RU2706503C1 - Pump unit for production of super-viscous oil from horizontal well - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil industry, in particular, to devices for operation of super-viscous oil wells (SVO) during development by thermal methods. Pump unit comprises centrifugal pump run in pipe string. Pump is equipped with external sealing casing made with possibility of hydraulic communication between electric centrifugal pump and shank. Shank is equipped with holes arranged evenly along perimeter in one row and assembled with length sufficient for inlet to filtration part of horizontal borehole with end in required interval of installation. Shank end is equipped with streamlined nozzle with outer diameter exceeding that of shank end. At the end of the shank there are inlet channels with total area not less than the area of passage section of the shank. Based on the temperature drops along the horizontal bore and the horizontal shaft height differences for the gas and / or steam outlet from the shank, the rows of holes are located. Total cross-section of holes in row is at least 100 times less than area of passage section of shank. First row of holes is located at distance of 0.5–15 m from casing.

EFFECT: improving reliability of a pump unit for production of super-viscous oil from a horizontal well with protection against mechanical damages and released gas and / or steam at production of super-viscous oil by thermal methods.

1 cl, 1 dwg

Description

The invention relates to the oil industry, in particular to methods for operating horizontal wells of extra-viscous oil (IOS) in the development of thermal methods.

A device is known for gas separation of a submersible electric centrifugal pump in a casing (patent for PM RU No. 184048, IPC ЕВВ 43/38, published on October 12, 2018 in Bull. No. 29), in which, for wells with a large gas factor, a submersible motor with hydraulic protection, cooled the pumped liquid is equipped with an external sealed casing, which is hermetically connected to the input module of the electric centrifugal pump and is configured to isolate the pump intake from the annulus, and lower than the sealed casing of the submersible motor The gas separator is capable of transmitting torque from the shaft of the submersible motor through an additional hydraulic protection and the input module to the gas separator shaft and is hydraulically connected to the cavity of the liner pipe string, and the input module is installed so that the degassed liquid from the gas separator output enters the central channel of the input module and exits into the cavity of the sealed casing of the submersible electric motor, while the liner is lowered from the bottom of the gas separator down to the interval of perforation of the well Agins or lower.

The disadvantage of this device is the inability to work in horizontal wellbores due to the vertical gas separator and the inability to work in wells designed to produce heated formation products, due to the lack of gas outlet along the liner.

A well-known pumping unit (patent RU No. 2076952, IPC F04D 47/02, publ. 04/10/1997 in Bull. No. 10), where a submersible pumping unit located in an inclined or straight well, containing a tubing string consisting of connected sequentially between each other sections, on the descent end of which a pump unit is assembled, assembled from a set of modular sections; current-carrying cable, and the modular sections are installed with the possibility of limited angular movement relative to the tubing and each other with protection against twisting of the housings and cable due to spring rods mounted parallel to the longitudinal axis of the pump unit; the ends of the spring rods are clamped in the openings of the hub of the housing and the union nut screwing the abutting housings, one of which has an internal bore for a sphere, an external thread for a nut and a connecting flange for a collar, and the other external sphere, a union nut, a hub with holes for the rods and a connecting flange. The shafts passing inside the modular sections of the submersible installation are connected in series with the possibility of independent angular movement, regardless of the bending of the spring rods. Fastening of connections with spring rods is carried out using clamps.

The disadvantages of this arrangement are its high cost and the addition of nodes that complicate the design itself, low reliability due to the insecurity of the cable and the inability to work in wells designed to produce heated formation products, due to the lack of gas outlet along the liner.

Also known is a submersible pump (patent for PM RU No. 44766, 04.02.2004, IPC F04D 13/10, publ., March 27, 2005, Bull. No. 9), comprising a drive motor cooled by the pumped liquid, a pump unit with a receiving screen, the drive motor with the receiving grid is provided with an additional housing along the entire drive motor and communication with the annular space occurs under the electric motor, and the additional housing is equipped with a centralizer in the lower part of the additional housing.

The disadvantages of this pump are that its use was proposed in vertical wells, as well as the absence of a liner to increase the selection point and a number of other equipment for the effective operation of the installation in the horizontal part of the wells intended for the production of super-viscous oil (IOS). This arrangement does not protect against damage to the submersible cable in the horizontal sections of the IOS wells, and does not provide efficient operation and supply of the pumping unit.

The closest in technical essence is the installation for downhole separation of oil from water (patent RU No. 2531976, IPC ЕВВ 43/38, published on 10/27/2014 in Bull. No. 30), including a tubing string with an electric centrifugal pump and a flush-return a valve lowered into the production casing of the well, the annulus above the pump for accumulating and reserving the separated oil, a separation chamber located in the lower part of the well bore under the electric centrifugal pump, a passage channel communicating the intern uby space above the pump with a separation chamber, inlets for the production of produced water, and the electric centrifugal pump is equipped with an external sealing casing, made with the possibility of hydraulic communication receiving the electric centrifugal pump with an input device located in the separation chamber, consisting of a muffled from the lower end of the shaft, divided into sections with inlets, while at the level of each inlet, the shank is equipped with a glass that performs the functions of the inlet divided water into the input device and a water trap for oil droplets, the inlet openings being arranged in a row along the liner and made with a decreasing diameter in each subsequent section upward, and the gap between the casing and the production casing of the well serves as a passage channel for oil droplets.

The disadvantages of this installation are the narrow scope due to the lack of the possibility of use in horizontal wells, since it does not provide effective work for the production of IOS by thermal methods with protection against mechanical damage and the released gas and / or steam.

The technical objectives of the alleged invention is the development of a reliable design of a pumping unit for the production of IOS from a horizontal well, which allows working in horizontal wells and during the production of IOS by thermal methods with protection against mechanical damage and the released gas and / or steam.

Technical problems are solved by a pumping unit for the production of extra-viscous oil from a horizontal well, including an electric centrifugal pump, lowered on a pipe string, equipped with an external sealing casing made with the possibility of hydraulic communication for receiving an electric centrifugal pump with a shaft equipped with holes uniformly arranged along the perimeter.

What is new is that the liner is assembled with a length sufficient to enter the filtering part of the horizontal wellbore, with an end in the required installation interval, the end of the liner is equipped with a streamlined nozzle with an outer diameter larger than the outer diameter of the liner, while inlet channels with the total area of not less than the passage through section of the liner, and based on temperature differences along the horizontal well and elevations of the horizontal well to release gas and / or steam from the tail and determine the locations of openings series arrangement manufactured with a total cross section in the range of at least 100 times less than the shank passage area, the first series of holes is situated at a distance of 0.5-15 m from the housing.

The drawing shows a diagram of a pumping unit in the well.

A pump installation for the production of super-viscous oil from a horizontal well 1 includes an electric centrifugal pump 2, lowered on a pipe string 3, provided with an external sealing casing 4, configured to provide hydraulic communication for receiving an electric centrifugal pump 2 with a shank 5, equipped with holes 6 arranged uniformly along the perimeter in one row The shank 5 is assembled long enough to enter the filtering part 7 of the horizontal shaft 8 of the well 1, with the end in the required installation interval. The end of the shank 5 is provided with a streamlined nozzle 9 with an outer diameter larger than the outer diameter of the shank 5. At the end of the shank 5, inlet channels (not shown) are located with a total area of not less than the cross-sectional area of the shank 5 to reduce the resistance to flow of the produced products of the formation 10, in which the horizontal wellbore 8 of well 1 is located. Based on the temperature differences along the horizontal wellbore 8 and elevations (not shown) of the horizontal wellbore 8 for the release of gas and steam from the liner 5, p memory location rows of holes 6, 6 ', 6' '... 6n, manufactured with a total cross section in the range of at least 100 times less than the shank passage area 5 for filtering therethrough only gas and vapor (determined empirically). The minimum area of the transverse holes 6, 6 ', 6' '... 6n is determined by the minimum diameter of the drill (usually 1.5-2 mm) and one hole 6, 6', 6 '' ... 6n in a row, and the maximum is not less than 100 times less than the cross-sectional area of the shank 5. Moreover, the number and diameter of holes 6, 6 ', 6' '... 6n in the row can be any. The first row of holes 6 is located at a distance of 0.5-15 m from the casing 4 (empirically determined) to prevent the capture of gas and steam by the pump 2.

The pump installation operates as follows.

Well 1 is drilled to the design depth (for example, to horizontal section 8), equipped with casing strings and cemented (not shown), then a horizontal section 8 is drilled with smaller diameter in formation 10 with a smaller diameter than well bore 1 with casing. A filter is installed in the drilled open hole (shown conditionally), forming a filtering part 7. Then geophysical studies are carried out to determine the height differences of the horizontal shaft 8 and its filtering part 7. After heating the formation 1 (for example, heaters, steam, including from (s) by a number of wells (s) or the like) conduct geophysical studies to determine the temperature distribution along the wellbore and / or into the well 1 lower a flexible pipe 11 equipped with an optical fiber cable with temperature sensors s (not shown) for the entire length of the horizontal section 8. Based on the readings of the sensors, determine the temperature along the horizontal barrel 8. Based on certain temperature differences along the horizontal barrel 8 and the height differences of the horizontal barrel 8 for the release of gas and steam from the shank 5, determine the location the location of the rows of holes 6, 6 ', 6' '... 6n (usually at the top points in the immediate vicinity of the maximum temperatures). The first row of holes 6 are located at a distance of 0.5-15 m from the casing 4, which, as practice has shown, guaranteed to exclude the capture of steam and gas pump 2 and significantly increases its efficiency. If you make closer 0.5 m, then it is possible for the pump 2 to capture steam and / or gas with a stream until it is released from the holes 6, and if to do further 15 m, then the pump 2 captures the steam and / or gas that is released again from the liquid. From the bottom, the shank 5 is equipped with a streamlined nozzle 9 with an outer diameter larger than the outer diameter of the shank 5 to prevent damage to the shank 5 at the entrance to the filtering part 7. The pump 2 is placed in the casing 4, which is attached to the shank 5 from the top, and on the pipe string 3 s the cable 12 attached to its body, the pump 2 is lowered into the well 1. In this case, the shank 5, due to the nozzle 9, enters the filtering part 7 of the horizontal barrel 8, having the input channels at the end in the required production interval of the formation 10. Pump 2 with a casing 4 n enter the filtering part 7 of the horizontal barrel 8, eliminating the possibility of damage to both the pump 2 with the casing and the cable 12. For the extraction of the IOS, cable 12 supplies power to the pump 2, which lifts the formation 10 passing through the pipe string 3 to the day surface passing through inlet channels and a shank 5 to the casing 4 to the inlet of the pump 2. In this case, the released steam and / or gas is discharged from the shank 5 through openings 6, 6 ', 6' '... 6n along the entire length.

The proposed pump unit for the production of super-viscous oil from a horizontal well is simple and reliable, since it allows working in horizontal wells and in the production of super-viscous oil by thermal methods with protection against mechanical damage and the released gas and / or steam.

Claims (1)

A pumping unit for producing extra-viscous oil from a horizontal well, including an electric centrifugal pump, lowered on a pipe string, equipped with an external sealing casing made with the possibility of hydraulic communication for receiving an electric centrifugal pump with a shank, equipped with holes arranged uniformly around the perimeter, characterized in that the liner assembled long enough to enter the filtering part of the horizontal wellbore, with an end in the required installation interval, end x the skeleton is equipped with a streamlined nozzle with an outer diameter larger than the outer diameter of the liner, while at the end of the liner there are inlet channels with a total area of at least the area of the liner cross-section, and based on temperature differences along the horizontal shaft and elevations of the horizontal shaft for gas discharge and / or a pair of shanks determine the location of the rows of holes made with a total cross section in the row at least 100 times smaller than the passage through section of the shank Wherein the first series of holes is situated at a distance of 0.5-15 m from the housing.

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