SU1420240A1 - Deep-well sucker-rod pump - Google Patents

Abstract

The invention relates to a technique for extracting oil and permits an increase in the volumetric efficiency of the pump by eliminating losses due to leakage of liquid in a pair of plunger-cylinder. A differential hollow plunger 2 is installed in the stepped cylinder 1, the lower stage 4 of which is equipped with a radial channel 6. The channel is equipped with a check valve 8 installed so that it can open when the plunger moves downwards, while the suction valve 7 is located in a smaller cylinder stage. When the plunger moves upward, the leakage of fluid from the upper stage accumulates in the annular chamber 5, and during the piston stroke downward, it is forced out through the channel into the plunger cavity. 1 il.

Description

The invention relates to the technique of oil testing, in particular, to a well sucker rod pump, and can be used in the oil industry when pumping formation fluids from wells.

The purpose of the invention is to increase the volumetric efficiency by eliminating losses due to fluid leakage in a plunger-cylinder pair.

The drawing shows the described pump.

The downhole sucker-rod pump contains a stepped cylinder 1, a differential hollow plunger 2 installed in a stepped cylinder, with a discharge valve 3, the lower stage 4 of which is located in the cylinder 1 to form an annular chamber 5 and is equipped with at least one radial channel 6, which connects the annular chamber 5 to the cavity a differential piston 2, and a suction valve 7,

The radial channel 6 is additionally provided (with a check valve 8 installed with the possibility of its opening during the course of the differential plunger 2 down, while the suction valve 7 is located in a smaller stage 9 of the cylinder 1.

Well sucker rod pump works as follows.

When the differential hollow plunger 2 moves upward due to the difference in the plunger and cylinder sections in the pump, an annular chamber 5 is formed, with the discharge 3 and the additional non-return valve 8 being closed, and the liquid is sucked into the sub-plunger cavity (not indicated) of the smaller cylinder 1 of the pump through the opening suction valve 7. At this time, the leakage of fluid from the upper stage (not indicated) of a pair of differential polom plunger 2 — the stepped cylinder 1 of the pump accumulates in the annular chamber 5, the volume of which is selected c. so that it is always greater than the volume of fluid flowing through the gap of the pair when the differential hollow plunger moves upwards. This prevents the transfer of a pressure equal to the high I e C-ol Oa liquid in the column of pump tubes (not shown) to the liquid in the annular chamber 5 and to its dissipation through the gap of the lower

0

five

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0

c Q

steps (not indicated) of a pair Differential hollow plunger 2 - a stepped cylinder 1 to a smaller step 9 of a tsipindr, since the pressure in the subplunger cavity of a smaller step 9 of the cylinder is equal to the dynamic level of the fluid in the annulus of the well (not shown) and is always greater than the pressure in the annular chamber 5.

During the course of the differential hollow plunger 2 down suction, the valve 7 is closed, and the liquid from the sub-plunger cavity through the opening discharge valve 3 and the cavity of the differential plunger 2 is forced into the above plunger cavity of the larger cylinder stage of the pump and further into the column of pump tubes. As the differential hollow plunger 2 moves down due to a decrease in the volume of the annular chamber 5, the pressure in it increases and the additional 5-way valve 8 opens, passing the fluid accumulated in the chamber through the radial channel 6 into the cavity of the differential plunger 2 together with the liquid from the sub plunger the cavity of the small stage 9 of the pump cylinder into the supra plunger cavity of the larger cylinder stage and further into the column of pumping pipes.

During the subsequent operation of the pump, i.e. when the differential plunger 2 moves up and down, the cycles are repeated.

Claims (1)

Invention Formula A downhole sucker-rod pump containing a stepped cylinder, a differential hollow plunger mounted in a stepped cylinder e, with a discharge valve, the lower stage of which is located in the cylinder to form an annular chamber and supply; it is at least one radial channel, which communicates an annular chamber with a cavity of a differential plunger, and a suction valve, which is due to the fact that, in order to increase the volumetric efficiency, it is radial. the channel is additionally equipped with a check valve installed with the possibility of its opening during the course of the differential plunger down, while the suction valve is placed in a smaller cylinder stage.