above plunger valve when plunger is lowered at the distance of plunger travel, and its opening when plunger is raised. Lowering - uplifting of suction device is performed by action of force on plunger. Plunger valve is kept closed at lifting and lowering of plunger, and opened and closed in forced manner when suction device is in lower position within the travel of plunger valve relative to its seat. Pump unit includes casing string, tubing string. A packer is installed in bottom-hole area. In bore of suction device there mounted is a valve. Drive traction member is arranged in tubing string and connected to suction device. Cutoff valve is mounted above plunger valve. Traction member is connected to plunger. Lower part of bottom-hole packer is equipped with support platform in which there are channels connecting inter-tube and bottom-hole space to the space below the valve. Seat of plunger valve is made in lower part of plunger. Valve is mounted in a flexible manner relative to plunger and equipped with an end stop having the possibility of contacting the support platform the length of some part of which projecting behind lower plunger surface corresponds to value of valve travel relative to its seat. Plunger has a support part to interact with elastic coupling of plunger valve, in which there made are channels connecting the space under plunger to the space above plunger.

EFFECT: excluding the possibility of overflow of uplifted fluid from inter-valve space to inter-tube space during downward plunger travel.

6 cl, 4 dwg