CN107956457B

CN107956457B - Oil extraction water control device, directional well oil extraction pipe string for well completion and well completion method thereof

Info

Publication number: CN107956457B
Application number: CN201810014750.2A
Authority: CN
Inventors: 陈彦洪
Original assignee: Beijing Heli Qidian Technology Co ltd
Current assignee: Beijing Heli Qidian Technology Co ltd
Priority date: 2018-01-08
Filing date: 2018-01-08
Publication date: 2023-09-26
Anticipated expiration: 2038-01-08
Also published as: CN107956457A

Abstract

The application discloses an oil extraction water control device, a directional well oil extraction pipe string for a dead well and a completion method thereof, wherein the water control device comprises the following components: an outer tube; the central tube is sleeved in the outer tube; the wall of the central tube is provided with a fluid through hole which is communicated with the inside of the central tube; a water control mechanism installed between the outer tube and the center tube; the water control mechanism is provided with an approximately disc-shaped rotational flow chamber, a water inlet, a water outlet and an inflow channel; the cross section of the cyclone chamber, which is vertical to the radial direction of the central pipe, is circular, and the central line of the cyclone chamber is parallel to the radial direction; the outflow port is communicated with the cyclone chamber and the fluid through hole; the inflow channel communicates the inflow port with the cyclone chamber; the inflow channel opens into the swirling chamber and causes the fluid input into the swirling chamber to form a swirling flow. The water control device can automatically adjust the generated additional resistance according to the fluid flow and the fluid physical property of the production horizon, and reduce the influence of the heterogeneity of the oil layer.

Description

Oil extraction water control device, directional well oil extraction pipe string for well completion and well completion method thereof

Technical Field

The application relates to the technical field of oilfield completion, in particular to an oil extraction water control device, a well completion oil extraction pipe string for a directional well and a completion method thereof.

Background

Along with the water content of most oil wells in the middle and later stages of development, the development effect of the oil wells is greatly influenced, the directional well is used as a main well for oil field development, and the difficult problems of high water content and low yield and low efficiency still exist in the production process after the first completion of the directional well, so that the low-efficiency directional wells are subjected to well repair and secondary completion reconstruction, thereby the live asset stock is coiled, and the oil field development effect is improved.

The conventional water plugging measures adopted at present for the directional well mainly comprise hole filling and layer changing, chemical water plugging, layered exploitation and the like, but the conventional water control and oil increasing methods have a series of problems of poor water control pertinence, high construction risk, large damage to an original exploitation reservoir, high cost, complex later management and operation and the like.

Disclosure of Invention

In view of the shortcomings of the prior art, the application aims to provide an oil extraction water control device, a directional well oil extraction pipe string used for a well and a well completion method thereof, so that the additional resistance generated by automatic adjustment according to the fluid flow and fluid physical properties of the corresponding production horizon can be reduced, the influence of the heterogeneity of an oil layer can be reduced, the inflow profile can be balanced, and the oil yield of an oil well can be improved.

In order to achieve the above purpose, the technical scheme of the application is as follows:

an oil recovery water control device comprising:

an outer tube;

the central tube is sleeved in the outer tube; the wall of the central tube is provided with a fluid through hole which is communicated with the inside of the central tube;

a water control mechanism installed between the outer tube and the center tube; the water control mechanism is provided with a rotational flow chamber, a water inlet, a water outlet and an inflow channel; the cross section of the cyclone chamber, which is vertical to the radial direction of the central pipe, is circular, and the central line of the cyclone chamber is parallel to the radial direction; the outflow port is communicated with the cyclone chamber and the fluid through hole; the outflow port is positioned on the central line of the cyclone chamber; the inflow channel communicates the inflow port with the cyclone chamber; the inflow channel opens into the swirling chamber and causes the fluid input into the swirling chamber to form a swirling flow.

Preferably, the inflow channel opens into the swirl chamber in a tangential direction of the swirl chamber.

Preferably, the ratio of the diameter of the cyclone chamber to the thickness thereof is 8-15: 1, a step of; the flatness of the inner wall of the cyclone chamber is lower than +/-0.001 mm, and the surface roughness is lower than 0.00016mm.

Preferably, the length direction of the inflow passage is parallel to the axial direction of the center tube.

Preferably, the inlet comprises a first inlet at the upper end of the water control mechanism and a second inlet at the lower end of the water control mechanism;

the inflow channel includes a first channel that communicates the first inlet with the swirl chamber, and a second channel that communicates the second inlet with the swirl chamber.

Preferably, the first inlet is directed upward, and the second inlet is directed downward.

Preferably, the side surface of the cyclone chamber provided with the outflow port is a conical surface, and the taper of the conical surface is smaller than 10 degrees; the inner wall of the outflow port is a conical surface, and the taper of the conical surface is larger than 20 degrees.

Preferably, the area of the inflow opening is larger than the cross-sectional area of the inflow passage.

Preferably, the water control mechanism is provided with an outer bonding surface and an inner bonding surface which are opposite to each other; the outflow port is positioned on the inner bonding surface; the outer joint surface is an arc surface and is jointed with the inner wall of the outer tube.

Preferably, the outer wall of the central tube is provided with a containing groove for installing the water control mechanism; the fluid through hole is arranged on the bottom wall of the accommodating groove; the inner fitting surface is fitted with the bottom wall of the accommodating groove, and the outflow port is communicated with the fluid through hole in an aligned manner; the inflow port is positioned outside the accommodating groove.

Preferably, a plurality of rectangular rectifying grooves which are uniformly distributed along the circumferential direction are arranged on the outer wall of the central tube; the length direction of the rectangular rectifying groove is parallel to the axial direction of the central tube; and each rectangular rectifying groove is internally provided with one water control mechanism.

Preferably, a sieve sleeve is sleeved outside the central tube above the outer tube; the lower end of the screen sleeve is connected with the upper end of the outer tube.

Preferably, the screen sleeve comprises a protective sleeve, a filter layer, a supporting net, a flow guiding net, a wire winding net and a framework layer from outside to inside.

A directional well completion production string comprising:

an oil pipe which can be put into the sleeve; the upper end of the oil pipe is provided with a hanging packer; the oil pipe is provided with a plurality of isolation packers below the suspension packer; the isolation packer is used for sealing and separating an oil sleeve annulus between the sleeve and the oil pipe;

the oil extraction water control device according to any one of the above; and one oil extraction and water control device is connected in series on the oil pipe between every two adjacent isolation packers.

Preferably, the suspended packer and the isolation packer are both removable completion tools.

Preferably, the well head further comprises a setting pipe column capable of being lowered into the oil pipe; the lower end of the setting pipe column is in a blocking state;

the upper end and the lower end of each isolation packer are respectively connected with a sealing cylinder; the setting pipe column is provided with two sealing rings which are respectively matched with the sealing cylinder; the pipe wall of the setting pipe column positioned between the two sealing rings is provided with a through hole; and when the sealing ring is positioned in the sealing cylinder, the sealing ring is sealed and separated up and down, so that the isolation packer is set by pressing the through hole into the setting tubular column.

Preferably, the sealing ring is in interference fit with the sealing cylinder.

Preferably, the setting pipe column comprises a sealing rod provided with the sealing ring and a plug connected with the lower end of the sealing rod; the sealing rod comprises an upper joint, a connecting rod and a lower joint; the upper end of the connecting rod is connected with the upper joint, and the lower end of the connecting rod is connected with the lower joint; one of the two sealing rings is sleeved outside the upper joint and above the connecting rod, and the other sealing ring is sleeved outside the lower end of the connecting rod and above the lower joint; the through hole is positioned on the connecting rod.

Preferably, the sealing ring is a skeleton sealing ring.

Preferably, the through hole is provided with a one-way valve.

A method of completing a well using a directional well completion production string as described in any one of the preceding claims, comprising:

an oil pipe is put into the sleeve; the oil pipe is connected with the suspension packer, the isolation packer and the oil extraction water control device;

ball throwing and pressing are carried out in the oil pipe to set the suspended packer;

lowering the setting pipe column into the oil pipe;

positioning two sealing rings of the setting pipe column in sealing cylinders connected with the upper end and the lower end of the isolation packer;

pressing into the setting pipe column, transmitting pressure to the isolation packer through the through hole, and setting the isolation packer;

and (5) checking sealing.

Preferably, a plurality of isolation packers are set in sequence from bottom to top through the setting string.

The beneficial effects are that:

in summary, the oil extraction water control device is provided with the water control mechanism, and the water control mechanism can automatically generate different resistance pressure drops according to the flow and physical property changes of the fluid at the production level, so that the dynamic adjustment of the production pressure difference at the production level is realized, and the oil extraction water control device has wider applicability. When the controlled production layer is used for producing oil, stratum fluid flows through the screen sleeve and the water control mechanism and then enters the production channel (the inside of the central tube and the inside of the oil tube), and when the flow rate of the controlled production layer is increased or a large amount of water is produced, the water control device can automatically increase reverse pressure drop, increase fluid resistance and play a role in controlling water. Meanwhile, the water control device is simple in structure, low in manufacturing cost and wide in application value.

Specific embodiments of the application are disclosed in detail below with reference to the following description and drawings, indicating the manner in which the principles of the application may be employed. It should be understood that the embodiments of the application are not limited in scope thereby. The embodiments of the application include many variations, modifications and equivalents within the spirit and scope of the appended claims.

Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments in combination with or instead of the features of the other embodiments.

It should be emphasized that the term "comprises/comprising" when used herein is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps or components.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the application, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.

FIG. 1 is a schematic diagram of a directional well completion string according to one embodiment of the present application;

FIG. 2 is a schematic view of the seal bar of FIG. 1;

FIG. 3 is a schematic view of the seal cartridge of FIG. 1;

FIG. 4 is a schematic structural diagram of an oil recovery water control device according to an embodiment of the present application;

FIG. 5 is a schematic view of the water control portion of FIG. 4;

FIG. 6 is a schematic cross-sectional view of the water control structure of FIG. 5;

fig. 7 is a perspective view of fig. 6.

Detailed Description

In order to make the technical solution of the present application better understood by those skilled in the art, the technical solution of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, shall fall within the scope of the application.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

In order to prevent the water from coning at the side bottom of an oil well, inhibit the water from flowing out from a water producing layer section, overcome the problem of early water breakthrough of the oil well and improve the oil production, as shown in fig. 4 to 7, one embodiment of the application provides an oil extraction water control device, which comprises: an outer tube 15; a central tube 23 sleeved in the outer tube 15; the wall of the central tube 23 is provided with a fluid through hole 18 which is communicated with the inside; a water control mechanism 16 provided between the outer tube 15 and the center tube 23; the water control mechanism 16 is provided with a rotational flow chamber 22, a flow inlet 19, a flow outlet 21 and an inflow channel 20; the cross section of the cyclone chamber 22 which is vertical to the radial direction of the central tube 23 is circular, and the central line is parallel to the radial direction; the outlet 21 communicates the swirl chamber 22 with the fluid through hole 18; the outlet 21 is located on the centre line of the swirl chamber 22; the inflow channel 20 communicates the inflow port 19 with the swirl chamber 22; the inflow channel 20 opens into the swirl chamber 22 and causes the fluid fed into the swirl chamber 22 to swirl.

When the water control device 6 of the present embodiment is used, as shown in fig. 1, the water control device 6 is connected in series to the oil pipe 3 (specifically, the upper and lower ends of the central pipe 23 are respectively connected to the oil pipe 3), and is located between the two isolation packers 5, and the fluid through hole 18 can convey (formation) fluid into the central pipe 23, that is, the water control mechanism 16 is in communication with the interior of the central pipe 23. Wherein, two isolation packers 5 correspond to one production layer, and each production layer corresponds to one water control device 6, so as to realize water control of different production layers.

In the production process, when the flow rate of the formation fluid is excessive or the water content is high, the formation fluid enters an annulus between the central tube 23 and the outer tube 15, then enters the cyclone chamber 22 through the inflow port 19 of the water control mechanism 16 and the inflow channel 20, the formation fluid forms high-speed cyclone in the cyclone chamber 22, and the formation fluid spirally flows to the outflow port 21 in the center of the cyclone chamber 22 in the cyclone process. According to the law of conservation of momentum, the fluid which is accelerated by the high-speed rotation of the cyclone chamber 22 can generate higher throttling resistance when passing through the central outflow port 21, so that additional pressure difference can be generated on stratum fluid, the yield of a hypertonic section is limited, the inflow profile is balanced, the problem of excessive water outflow of the production layer is restrained, and the service life and recovery ratio of an oil well are improved.

When the flow rate of the formation fluid is small or the water content is relatively low, the flow rate is small and the viscosity of the fluid is large (the viscosity of oil is larger than that of water), so that the momentum of the formation fluid is small when the formation fluid enters the water control mechanism 16, and the momentum of the formation fluid entering the cyclone chamber 22 is small due to the existence of the viscosity in the inflow channel 20, so that the formation fluid cannot rotate at a high speed in the cyclone chamber 22, and further flows to the outflow opening 21 positioned at the center of the cyclone chamber 22 in a mode of approximately bending arc, a high-speed flowing state cannot be obtained, and the speed of the formation fluid in the state flowing out of the outflow opening 21 is small, so that large additional resistance cannot be generated, the oil yield of the production layer can be effectively ensured, and the liquid yield of each production layer can be balanced.

It should be noted that the oil and water extraction device 6 may be applied to a vertical well, or may be applied to a horizontal well, and preferably applied to a directional well. The upper and lower positional relationship described in the present application is a positional relationship with respect to a wellhead. The vertical direction in the vertical well is the vertical direction, and the vertical position relationship can be determined for the position relationship relative to the wellhead in the horizontal well.

In this embodiment, the upper and lower ends of the central tube 23 may be connected in series with the oil pipe 3, and the production fluid (formation fluid) for the production zone in the central tube 23 flows into and is transported to the surface. The axial direction of the center tube 23 is the length direction of the center tube 23. The outer tube 15 is fixedly sleeved outside the central tube 23, and a fluid channel communicated with the outside of the outer tube 15 is formed between the outer tube 15 and the central tube 23. The fluid channel can input stratum fluid, meanwhile, a water control mechanism 16 can be arranged between the outer tube 15 and the central tube 23, and the inlet 19 of the water control mechanism 16 is communicated with the fluid channel. In this manner, formation fluid may enter the inlet 19 of the water control mechanism 16 via the fluid passageway and, in turn, enter the interior of the water control mechanism 16.

In this embodiment, the outer tube 15 may be threaded outside the center tube 23 and provide protection to the various components within the outer tube 15. The threaded connection portion of the outer tube 15 and the central tube 23 is located below the water control mechanism 16. The connection between the outer tube 15 and the central tube 23 may have a sealing structure (such as a sealing ring) to prevent the fluid entering the fluid channel from leaking out of the water control mechanism 16.

Further, a screen jacket 12 is sleeved outside the central tube 23 above the outer tube 15; the lower end of the screen jacket 12 is connected with the upper end of the outer tube 15. The fluid passage between the outer tube 15 and the central tube 23 communicates with the outside through the screen jacket 12 for the input of formation fluids. The screen jacket 12 may filter the incoming formation fluid, thus providing sand control and protecting the device. The upper end of the outer tube 15 is provided with a butt joint 13 to connect with the lower end of the screen jacket 12 and to ensure that the fluid in the screen jacket 12 does not flow out.

Specifically, the screen jacket 12 includes, from outside to inside, a protective sleeve, a filter layer, a support net, a guide net, a wire-wound net, and a framework layer. The screen jacket 12 with the structure is wrapped outside the central pipe 23, and can play roles in sand prevention, flow guide and protection. In field application, the accuracy and the number of the filter screens can be adjusted according to the required sand blocking intensity, and the fluid entering the screen sleeve 12 is filtered by the filter layer and then guided by the guide layer to enter the water control mechanism 16.

As shown in fig. 4, the central tube 23 comprises a first base pipe 11 and a second base pipe 17 connected with the lower end of the first base pipe 11; the screen sleeve 12 is fixedly sleeved outside the first base pipe 11, and the outer pipe 15 is fixedly sleeved outside the second base pipe 17. The upper end of the first base pipe 11 is provided with a coupling 10 for connecting the oil pipe 3. As can be seen, the water control device 6 may comprise a screen portion 7 and a water control portion 14. The screen pipe part 7 and the water control part 14 are connected through the butt joint 13, and the screen pipe part 7 comprises a first base pipe 11, a screen sleeve 12, a coupling 10 and the butt joint 13; the water control portion 14 includes a second base pipe 17, an outer pipe 15, and a water control mechanism 16.

Considering that the flowing state of stratum fluid is complex after entering the reservoir and the screen sleeve 12, a plurality of rectangular rectifying grooves 24 are arranged on the outer wall of the central tube 23 for convenient regulation and control and smooth entering the inflow port 19 of the water control mechanism 16; the length direction of the rectangular rectifying groove 24 is parallel to the axial direction of the central pipe 23. The rectangular rectifying grooves 24 are uniformly arranged along the circumferential direction of the center pipe 23. One of the water control mechanisms 16 is provided in each of the rectangular rectifying grooves 24. Specifically, the water control mechanism 16 is located at a middle position of the width of the rectangular rectifying groove 24 in the circumferential direction.

Wherein, the flowing direction of the stratum fluid passing through the screen sleeve 12 is rectified to flow along the axial direction of the central pipe 23 under the guidance of the rectangular rectifying groove 24, so that the fluid state flowing into the water control mechanism 16 is ensured to be stable, and the inflow of the fluid is regulated. The groove walls between two adjacent rectangular rectifying grooves 24 can also support the inner wall of the outer pipe 15. It will be seen that the oil and water extraction control device 6 may be provided with a plurality of control mechanisms 16, preferably one control mechanism 16 per control device 6, and evenly distributed around the circumference of the central pipe 23, as determined by the nature of the formation at the level of application.

In the water control mechanism 16, the inlet 19 may be located on an end face of the water control mechanism 16 and at an end of the inflow channel 20. In this way, formation fluid may enter the inflow channel 20 by inertia after entering the inflow port 19, and may then quickly enter the swirling chamber 22 to form a swirling flow.

Specifically, to ensure the flow rate of the fluid entering the water control mechanism 16, the inlet 19 includes a first inlet 19a located at the upper end of the water control mechanism 16, and a second inlet 19b located at the lower end of the water control mechanism 16. The inflow passage 20 includes a first passage 21a that communicates the first inflow port 19a with the swirl chamber 22, and a second passage 21b that communicates the second inflow port 19b with the swirl chamber 22. Wherein the first inlet 19a is directed upward in the axial direction of the center tube 23, and the second inlet 19b is directed downward in the axial direction of the center tube 23. The water control mechanism 16 has a central symmetrical structure, so that the water control mechanism is more beneficial to processing and forming.

In this embodiment, the formation fluid enters the swirling chamber 22 through the inflow channel 20 to form a swirling flow, wherein the inflow channel 20 is a straight channel, and the inflow channel 20 may be led into the swirling chamber 22 along a tangential direction with respect to the swirling chamber 22. In this way, the fluid discharged from the inflow channel 20 enters the swirling chamber 22 through the outer edge of the swirling chamber 22, and moves rotationally at a high speed toward the outflow port 21 in the center of the swirling chamber 22, and forms a high restriction resistance at the outflow port 21.

In the present embodiment, the area of the inflow opening 19 is larger than the cross-sectional area of the inflow passage 20. By providing the inlet 19 and the inflow channel 20 in this configuration, an acceleration effect is created when the fluid flows through the inlet 19 to the inflow channel 20, so that the fluid is more likely to form a swirl in the swirl chamber 22, thereby providing a better restriction resistance. Specifically, the diameter of the inlet 19 is larger than the diameter of the inflow channel 20, and as shown in fig. 6 and 7, the inlet 19 and the inflow channel 20 form a funnel structure.

In the water control mechanism 16, the swirl chamber 22 has a disk structure as a whole, and the swirl chamber 22 is perpendicular to the radial direction of the center pipe 23. Specifically, the swirl chamber 22 is approximately disc-shaped. The cyclone chamber has higher flatness and smoothness. Further, the ratio of the diameter of the cyclone chamber 22 to the thickness thereof is 8-15: 1, a step of; the flatness of the inner wall of the swirl chamber 22 is less than + -0.001 mm and the surface roughness is less than 0.00016mm.

The central position of the cyclone chamber 22 is provided with the outlet 21 (penetrated by the central line), the cyclone chamber 22 can be in a flat cylindrical structure, or the side surface provided with the outlet 21 can be a conical surface, so that the depth (or thickness) of the cyclone chamber 22 gradually deepens from the outer edge to the center, and in particular, the degree of the conical surface can be less than 10 degrees. The outlet 21 is penetrated by the central line of the cyclone chamber 22 and is positioned at the central position of the side surface of the cyclone chamber 22, the diameter of the outlet 21 is selected to be 1mm-4mm, and the specification can be flexibly selected according to the condition of an oil field. The outlet 21 forms a nozzle structure, and for better throttling effect, the inner wall of the outlet 21 is a conical surface, and the taper of the conical surface is selected to be larger than 20 degrees. The conical surface of the outlet 21 gradually reduces the inner diameter of the outlet 21 along the fluid output direction, so that a better throttling resistance is formed for the fluid.

Considering that the general stratum fluid contains not only crude oil, but also water, the method can provide different resistance pressure drops under different flow rates and physical properties according to the controlled corresponding production horizon fluid flow rate and physical property changes (such as the content ratio of the crude oil and the water), and has wider applicability.

Based on the fact that the viscosity of crude oil in formation fluid is high and the inertia of water is high, the inflow channel 20 is arranged, so that the water control mechanism 16 can automatically adapt to physical properties and flow of fluid, different resistance pressure drops are provided according to specific fluid flow and physical properties, and the applicability is high. This allows the water control device 6 to have fluid identification, fluid diversion and fluid restriction effects, and the water control device 6 can autonomously regulate fluid flow based on pre-estimated formation fluid flow designs, depending on fluid composition and its properties.

In the present embodiment, the water control mechanism 16 has an outer contact surface and an inner contact surface facing each other (in the radial direction of the central tube 23). The outflow opening 21 is located on the inner mating surface. Wherein, the inner bonding surface is a plane to bond with the outer wall of the central tube 23, and the outer bonding surface is a circular arc surface to bond with the inner wall of the outer tube 15. In this embodiment, the water control mechanism 16 may be of a split construction, such as by a rectangular block and a cover having the circular arc surface being radially covered.

Specifically, in order to facilitate the installation of the water control mechanism 16, an accommodating groove for installing the water control mechanism 16 is formed on the outer wall of the central tube 23; the fluid through hole 18 is provided on the bottom wall of the receiving groove. The inner engagement surface engages the bottom wall of the receiving recess and the outlet 21 is in aligned communication with the fluid through bore 18; the inlet 19 is located outside the receiving tank. For better service life and avoiding fluid corrosion, the outer surface of the water control mechanism 16 (at least the surface contacting with the fluid) is made of metal with high erosion resistance.

In summary, the oil extraction water control device 6 is provided with the water control mechanism 16, so that different resistance pressure drops can be automatically generated according to the flow and physical property changes of the fluid at the production level to realize dynamic adjustment of the production pressure difference at the production level, and the oil extraction water control device has wider applicability. When the controlled production level produces oil, formation fluid flows through the screen sleeve 12 and the water control mechanism 16 and then enters the production channel (the inside of the central pipe 23 and the inside of the oil pipe 3), and when the flow rate of the controlled production level is increased or a large amount of water is produced, the water control device 6 can automatically increase the reverse pressure drop, increase the fluid resistance and play a role in controlling water. Meanwhile, the water control device 6 is simple in structure, low in manufacturing cost and wide in application value.

Referring to fig. 1, another embodiment of the present application further provides a schematic structure of a directional well completion string, where the directional well completion string includes: an oil pipe 3 which can be put into the casing 2; the upper end of the oil pipe 3 is provided with a hanging packer 1; the oil pipe 3 is provided with a plurality of isolation packers 5 below the suspension packer 1; the isolation packer 5 is used for sealing and separating an oil sleeve annulus between the sleeve 2 and the oil pipe 3; the oil extraction water control device 6 according to any one of the embodiments above; and one oil extraction and water control device 6 is connected in series on the oil pipe 3 between every two adjacent isolation packers 5.

Wherein, in order to facilitate the running of the directional well completion oil production string, the tail end of the directional well completion oil production string can be provided with a guide shoe 9. The hanging packer 1 may function to hang up the entire completion string. The isolation packer 5 isolates the lower casing 2 (pump string) from the production string (tubing 3) and separates the formation of multiple reservoir sections (production zones). The directional well oil production string can effectively solve the problems of high water content, low yield and low efficiency in the production process after the first completion of the directional well, the directional well oil production string is put into a shaft, water production of a water production layer section is inhibited by the directional well oil production string, oil production is improved, and finally the directional well oil production string is put into a pumping string completion production.

In this embodiment, the hanging packer 1 and the isolation packer 5 are both a desirable completion tool, so that the completion string can be taken out of the well at a later stage. It can be seen that the upper hanging packer 1 and the isolation packer 5 of the interval in the directional well completion string are deblocked so that the entire directional well completion string can be pulled out if necessary.

To facilitate setting of the directional well completion string, the directional well completion string may further comprise a setting string 4 that can be run into the tubing; the lower end of the setting pipe column 4 is in a blocking state.

As shown in fig. 2 and 3, a sealing cylinder 8 is connected to the upper end and the lower end of each isolation packer 5; the setting pipe column 4 is provided with two sealing rings 42 which are respectively matched with the sealing cylinder 8. The pipe wall of the setting pipe column 4 between the two sealing rings 42 is provided with a through hole; the sealing ring 42 is positioned in the sealing cylinder 8 to separate the sealing ring 42 from the sealing cylinder in an up-down sealing way, so that the isolation packer 5 is set by pressing the through hole into the setting tubular column 4. Wherein the sealing ring 42 is in interference fit with the sealing cylinder 8.

When the two sealing rings 42 of the setting string 4 are located in the sealing barrels 8 at the upper and lower ends of the isolation packer 5, respectively, the two sealing rings 42 form a setting space in the annulus between the setting string 4 and the center tube of the isolation packer 5, which is in communication with the through hole. By pressing into the setting string 4, the pressure sets the isolation packer 5 via the through hole and the setting space.

As shown in fig. 2, the setting pipe column 4 comprises a sealing rod provided with the sealing ring 42, and a plug connected with the lower end of the sealing rod; the sealing rod comprises an upper joint 41, a connecting rod 43 and a lower joint 4; the upper end of the connecting rod 43 is connected with the upper joint 41, and the lower end of the connecting rod 43 is connected with the lower joint 4. One of the two seal rings 42 is sleeved outside the upper joint 41 and above the connecting rod 43, and the other is sleeved outside the lower end of the connecting rod 43 and above the lower joint 4. The through hole is located on the connecting rod 43. Specifically, the seal ring 42 may be a vulcanized ring, and preferably, the seal ring 42 is a skeleton seal ring 42. In order to prevent back pressure, a one-way valve can be arranged on the through hole.

Wherein, a sealing rod (also called a flushing pipe) is placed inside the well completion pipe string, and is hung on the lower part of a setting pipe string 4 (a releasing pipe string) of the upper hanging packer 1, and mainly plays a role in setting an auxiliary isolation packer 5. After the isolation packer 5 is set, the washpipe is pulled out of the well with the upper casing string.

The embodiment of the application also provides a well completion method of the oil production string of the dead well of the directional well, which comprises the following steps: an oil pipe is put into the sleeve; the oil pipe is connected with the suspension packer 1, the isolation packer 5 and the oil extraction water control device; then, ball throwing and pressing are carried out in the oil pipe to set the hanging packer 1; then the setting pipe column 4 is put into the oil pipe; positioning two sealing rings 42 of the setting string 4 in a sealing cylinder 8 to which the upper and lower ends of the isolation packer 5 are connected; pressing into the setting tubular column 4 and transmitting pressure to the isolation packer 5 through the through hole to set the isolation packer 5; and (5) checking sealing. Further, a plurality of isolation packers 5 are sequentially set from bottom to top by the setting pipe string 4.

The construction operation process after the directional well runs out of the well oil production pipe column in place is as follows: firstly, ball throwing, pressing and setting are carried out in an oil pipe 3 to hang a packer 1, and a well completion string lifted and lowered is tested and hung. Then, the annular space between the casing 2 and the oil pipe 3 is pressurized to seal the suspended packer 1. And then the setting pipe column 4 (also called as a releasing pipe column) is put into the bottom of the well through the releasing tool, the setting pipe column 4 is lifted up, and after the vulcanized rings (sealing rings 42) on the pipe column of the setting pipe column 4 are lifted into the sealing cylinders 8 at the two ends of the isolation packer 5, the (lowest) isolation packer 5 is set by pressing into the oil pipe 3. Finally, seal inspection is carried out. Specifically, after the isolation packer 5 is set, a method of lowering the internal setting pipe column 4 of the oil pipe is adopted, a sealing rod is lowered to the lower part of the isolation packer 5, then the well is pressurized outwards into the oil pipe, and the setting condition of the isolation packer is judged by observing the annulus liquid return condition of a wellhead.

And lifting the setting pipe column 4 to the secondary isolation packer 5, setting the secondary isolation packer 5, and the like from bottom to top, sequentially setting the isolation packer 5 in the well completion pipe column, after all the isolation packers 5 are set, lifting the upper part sending pipe column together with the lower part setting auxiliary tool out of the well bore, and setting the well bore according to the later oil extraction and well repair requirements.

Any numerical value recited herein includes all values of the lower and upper values that increment by one unit from the lower value to the upper value, as long as there is a spacing of at least two units between any lower value and any higher value. For example, if it is stated that the number of components or the value of a process variable (e.g., temperature, pressure, time, etc.) is from 1 to 90, preferably from 20 to 80, more preferably from 30 to 70, then the purpose is to explicitly list such values as 15 to 85, 22 to 68, 43 to 51, 30 to 32, etc. in this specification as well. For values less than 1, one unit is suitably considered to be 0.0001, 0.001, 0.01, 0.1. These are merely examples that are intended to be explicitly recited in this description, and all possible combinations of values recited between the lowest value and the highest value are believed to be explicitly stated in the description in a similar manner.

Unless otherwise indicated, all ranges include endpoints and all numbers between endpoints. "about" or "approximately" as used with a range is applicable to both endpoints of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30," including at least the indicated endpoints.

All articles and references, including patent applications and publications, disclosed herein are incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not substantially affect the essential novel features of the combination. The use of the terms "comprises" or "comprising" to describe combinations of elements, components, or steps herein also contemplates embodiments consisting essentially of such elements, components, or steps. By using the term "may" herein, it is intended that any attribute described as "may" be included is optional.

Multiple elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step may be divided into separate plural elements, components, parts or steps. The disclosure of "a" or "an" to describe an element, component, section or step is not intended to exclude other elements, components, sections or steps.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated herein by reference for the purpose of completeness. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to forego such subject matter, nor should the inventors regard such subject matter as not be considered to be part of the disclosed subject matter.

Claims

1. A directional well completion production string, comprising:

oil extraction water control device; the oil pipe between every two adjacent isolation packers is connected with one oil extraction and water control device in series; the oil extraction water control device comprises: an outer tube; the central tube is sleeved in the outer tube; the wall of the central tube is provided with a fluid through hole which is communicated with the inside of the central tube; a water control mechanism installed between the outer tube and the center tube; the water control mechanism is provided with a rotational flow chamber, a water inlet, a water outlet and an inflow channel; the cross section of the cyclone chamber, which is vertical to the radial direction of the central pipe, is circular, and the central line of the cyclone chamber is parallel to the radial direction; the outflow port is communicated with the cyclone chamber and the fluid through hole; the outflow port is positioned on the central line of the cyclone chamber; the inflow channel communicates the inflow port with the cyclone chamber; the inflow channel is communicated into the cyclone cavity and enables fluid input into the cyclone cavity to form cyclone;

a setting string capable of being lowered into the tubing; the lower end of the setting pipe column is in a blocking state; the upper end and the lower end of each isolation packer are respectively connected with a sealing cylinder; the setting pipe column is provided with two sealing rings which are respectively matched with the sealing cylinder; the pipe wall of the setting pipe column positioned between the two sealing rings is provided with a through hole; when the two sealing rings of the setting pipe column are respectively positioned at the sealing cylinders at the upper end and the lower end of the isolation packer, the two sealing rings form a setting space in an annulus between the setting pipe column and a central pipe of the isolation packer, and the setting space is communicated with a through hole of the setting pipe column, so that pressure is caused to set the isolation packer through the through hole of the setting pipe column and the setting space by pressing the inside of the setting pipe column;

the setting pipe column comprises a sealing rod provided with the sealing ring and a plug connected with the lower end of the sealing rod; the sealing rod comprises an upper joint, a connecting rod and a lower joint; the upper end of the connecting rod is connected with the upper joint, and the lower end of the connecting rod is connected with the lower joint; one of the two sealing rings is sleeved outside the upper joint and above the connecting rod, and the other sealing ring is sleeved outside the lower end of the connecting rod and above the lower joint; and the through hole of the setting pipe column is positioned on the connecting rod.

2. The completion string of claim 1, wherein the hanging packer and the isolation packer are both removable completion tools.

3. The completion string of claim 1, wherein: the sealing ring is in interference fit with the sealing cylinder.

4. The completion string of claim 1, wherein: the sealing ring is a framework sealing ring.

5. The completion string of claim 1, wherein: and a one-way valve is arranged on the through hole of the setting pipe column.

6. The completion string of claim 1, wherein said inflow passage opens into said swirl chamber tangentially to said swirl chamber.

7. The completion string of claim 1, wherein the ratio of the diameter of the swirl chamber to the thickness thereof is 8-15: 1, a step of; the flatness of the inner wall of the cyclone chamber is lower than +/-0.001 mm, and the surface roughness is lower than 0.00016mm.

8. The completion string of claim 1, wherein a length of the inflow channel is parallel to an axial direction of a base pipe of the oil and water control device.

9. The completion string of any of claims 1-8, wherein said inlet comprises a first inlet at an upper end of said water control mechanism and a second inlet at a lower end of said water control mechanism;

10. The completion string of claim 9, wherein the first inlet is directed upward and the second inlet is directed downward.

11. The completion string of claim 10, wherein the side surface of the swirl chamber where the outlet is formed is a conical surface having a taper of less than 10 degrees; the inner wall of the outflow port is a conical surface, and the taper of the conical surface is larger than 20 degrees.

12. The completion string of claim 1, wherein the inlet has an area greater than a cross-sectional area of the inflow passage.

13. The completion string of claim 1, wherein: the water control mechanism is provided with an outer bonding surface and an inner bonding surface which are opposite to each other; the outflow port is positioned on the inner bonding surface; the outer joint surface is an arc surface and is jointed with the inner wall of the outer tube.

14. The completion string of claim 13, wherein: the outer wall of the central tube of the oil extraction water control device is provided with a containing groove for installing the water control mechanism; the fluid through hole is arranged on the bottom wall of the accommodating groove; the inner fitting surface is fitted with the bottom wall of the accommodating groove, and the outflow port is communicated with the fluid through hole in an aligned manner; the inflow port is positioned outside the accommodating groove.

15. The completion string of claim 1, wherein: the outer wall of the central pipe of the oil extraction water control device is provided with a plurality of rectangular rectifying grooves which are uniformly distributed along the circumferential direction; the length direction of the rectangular rectifying groove is parallel to the axial direction of the central tube; and each rectangular rectifying groove is internally provided with one water control mechanism.

16. The completion string of claim 1, wherein: a screen sleeve is sleeved outside the central pipe of the oil extraction water control device above the outer pipe; the lower end of the screen sleeve is connected with the upper end of the outer tube.

17. The completion string of claim 16, wherein: the screen sleeve comprises a protective sleeve, a filter layer, a supporting net, a guide net, a winding net and a framework layer from outside to inside.

18. A method of completing a well using a directional well completion string as defined in any one of claims 1-17, comprising:

lowering the setting pipe column into the oil pipe;

pressing the inside of the setting pipe column, transmitting pressure to the isolation packer through the through hole of the setting pipe column, and setting the isolation packer;

and (5) checking sealing.

19. The method of completing a well of claim 18, wherein: and sequentially setting a plurality of isolation packers from bottom to top through the setting pipe column.