RU2550633C1 - Aggregate for dual bed operation in well - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: aggregate includes lifting string, cable, liner, packers, electric immersed pump with check valve for product extraction with input unit and electric motor, a housing encasing the motor with cable and input unit and connected to the liner featuring several channels each entering a well section, pressure gauges with functional connection to aggregate control unit, switch valve with case and shutting unit, positioned downstream of the housing and connecting a well section with the housing space through respective channel. Switch valve features a stem with lengthwise channel connecting space under the valve to the housing, and the check valve is mounted in the lengthwise stem channel. The stem travels by a limited longitudinal path together with the check valve down under effect of differential pressure in the lift string and liner channel entering a well section, or up under effect of the produced fluid flow. The stem can engage with actuator that can open liner channels in turns while shutting the other channels upon each reciprocal travel of the stem.

EFFECT: enhanced efficiency of dual bed operation in a well.

5 cl, 3 dwg

Description

The invention relates to the oil industry, in particular, to downhole pumping units operating several objects simultaneously.

Known pumping unit for simultaneous and separate operation of the reservoirs (see RF patent No. 2482267, publ. 05/20/2013, bull. No. 14), containing a system for regulating the flow rate of the layers using slide valves with electric drive.

The disadvantages of the installation are the high complexity due to the presence of an additional packer, two spool valves with electric actuators, low efficiency, since the regulation of the flow rates of the layers is done by plating, low service life due to erosion by the flow of spools when studying.

The closest in its technical essence to the proposed installation contains an electric centrifugal pump, the motor and the inlet of which are placed in a casing communicated through a shank having several channels, with seams separated by packers, and in each channel an electrovalve is installed to connect and disconnect the seams by signal from pressure sensors installed in these channels (see RF patent No. 2339795, publ. 11/27/2008, bull. No. 39).

The disadvantage of this installation is the design complexity due to the need to install a valve with a cable for supplying power to them.

The technical problems solved by the proposed installation are to simplify and reduce the cost of the design by eliminating the electric or hydraulic valves and lines for controlling them.

These technical problems are solved by a unit for simultaneous and separate operation of formations in a well containing a string of lift pipes, a cable, a liner, packers installed outside the liner between the formations and disconnecting the well into sections, an electric submersible pump with a non-return valve for pumping formation products with an input module and an electric motor , a casing enclosing an electric motor with a cable and an input module and communicated with a shank equipped with several channels, each of which is connected to one of the sections wells, manometers, functionally connected with the installation control unit, a switching valve with a body and a shutoff body located below the casing and providing communication of one of the sections of the well with the casing cavity through the corresponding channel.

New is that the switching valve is equipped with a piston with a longitudinal channel communicating the space under the valve with the casing, and the check valve is installed in the longitudinal channel of the piston, and the piston is made with the possibility of limited longitudinal movement together with the check valve down under the action of the differential pressure in the column of lift pipes and the liner channel in communication with one of the sections of the well, or upward under the action of the pumped fluid flow, while the piston is made with the possibility of interaction with the performer nym mechanism to alternately open one of the shank channel, overlapping the other, for each reciprocating movement of the piston.

Also new is the fact that the piston is spring loaded upward.

Also new is the fact that the actuator is made in the form of a cylinder with a curly groove closed along the perimeter, interacting with a pin on the sleeve of the shut-off element of the switching valve.

Also new is the fact that the shut-off element of the switching valve is made coaxially with the piston with a longitudinal hole, which is communicated from above with the piston longitudinal channel, and from the bottom with one of the shank channels.

It is also new that the switching valve is made in the form of a shaft with a longitudinal hole, which is connected to the longitudinal channel of the piston from above, and transverse holes are made in the shaft walls with the possibility of alternating communication with the corresponding channel of the shank with each rotation of the shaft associated with the actuator.

The essence of the invention lies in the fact that the differential pressure between the cavity of the elevator pipes and the cavity of the channel of the shank is used to drive the shutoff valve of the switching valve.

Figure 1 shows the installation diagram, figure 2 is a variant of the installation diagram, figure 3 is a figured groove.

The installation of FIG. 1 contains an electric submersible pump 1 with an input module 2 and an electric motor 3, to which an electric cable 6, placed along the column of elevator pipes 7, a shank 8 with pipe channels 9 and 10, is connected through a sealed cable entry unit 4 on the casing 5 which are manometers 11, functionally connected to the control unit (not shown) by the pump 1. Channels 9 and 10 are each communicated with their own section of the well 12 containing the objects of operation - (reservoir) 13 upper and lower 14, separated by packer 15. Switching channels 9 or 10 wasps Provides a switching valve 16, including a housing 17, spring-loaded spring 18, a piston 19 with a longitudinal channel 20, equipped with a check valve 21 and a protrusion 22 in the upper part with a groove 23 that interacts with the pin 24 of the housing 17, the actuator 25 in the form of a figured groove 26 (Fig. 3) on the lower protrusion 27 (Fig. 1) of the piston 19, which interacts with the pin 28, on the sleeve 29 of the locking member 30, made with an opening 31 communicated from above with the channel 20 of the piston 19, and from the bottom with one of the channels 9 or 10 shank 18.

The installation in figure 2 contains the same basic structural elements as in figure 1, but differs in the design of the shut-off element 30 of the valve 16. To the sleeve 29 is connected a shaft 32 sealed in the housing 17 with a central channel 33 plugged by a plug 34 in the bottom parts.

Two through radial holes are made in the shaft: one 35 - with the possibility of coincidence in one of the positions of the shaft 32 with the channel 10 made radially in the wall of the housing 17, and the other 36 - with the possibility of coincidence in the other position of the shaft 32 with the channel 9, also made in casing wall 17.

Channel 9 is in communication with the cavity of the shank 8.

The installation works as follows.

After starting the electric motor 3 (Fig. 1), fed through a cable 6, introduced through a sealed input 4 into the casing 5, the submersible electric pump 1 starts pumping liquid, which from the lower sub-packer section of the well 12, in communication with the reservoir 14, enters through the shank 8, channel 9 the housing 17 of the switching valve 16, the channel 31 of the locking element 30, the channel 20 in the piston 19, opening the check valve 21, through the cavity of the casing 5 and the input device 2 to receive the pump 1, which is pumped through the column of elevator pipes 7 at the mouth (in Fig. not shown) wells 12 and further e to the collection system. Channel 9 is communicated through a liner 8 with a well section 12 located under the packer 15, pump 1 draws fluid from there, lowering the bottomhole pressure at the lower reservoir 14. When the bottomhole pressure reaches the set minimum value, the pressure sensor 11 instructs the control unit to stop the engine 3 of the submersible pump 1. Since the fluid pressure in the column of elevator pipes 7 is greater than the bottomhole pressure, the check valve 21 closes, blocking the channel 20, and the piston 19 moves downward under the influence of this differential pressure. In this case, the pin 24, moving along the groove 23 of the upper protrusion 22 of the piston 19, prevents the rotation of the piston 19, and the pin 28 of the lower protrusion 27 drives the actuator 25, moving along the curly groove 26 (figure 3), it rotates the sleeve of the locking member 30 (figure 1) 180 °, the hole 31 of which is aligned with the channel 10.

After a sufficient time has elapsed for pin 28 to reach the upper point of the figured groove 26 (Fig. 3), the control unit starts the engine 3 (Fig. 1) of pump 1, which, through channel 10, hole 31, channel 20 pumps fluid from the upper over-packer section of the well 12 and, accordingly, from the reservoir 13 through the elevator pipes 7 at the wellhead 12. The check valve 12 opens, and the piston 19 returns to the upper point under the action of the fluid flow and the spring 18, while the pin 28 moves along the figured groove 26 (Fig. 3 ), without rotating the sleeve 29 (Fig. 1), to the starting point figure following the inclined portion of the groove 26.

While the pump 1 pumps up liquid from the upper formation 13, in the sub-packer part of the formation, liquid accumulates from the lower formation 14, the bottomhole pressure near it increases, and near the upper formation 13 the bottomhole pressure decreases as the fluid is pumped out.

After the bottomhole pressure of the upper layer reaches its minimum value, the pressure gauge 11 gives the command to stop the engine 3. Everything is repeated, as in the previous cycle: the piston 19 goes down, the shut-off element 30 is rotated 180 °, the hole 31 is aligned with the channel 9 communicated with the lower layer 14. Then the control unit starts the engine 1, the piston 19 rises and everything repeats again. The control unit records and summarizes the operating time of pump 3 for each formation, taking into account the readings of the wellhead flow meter, which allows you to determine the production volumes for each of the layers per day or any other period of time.

The operation of the installation of figure 2 is slightly different from the previous one. The work begins, as shown in figure 2, with pumping from the lower reservoir 14. In this case, the fluid from the reservoir 14 flows along the shank 8, channel 9, hole 36, channel 33 of the shaft 32. The plug 34 prevents direct fluid from the liner into the channel 33 After the command of the pressure gauge 11 and the stop of the operation of the pump 1 and the operation of the entire mechanism, the sleeve 29 rotates the shaft 32 through 180 ° and the hole 35 coincides with the channel 10 communicated through the upper (over-packer) part of the well 12 with the upper formation 13, and when the engine 3 of the pump is turned on 1 last starts pumping fluid from n st.

When bottomhole pressures at the upper formation 13 are reached at the minimum value, the upper pressure gauge 11 instructs the control unit to stop the engine 3 of pump 1. The valve 17 switches again to pump out from the lower formation 13. Then, the cycles are repeated.

It should be noted that the simplest algorithm of the installation is shown. If the time to reach the minimum bottomhole pressure at the reservoirs is very different, then it is possible to add switching (engine shutdown) to the algorithm of the control unit, additionally performed upon reaching the maximum bottomhole pressure at the reservoir where accumulation occurs.

For example, the lower layer has an accumulation volume limited by the packer 15, therefore, the increase in bottomhole pressure is faster and, while the fluid is being pumped out of the upper layer 13, switching to the lower layer 14 can occur several times.

If the bottomhole pressure in none of the layers has reached the maximum value, the pump may not turn on until one of them reaches the maximum bottomhole pressure.

Pump capacity should be higher than the sum of reservoir productivity.

When working with more than two number of layers, there may be algorithms and corresponding changes in the design of the installation, ensuring the constant operation of one of the layers, while others will periodically be connected-disconnected.

Thus, the proposed installation allows you to organize simultaneous and separate operation of several layers by alternately pumping their products without the use of electric or hydraulic valves and lines to control them, which allows to simplify and reduce the cost of the design as a whole.

Claims (5)

1. Installation for simultaneous and separate operation of the layers in the well, containing a column of elevator pipes, a cable, a liner, packers installed outside the liner between the layers and disconnecting the well into sections, an electric submersible pump with a check valve for pumping formation products with an input module and an electric motor, a casing covering the electric motor with a cable and an input module and communicated with a shank equipped with several channels, each of which is connected to one of the sections of the well, pressure gauges, functionally connected associated with the installation control unit, a switching valve with a casing and a shutoff body located below the casing and providing communication of one of the sections of the well with the cavity of the casing through the corresponding channel, characterized in that the switching valve is equipped with a piston with a longitudinal channel communicating the space under the valve with the casing, and the check valve is installed in the longitudinal channel of the piston, and the piston is made with the possibility of limited longitudinal movement together with the check valve down under the action of the differential abnormalities in the tubing string and liner channel, connected with one of the sections of the well, or upward under the action of the pumped fluid flow, while the piston is made with the possibility of interaction with the actuator, which allows to open one of the liner channels one by one, overlapping the others, each time translational movement of the piston. 2. Installation for simultaneous-separate operation of the layers in the well according to claim 1, characterized in that the piston is spring-loaded upward. 3. Installation for simultaneous and separate operation of the layers in the well according to claim 1 or claim 2, characterized in that the actuator is made in the form of a cylinder with a curly groove closed along the perimeter, interacting with a pin on the sleeve of the shut-off element of the switching valve. 4. Installation for simultaneous and separate operation of the layers in the well according to claim 3, characterized in that the shut-off element of the switching valve is made coaxially with the piston with a longitudinal hole, which is connected to the longitudinal channel of the piston from above and from one of the shank channels from below. 5. Installation for simultaneous and separate operation of the layers in the well according to claim 3, characterized in that the switching valve is made in the form of a shaft with a longitudinal hole, which is communicated from above with the longitudinal piston channel, and transverse holes are made in the shaft walls with the possibility of alternating communication with the corresponding channel of the shank at each rotation of the shaft associated with the actuator.

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