RU2381352C1 - Borehole pumping unit for two reservoirs simultaneouse production - Google Patents

Abstract

FIELD: oil- and gas industry.

SUBSTANCE: invention related to oil-and gas industry, particularly to borehole pumping unit for two reservoirs simultaneous production. The borehole pumping unit contains tubing string, cable, parker, installed between reservoirs, tail, by-pass device which can be opened under pressure, top- piston with bas string and bottom- electro-submersible with electrical motor pumps for the corresponding reservoirs product withdrawal, pumps covered with top and bottom jackets. Electrical submersible pump bottom jacket equipped with a cable sealing unit and connected to under-parker clearance from the bottom via the tail. The electrical submersible pump outlet connected with the top jacket via fitting, which connected form the top with the tubing string and a side channel, connecting top pump inlet with above-parker clearance. The electrical submersible pump equipped with measurement block form the bottom, executed with ability to transfer data via cable. The top jacket executed as a sleeve with an additional longitude channel, equipped with a process pipe, fixed on top of the top jacket and connected with the tubing string from above, and from the bottom - with the side channel, equipped with safety return valve. The fittings connecting the bottom pump outlet to the tubing string via top jacket lateral channel, also equipped with additional return well, above which the by-pass unit located. The bottom jacket equipped with elbow with cable sealing unit and a process channels, installed between the bottom pump and electrical motor in a way that the pump inlet connected to the bottom jacket via process channels. Plunger pump executed as a insert one with ability of hermetic interaction with the top jacket process fitting internal surface. The measurement block equipped with damping centraliser, which interacts with the bottom jacket.

EFFECT: pump alternate operation ability, avoiding fluid spilling during their lifting, avoiding operation failure and the bottom pump early failure, application of a different combination of electrical motors and electrical submersible pumps, creation part load regime of the bottom reservoir operation.

2 dwg

Description

The invention relates to the oil industry, in particular to downhole pumping units for the simultaneous separate operation of two reservoirs.

A well-known sucker rod pumping unit for the simultaneous operation of two layers in a well containing a column of elevator pipes, a column of rods, a packer, a liner and a differential pump. Moreover, the suction and discharge valves of the upper section of the pump are installed on the side of the cylinder, and a self-sealing packer is placed between them (book Simultaneous separate operation of multilayer oil fields / R.A. Maksutov, B.E.Dobroskok, Yu.V. Zaitsev. - M: “ Subsoil ", 1974. - Page 89, Fig. 54). This installation produces a separate rise in the production of formations: the bottom - along the string of elevator pipes, the top - along the production casing of the well.

The disadvantages of the installation are: complex design, the inability to study the reservoirs during operation (determination of bottomhole and reservoir pressures), if it is necessary to remove the pump, it rises with the upper packer, which contributes to its wear and reduction of the reliability of the installation, in addition, as a result of the “piston” the effect created by the packer during the rise, there is a spill of products from the production casing of the well. The location of the suction valve of the upper section of the pump under the packer, and the discharge valve above the packer increases the harmful space of the pump, which reduces its performance. In addition, the installation has a low productivity of pumping out the products of the lower layer due to limitations in the diameter of the plunger of the lower section, which, based on the principle of the differential pump, must have a diameter smaller than the diameter of the plunger of the upper section. Another disadvantage of the installation is that the differential pump is driven by one column of rods and there is no possibility of separate regulation of the performance of the lower and upper sections of the pump.

Also known is a downhole pumping unit for the simultaneous operation of two layers in a well, comprising a column of elevator pipes, a packer, a liner and two separate electric centrifugal pumps with separate cables supplying the products of the upper and lower layers to one column of elevator pipes, through which it is supplied to the surface, production of the lower reservoir is fed by the lower pump to the column of elevator pipes but to the bypass casing, in which a channel is made for communicating the reception of the upper pump with the over-pack space of the well (books ha "Simultaneous separate exploitation of multilayer oil fields" / R.A. Maksutov, B.E. Dobroskok, Yu.V. Zaitsev. - M .: "Nedra", 1974. - Pages 106-107, Fig. 63a).

The disadvantage of the installation is that it does not allow a separate rise and measurement of the production rate of each of the layers. Other disadvantages of the installation are: the complexity of installation at the well, the bulkiness of the equipment (the total length of the installation can reach 30-35 m), the difficulty of lowering two cables simultaneously into the well, in addition, due to the presence of two cables, the probability of insulation failure and failure of the installation increases , not resolved issues of the study of disparate formations. Also, this installation does not allow the use of various combinations of electric motors and pumps, since their standard sizes are incorporated in the manufacture.

Closest to the technical nature of the proposed installation is a "Pump installation for simultaneous separate operation of two layers in the well" (patent RU No. 2291953, IPC EV 43/14, 47/00, publ. 20.01.2007 Bull. No. 2), containing a column lift pipes, a cable, a packer, a liner and two separate pumps for pumping out the formation products, which are enclosed in the upper and lower shells, the pump for pumping out the products of the lower layer being made electric submersible, while the lower casing of the electric submersible pump is equipped with a cable sealing unit and communicated from the bottom with the under-packer space through the liner, which is equipped with a bypass device above the packer, with the possibility of providing hydraulic communication between the over-packer space of the well and its under-packer space through the liner when the pressure of the bypass device is reached in the well, the outlet of the electric submersible pump communicating with the upper casing, which is connected to a column of elevator pipes and is equipped with a side channel, while the upper pump is made by a rod, the column of rods of which is hollow sealingly connected with plunger sucker rod pump, the intake of the pump through a side channel in communication with the space nadpakernym and submersible pump from the bottom may be equipped with a pressure sensor adapted to transmit via cable submersible pump information.

The disadvantages of this installation are the constructive impossibility of using an plug-in plunger pump, which complicates the process of removing and repairing this pump (this is possible only with a column of elevator pipes), the inability to stop if necessary (for example, the performance of this pump significantly exceeds the productivity of the lower layer) of the electric submersible pump, since the output of this pump also does not have the ability to cut off the column of elevator pipes from the in-pipe space, while lower of the first layer at the inlet of the electric submersible pump, a reduced pressure is created and the gas contained in the products of the lower layer is released, which can lead to failure of its operation when the upper part of the lower casing is filled and the input of the electric submersible pump is reached, and it is impossible to lift the hollow rods and the tubular lift pipes without spilling liquids in them, which worsens the working conditions of the service crews, while this installation does not allow the use of various combinations of electric motors and pumps , since their standard sizes are laid down during manufacture, and a pressure sensor subject to constant vibrational loads of the electric motor has a large dispersion of readings, which leads to the removal of inaccurate information and can lead to rapid flooding of the productive lower layer due to incorrectly selected selection modes.

The technical task of the invention is to provide the possibility of alternating operation of the pumps and the possibility of using an plug-in plunger pump due to the installation of valves in the side channel of the upper casing and between the column of elevator pipes and the outlet of the electric submersible pump to simplify installation and maintenance of the installation, as well as to exclude the possibility of spilling liquid when lifting pumps, providing a preliminary discharge of fluid into the well, and disruption of the lower pump, ensuring the selection of gases from the upper space of the lower about the casing, installing an sub, which is part of the lower casing, between the electric motor and the electric submersible pump, while expanding the installation functionality due to the possibility of combining different types and types of electric submersible pumps and electric motors thanks to the use of the sub installed between them, with the possibility of choosing a more gentle mode selection from the lower reservoir due to a more accurate removal of the parameters of this reservoir due to the reduction of vibration loads on the measurement unit t electric motor.

The technical problem is solved by a borehole pumping unit for simultaneous separate operation of two layers containing a lift pipe string, a cable, a packer installed between the layers, a liner, a pressure relief device, the upper one is a plunger with a rod string and the lower one is an electric submersible pump with an electric motor for pumping the products of the corresponding layers, which are enclosed in the upper and lower casings, the lower casing of the electric submersible pump equipped with a cable sealing unit and communicated from below with with an odnopakerny space through the shank, and the output of the electric submersible pump is communicated by a pipe with an upper casing, which is connected to the column of elevator pipes from above and is equipped with a lateral channel communicating the input of the upper pump with an above-packer space, while the electric submersible pump is equipped with a measuring unit, which is capable of transmitting information cable submersible pump.

New is that the upper casing is made in the form of a sleeve with an additional longitudinal channel, equipped with a technological pipe mounted on top of the upper casing and communicated from above with an elevator pipe string, and from the bottom with a side channel that is equipped with a safety non-return valve, and a pipe communicating the outlet the lower pump with a column of elevator pipes through the longitudinal channel of the upper casing, is also equipped with an additional check valve, above which a bypass device is located, while the lower casing is equipped with a top an sub with a cable sealing assembly and technological channels installed between the lower pump and its electric motor so that the input of this pump is communicated by means of technological channels with the lower casing, the plunger pump being made plug-in with the possibility of tight interaction with the inner surface of the technological branch pipe of the upper casing, while the measurement is equipped with a damping centralizer interacting with the lower casing.

Also new is the fact that under the packer a device is installed for venting gas from under the under-packer space to the liner.

Figure 1 - the upper part of the installation with the upper layer.

Figure 2 - the lower part of the installation with the lower layer and the packer.

A downhole pump installation for simultaneous separate operation of two layers, containing a column of elevator pipes 1 (Fig. 1), cable 2, packer 3 (Fig. 2), installed between the upper 4 (Fig. 1) and lower 5 (Fig. 2) layers , shank 6, bypass device 7, opening from overpressure, upper 8 (figure 1) - plunger with rod string 9 and lower 10 (figure 2) - electric submersible pumps with electric motor 11 for pumping the products of the corresponding layers 4 (figure 1) ) and 5 (figure 2), which are enclosed in the upper 12 (figure 1) and lower 13 (figure 2) casings, the lower casing 13 of the electric submersible pump 10 is equipped with a cable sealing assembly 14 and communicated from below with the under-packer space 15 through the shank 6, and the output of the electric submersible pump 10 is communicated by a pipe 16 with an upper casing 12 (Fig. 1), which is connected to the column of elevator pipes 1 from the top and is provided with a side channel 17, communicating the input of the upper pump with the puffer space 18. The electric submersible pump 10 (Fig. 2) is equipped with a measuring unit 19, which is capable of transmitting information via cable 2 of the electric submersible pump 10. The upper casing 12 (Fig. 1) is made in Ideas of a sleeve with a lateral 17 and longitudinal 20 channels, equipped with a technological pipe 21 fixed on top of the upper casing 12 and communicated on top with the pipe lift string 1, and on the bottom with the side channel 17, which is equipped with a safety non-return valve 22. A pipe 16 communicating the output of the lower pump 10 (figure 2) with a column of elevator pipes 1 (figure 1) through the longitudinal channel 20 of the upper casing 12, is also equipped with an additional check valve 23 (figure 2), which prevents leakage through the pump 10, above which the bypass device 7 is located. Lower casing 13 Top mounted with a sub 24 with a cable sealing unit 15 and technological channels 25. A sub 24 is installed between the lower pump 10 and its electric motor 11 so that the input of this pump 10 is communicated by means of the technological channels 25 with the lower casing 13. The plunger pump 8 (Fig. 1) made plug-in with the possibility of tight interaction with the inner surface of the pipe 21 of the upper casing 12. The measurement unit 19 is equipped with a damping centralizer 26 (made in the form of a filter with an elastic cuff outside - figure 2 or spring centralizers and etc., not shown in FIG. 2) interacting with the lower casing 13.

Downhole pumping unit for simultaneous separate operation of two layers works as follows.

In the well 27, a packer 6 (for example, PRO-YAT-O-122 with an anchor unit manufactured by the Packer NPP, Oktyabrsky) is installed between the layers 4 (FIG. 1) and 5 (FIG. 2) with a subpacker installed from below layout 28 (for example, a filter (figure 2), an additional hvotovik, dispenser, sump and / or the like - not shown in Fig.) through the longitudinal channel for the shank 6. Depending on the performance and depth of the lower layer 5 select pump 10 (the higher the productivity of the formation, the more productive the pump 10 should be) and its electronic motor 11 (the deeper the bedding interval 5, the more powerful the electric motor 11 should be. Then, the adapter 24 selected for the selected lower pump 10 and electric motor 11 is connected with the electric motor 11 through the sealing assembly 14 of which I pull the cable 2 with subsequent insulation ( for example, using an elastic cuff clamped by a hollow nut (or splice) - not shown in FIG. 2). An electric motor 11 with a measuring unit 19, equipped with a damping centralizer 26 to remove vibration and prevent damage to the cable extension, put on the bottom casing 13 from the bottom from below, tightly fixing it from above on the sub 24 (for example, using a thread). Then, the liner 6 is lowered into the well and the liner 6 is attached with the lower casing 13. Then, the lower pump 10 is attached to the sub 24 (for example, by a flange connection, not shown in Fig. 2), to which an additional non-return valve 23 and a bypass device are sequentially connected from above. 7 with a pipe 16, hermetically attached from the bottom to the upper casing 12 (figure 1). Next, from above, to the upper casing 12, equipped with a safety non-return valve 22 in the side channel 17 and the process pipe 21, connect the column of elevator pipes 1, on which the entire structure is lowered into the well 27 until the longitudinal interaction of the longitudinal channel of the packer 3 (Fig. 2) with the shank 6 This is ensured by the latch (shown conditionally above the packer) of the shank 6, which rests on the packer 3, is fixed and sealed in it, and the weight loss of the installation is recorded on the wellhead weight indicator (not shown in FIG.).

After that, the mouth is equipped with wellhead fittings (not shown in FIG.) With sealing of the cable outlet and with the possibility of longitudinal movement of the rod string 9 through the wellhead stuffing box (not shown in FIG.). The column of rods is attached to the wellhead drive (for example, the rocking machine is not shown in FIG. 1), and the cable 2 to the control station (not shown in FIG.).

To start the installation, a voltage is applied via cable 2, under the action of which the electric motor 11 (Fig. 2) is driven, the rotor of the pump 10 is rotated. As a result, the production of the lower layer 5 from the under-pouch space 15 through the under-packer arrangement 28, the shank 6, the lower casing 13 and the technological channels 25 of the sub 24 emerges at the inlet of the lower pump 10, which pumps the incoming products through the pipe 16 through an additional valve 23 and the longitudinal channel 20 (Fig. 1) of the upper casing 12 into the pipe lift string 1.

When this column of rods 9 using the drive give a reciprocating motion, which is transmitted to the plunger 29 of the upper pump 8. As a result, the production of the upper layer 4 from nadpakerny space 18 through the side channel 17 and the safety valve 22 enters the process pipe 21 and the input of the upper pump 8, which pumps this product into the column of elevator pipes 1, where it is mixed with the products of the lower layer 5 (Fig. 2).

According to the tubing string 1 (FIG. 1), the production of the layers 4 and 5 (FIG. 2) by means of the corresponding pumps 4 (FIG. 1) and 5 (FIG. 2) is understood to the surface.

When starting the installation, it is recommended to first start the lower pump 10 to raise the liquid level inside the column of elevator pipes 1 (Fig. 1), to crimp the entire elevator layout and stuffing box seals.

Due to the fact that the technological channels 25 (FIG. 2) of the sub 24 communicate with the input of the lower pump 5 with the top of the lower casing 13, the gas released does not accumulate in it, because it is taken together with the incoming products of the lower layer 5. This eliminates the situation of failure or failure of the lower pump 10 due to the capture of accumulating gas.

In cases of disruption (unauthorized removal) of the upper pump 8 (Fig. 1) from the process pipe or when removing the upper pump 8 for prevention, repair or replacement (so the life of the plunger pumps is lower than the electric submersible ones), the safety valve 22 eliminates the ingress (crushing) of liquid from the lift column pipes 1 through the lateral channel 17 and the puffer space 18 into the upper layer 4, since in the column of elevator pipes 1 the liquid level supported by the pumps 8 and 10 (FIG. 2) is higher than the hydrostatic pressure of the upper layer 4 (FIG. 1). At the same time, production of the lower formation 5 (Fig. 2) by the lower pump 10 can continue after sealing the wellhead 27.

To conduct studies of the lower layer 5, the electric motor 11 and the lower pump 10 are temporarily stopped. The signals of the measuring unit 19, which are transmitted to the surface via cable 2, monitor the change in bottomhole pressure and temperature (and / or other parameters) in the under-packer space 15 and construct a pressure recovery curve (HPC). The HPC processing determines the parameters of the lower layer 5. In this case, an additional valve 23 cuts off the possible impact of the liquid column of the pipe tubing string 1 (Fig. 1), transmitted through the longitudinal channel 20 of the upper casing 12 and the pipe 16 to the lower pump 10, protecting it, which is especially important at the initial moment when starting this pump 10, excluding its premature failure. The upper pump 8 (figure 1) can produce the products of the upper reservoir 4 in the normal mode.

With a large gasification of the lower layer 5 (Fig. 2) between the packer 3 and the filter 18, a device can be installed to discharge gas 30 from under the under-packer space 15 into the liner 6 (for example, a sleeve with a hole or a bypass valve that opens when a certain amount of gas is accumulated) under the packer 3, etc., are not shown in FIG. 2). This eliminates the collection of large amounts of gas released from the products of the lower layer 5 directly under the packer 3 with its subsequent passage through the filter 28, the shank 6 and the lower casing 13 to the inlet of the lower pump 10, which is unacceptable for the reasons mentioned above.

The measuring unit 19 (figure 2) can be equipped with various types of sensors (for example, a sensor for measuring fluid flow rate, water cut,% gas, etc.) for studying the characteristics of the lower reservoir 5. The presence of a damping centralizer 26 on the measuring unit 19 allows practical data to increase the accuracy of the parameters taken up to 10%, which allows you to more accurately adjust the operating mode of the lower pump 10 and increase the selection of production of the lower reservoir 5 to 8% before its flooding.

To conduct studies of the upper formation 4 (Fig. 1), the upper pump 8 is temporarily stopped together with the lower pump 10 (Fig. 2) and in the usual way remove the HLF in the over-packer (annular) space 18 (Fig. 1) of the well 27, the processing of which determines the parameters upper layer 4.

During operation, if necessary, any of the pumps 4 (figure 1) or 5 (figure 2) can be stopped, while the other pump 5 or 4 (figure 1) can work in normal mode, due to the presence of check valves 22 and 23 (figure 2).

To remove the installation from the well 27, first, an excess pressure is created in the pipe string 9 to open the bypass device 7 (for example, the safety membrane is destroyed) (Fig. 2), as a result, the liquid level in the pipe string 1 (Fig. 1) is equalized with the liquid level inside the well 27. Then the wellhead reinforcement is disassembled, the plug-in plunger pump 8 with the rod string 9 is removed. Since the rod string 9 is not hollow, there will be no liquid outflow at the wellhead. By raising the elevator pipes 1 (Fig. 1), the entire installation is removed to the surface. Since the liquid will flow out of the installation through the open bypass device 7 (figure 2), there will be no outflow of liquid at the mouth, which makes the extraction of the installation more convenient for maintenance personnel. Disassembly of the installation is carried out in the reverse assembly sequence. Then, if necessary, a pipe string with a puller is lowered (not shown in FIG.), With which, after interaction and capture, the packer 3 (FIG. 2) is brought out of the working position into the transport position (unpacked) and removed to the surface.

The sub 24 (Fig. 2) can be prefabricated from the upper and lower parts (not shown in Fig.) With various types of connections at the ends for ease of selection for various types of layout of electric motors 11 and electric submersible pumps 10.

Between the electric motor 11 and the sub 24 it is possible to install a hydraulic protection (Fig. 2 is shown conventionally).

The proposed design of the well installation provides the possibility of alternating operation of pumps through the pipe string due to the presence of check valves and eliminates the possibility of liquid spill when lifting the pumps, providing a preliminary discharge of liquid into the well through a bypass device, while plug-in can be used to simplify installation and maintenance of the well plunger pump and exclude the possibility of disruption of work and premature failure of the lower pump due to the selection of ivshegosya gas from the upper space of the lower case, and also allows the use of different combinations of electrical submersible pumps and motors through the use of sub mounted therebetween, wherein due to more accurate measurements of properties of the lower layer and the lower mode selection pump increases the extraction of products from this reservoir to its flooding.

Claims (2)

1. A downhole pumping unit for the simultaneous separate operation of two layers, containing a column of elevator pipes, a cable, a packer installed between the layers, a liner, a transfer device that can open it from pressure, the upper one is a plunger with a rod string and the lower one is an electric submersible pump with an electric motor for pumping out the products of the corresponding layers, which are enclosed in the upper and lower casings, the lower casing of the electric submersible pump equipped with a cable sealing unit and communicated from below with a subpack space through the shank, and the output of the electric submersible pump is communicated by a pipe with an upper casing, which is connected to the column of elevator pipes from above and is equipped with a side channel that communicates the inlet of the upper pump with a packer space, while the electric submersible pump is equipped with a measuring unit from the bottom, which can transmit information via cable submersible pump, characterized in that the upper casing is made in the form of a sleeve with an additional longitudinal channel, equipped with a technological pipe, fixed on top of the upper casing and communicated from above with the lift pipe string, and from the bottom with the side channel, which is equipped with a safety check valve, and a pipe that communicates the output of the lower pump with the lift pipe string through the longitudinal channel of the upper casing, is also equipped with an additional check valve, above which is located a bypass device, while the lower casing is equipped on top with a sub with a cable sealing unit and technological channels installed between the lower pump and its electric motor so that the input is the first pump is communicated through technological channels with a lower casing, the plunger pump being plug-in so that it can tightly interact with the inner surface of the technological pipe of the upper casing, while the measuring unit is equipped with a damping centralizer interacting with the lower casing. 2. A downhole pumping unit for the simultaneous separate operation of two layers according to claim 1, characterized in that a device for discharging gas from under the under-packer space to the liner is installed under the packer.

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