Anchoring packer for multilateral well and multilateral well drilling equipment

Abstract

The invention provides an anchoring packer for a multilateral well and multilateral well drilling equipment. The anchoring packer comprises a mandrel assembly, an anchoring mechanism and a rubber sleeve sealing mechanism. The mandrel assembly comprises an upper connector with a pressure transmission hole and a mandrel forming a first pressure cavity with the upper connector. The anchoring mechanism comprises an upper slip arranged on the mandrel in a sleeving mode, a conical sleeve and a first piston assembly, the conical sleeve is in sliding connection with the upper slip through an inclined face, and the conical sleeve and the mandrel are limited through a first shear pin. The rubber sleeve sealing mechanism is arranged below the anchoring mechanism and comprises a second piston assembly, a rubber sleeve and an extrusion sleeve, and the overlapping position of the second piston assembly and the first piston assembly is connected through a second shear pin. The mandrel is provided with a hydraulic channel communicated with the first pressure cavity and the second pressure cavity. During operation, hydraulic oil enters through the pressure transmission hole to drive the first piston assembly to move upwards to cut off the first shear pin, and the conical sleeve is pushed to enable the upper slip to anchor the well wall in the radial direction; meanwhile, the second piston assembly is driven to move downwards to cut off the second shear pin, and the rubber sleeve is extruded to radially expand to achieve sealing.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas production equipment, in particular to an anchor packer for a branch well and branch well drilling equipment. Background Art

[0002] With the rapid development of the offshore oil industry, the operational timeliness and operating costs of oilfield development and production are becoming increasingly critical issues. Window sidetracking technology can effectively increase oil and gas production and significantly reduce economic costs, whether for old or new wells. Anchoring devices play an extremely important role in branch well window sidetracking operations. Traditional anchors only have an anchoring function and cannot prevent rock cuttings from falling into the main well during sidetracking. They are only suitable for situations where the main wellbore is abandoned. Furthermore, traditional anchors without isolation functions may cause leakage, well kicks, or even blowouts during sidetracking due to the connection between the old wellbore and the formation. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an anchored packer for a branch well and branch well drilling equipment. These devices aim to address the problem that the anchoring devices in the related art lack a sealing function, resulting in rock cuttings falling into the main well during drilling, causing blockage of the main well, or leakage, kicks, or blowouts caused by communication between the main well and the formation during drilling.

[0004] The present invention provides an anchor packer for a branch well, comprising: A spindle assembly includes an upper joint, a spindle, and a guide shoe, wherein the upper joint and the guide shoe are detachably connected to the top and bottom ends of the spindle, respectively. A pressure transmission hole is provided on the upper joint, and a first pressure chamber is provided between the upper joint and the outer top position of the spindle; Anchoring mechanism, the anchoring mechanism includes an upper slip, a tapered sleeve and a first piston assembly sleeved on the outside of the spindle, the upper slip and the tapered sleeve are sequentially arranged between the upper joint and the first piston assembly, the outer top end of the tapered sleeve is provided with a first guide inclined surface extending upward and toward the spindle, the inner bottom end of the upper slip is provided with a second guide inclined surface extending downward and away from the spindle, the first guide inclined surface is fitted and slidably connected with the second guide inclined surface, the first piston assembly is used to push the tapered sleeve to move upward, and a first shear pin is provided between the tapered sleeve and the spindle; a rubber cylinder sealing mechanism, the rubber cylinder sealing mechanism being arranged below the anchoring mechanism, the rubber cylinder sealing mechanism comprising a second piston assembly, a rubber cylinder sleeve, and an extrusion sleeve which are sequentially sleeved on the outer side of the mandrel from top to bottom, the second piston assembly being used to squeeze the rubber cylinder sleeve downward so as to expand the rubber cylinder sleeve along the radial direction of the mandrel, the second piston assembly partially overlapping the first piston assembly, and a second shear pin being provided on the overlapping portion; The first shear pin and the second shear pin both extend radially along the core shaft. A second pressure chamber is formed between the first piston assembly, the second piston assembly and the core shaft. A hydraulic channel connecting the first pressure chamber and the second pressure chamber is provided on the core shaft. The oil pressure in the second pressure chamber is used to provide an upward thrust for the first piston assembly and a downward thrust for the second piston assembly.

[0005] The anchoring seal for branch wells provided according to the present invention also includes a lower cava, which is arranged between the conical sleeve and the first piston assembly, and the outer bottom end of the conical sleeve is provided with a third guide slope extending downward and toward the direction of the core axis, and the inner top end of the lower cava is provided with a fourth guide slope extending upward and away from the core axis. The third guide slope is fitted and slidably connected with the fourth guide slope, and a third shear pin is provided between the lower cava and the conical sleeve, and the third shear pin extends radially along the core axis. The shear force that the third shear pin can withstand is greater than the shear force that the first shear pin and the second shear pin can withstand.

[0006] According to the anchoring packer for branch wells provided by the present invention, the first piston assembly includes a first piston sleeve, a first push cylinder and a shear ring, the top end of the first push cylinder is connected to the bottom end of the lower slip, the top end of the first piston sleeve is connected to the bottom end of the first push cylinder, the bottom end of the first piston sleeve is connected to the shear ring, the shear ring is arranged on the outside of the second piston assembly, and the second shear pin is arranged between the shear ring and the second piston assembly.

[0007] According to the anchor packer for branch wells provided by the present invention, the second piston assembly includes a second piston sleeve and a second push cylinder, the bottom end of the second push cylinder is connected to the top end of the rubber sleeve, and the bottom end of the second piston sleeve is connected to the top end of the second push cylinder.

[0008] According to the anchoring packer for branch wells provided by the present invention, the top end of the second piston sleeve is located between the inner side of the bottom end of the first piston sleeve and the outer side of the core shaft, and the second pressure chamber is formed between the inner side wall of the first piston sleeve, the top surface of the second piston sleeve and the outer side wall of the core shaft.

[0009] According to the anchoring packer for branch wells provided by the present invention, a locking ring is provided between the first push cylinder and the core shaft, and between the second push cylinder and the core shaft, and a mutually cooperating anti-retraction structure is provided between the outer side of the locking ring and the inner side of the corresponding first push cylinder or the inner side of the second push cylinder.

[0010] According to the anchor packer for a branch well provided by the present invention, the rubber sleeves include at least three, and the three rubber sleeves are distributed along the axial direction of the core shaft.

[0011] The present invention also provides a branch well drilling equipment, comprising the above-mentioned anchor packer for the branch well.

[0012] The present invention has the following advantages due to the adoption of the above technical solution: The anchoring packer for branch wells provided by the present invention includes a mandrel assembly, an anchoring mechanism and a rubber sleeve sealing mechanism. The mandrel assembly includes a mandrel, an upper joint and a guide shoe. The upper joint and the guide shoe are detachably connected to the top and bottom ends of the mandrel respectively. A first pressure chamber is provided between the upper joint and the outer top position of the mandrel. The upper joint is provided with a pressure transmission hole connecting the inside and outside of the first pressure chamber. The anchoring mechanism includes an upper slip, a conical sleeve and a first piston assembly sleeved on the outer side of the mandrel. The upper slip and the conical sleeve are sequentially provided between the upper joint and the first piston assembly. The outer top end of the conical sleeve is provided with a first guide bevel extending upward and toward the mandrel. The inner bottom end of the upper slip is provided with a second guide bevel extending downward and away from the mandrel. The first guide bevel and the second guide bevel are fitted and slidably connected. The first piston assembly is used to push the conical sleeve to move upward. A first shear pin is provided between the conical sleeve and the mandrel. The rubber cylinder sealing mechanism is disposed below the anchoring mechanism and includes a second piston assembly, a rubber cylinder sleeve, and an extrusion sleeve, which are sequentially sleeved on the outer side of the mandrel from top to bottom. The second piston assembly is used to downwardly compress the rubber cylinder sleeve to cause the rubber cylinder sleeve to expand radially along the mandrel. The second piston assembly partially overlaps with the first piston assembly, and a second shear pin is provided in the overlapping portion. The first shear pin and the second shear pin both extend radially along the mandrel. A second pressure chamber is formed between the first and second piston assemblies and the mandrel. A hydraulic channel is provided on the mandrel connecting the first and second pressure chambers. The oil pressure in the second chamber is used to provide upward thrust for the first piston assembly and downward thrust for the second piston assembly. During field operations, the upper joint, connected to the whipstock, is lowered into the wellbore. Pressure is applied through the pressure-transmitting hole on the upper joint, and hydraulic oil flows through the first pressure chamber and the hydraulic channel into the second pressure chamber, providing an upward thrust for the first piston assembly and a downward thrust for the second piston assembly. During the gradual pressurization process, the first shear pin between the upper slip and the tapered sleeve, as well as the second shear pin between the second piston assembly and the first piston assembly, are sheared. The first piston assembly drives the tapered sleeve upward, which in turn drives the upper slip to move radially along the mandrel, pushing the upper slip into the wellbore wall and thus suspending the tool in the wellbore. Simultaneously, the second piston assembly descends, squeezing the rubber sleeve together with the extrusion sleeve, causing the rubber sleeve to expand radially along the mandrel and sealing the rubber sleeve against the wellbore wall, achieving isolation. The anchoring seal for branch wells provided by the present invention has the reliable anchoring ability of traditional anchoring devices, can ensure that the tool is stably suspended on the well wall, and has a reliable load-bearing function. At the same time, the rubber sleeve also has certain anti-blowout and anti-leakage functions, which can effectively prevent rock cuttings dropped during side drilling from falling into the main well, avoiding pollution to the main well.

[0013] Furthermore, in the branch well drilling equipment provided by the present invention, since the anchor packer for branch wells as described above is provided, it has the same advantages as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0015] Figure 1 It is a cross-sectional view of an anchor packer for a branch well provided by one embodiment of the present invention.

[0016] Reference numerals: 1: Upper joint; 2: Mandrel; 3: Guide shoe; 4: Fixing pin; 5: Pressure transmission hole; 6: First pressure chamber; 7: Upper slip; 8: Conical sleeve; 9: First shear pin; 10: Rubber sleeve; 11: Extrusion sleeve; 12: Second shear pin; 13: Hydraulic channel; 14: Lower slip; 15: Third shear pin; 16: First piston sleeve; 17: First push cylinder; 18: Shear ring; 19: Second piston sleeve; 20: Second push cylinder; 21: Second pressure chamber; 22: Locking ring. DETAILED DESCRIPTION

[0017] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0018] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means more than two, unless otherwise specifically defined.

[0020] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0021] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0022] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0023] The present invention provides an anchored packer for a branch well, comprising a mandrel assembly, an anchoring mechanism, and a rubber sleeve sealing mechanism. The mandrel assembly includes a mandrel, an upper joint with a pressure transmission hole, and a guide shoe. A first pressure chamber is formed between the upper joint and the mandrel. The anchoring mechanism comprises an upper slip, a tapered sleeve, and a first piston assembly. The tapered sleeve has a first guide bevel, and the upper slip has a second guide bevel, which slide in contact with each other. The first piston assembly is used to push the tapered sleeve upward, and the tapered sleeve is connected to the mandrel via a first shear pin. The rubber sleeve sealing mechanism is located below the anchoring mechanism and comprises a second piston assembly, a rubber sleeve, and an extrusion sleeve. The downward pressure of the second piston assembly causes the rubber sleeve to expand radially. The second piston assembly partially overlaps the first piston assembly and is connected by a second shear pin. A second pressure chamber is formed between the first and second piston assemblies and the mandrel. Hydraulic oil enters the second pressure chamber through the pressure transmission hole, the first pressure chamber, and the hydraulic passage, simultaneously providing upward thrust to the first piston assembly and downward thrust to the second piston assembly. After pressurization, the first and second shear pins shear off. The first piston assembly pushes the tapered sleeve upward, which, through its inclined surface, drives the upper slips radially to anchor the wellbore. Simultaneously, the second piston assembly descends, collaborating with the extrusion sleeve to compress the rubber sleeve radially, expanding and setting the seal against the wellbore. This tool provides reliable anchoring and load-bearing capacity, and the rubber sleeve provides blowout and loss prevention, preventing sidetracking cuttings from entering the main wellbore and causing contamination.

[0024] The following combination Figure 1 The anchored packer for a branch well of the present invention is described.

[0025] An embodiment of the present invention provides an anchor packer for a branch well, comprising a mandrel assembly, an anchoring mechanism, and a rubber sleeve sealing mechanism.

[0026] The spindle assembly includes an upper joint 1, a spindle 2 and a guide shoe 3. The inner bottom end of the upper joint 1 is provided with an internal thread, and the outer top end of the spindle 2 is provided with an external thread. The upper joint 1 and the spindle 2 are connected by threads, and a fixing pin 4 is provided at the position where the upper joint 1 and the spindle 2 are connected. The fixing pin 4 extends along the radial direction of the spindle 2 to prevent the upper joint 1 from being buckled after being connected to the spindle 2.

[0027] A sealing groove is further provided on the inner side surface of the connection position between the upper joint 1 and the core shaft 2 , and a sealing ring is installed in the sealing groove to ensure the sealing between the upper joint 1 and the core shaft 2 .

[0028] A pressure transmission hole 5 is provided on the upper joint 1 , and the pressure transmission hole 5 is used to be connected to a hydraulic oil pipeline. A first pressure chamber 6 is provided between the upper joint 1 and the spindle 2 .

[0029] The anchoring mechanism includes multiple upper slips 7, a tapered sleeve 8, and a first piston assembly. The bottom end of the upper joint 1 is provided with first limiting grooves evenly distributed along the circumference of the upper joint 1. The multiple upper slips 7 are evenly distributed along the circumference of the mandrel 2 on the outside of the mandrel 2, and the multiple upper slips 7 are arranged one-to-one with the multiple first limiting grooves. The multiple first limiting grooves are used to install and limit the circumferential position of the upper slips 7.

[0030] The outer side of the top of the conical sleeve 8 is provided with a plurality of second limiting grooves, and the bottom ends of the plurality of upper slips 7 are arranged in the plurality of second limiting grooves in a one-to-one correspondence. The bottom surface of the second limiting groove is provided with a first guiding slope, which extends upward and toward the direction of the mandrel 2. The inner bottom of the upper slip 7 is provided with a second guiding slope, which extends downward and away from the mandrel 2. When the upper slip 7 is connected to the second limiting groove of the conical sleeve 8, the first guiding slope and the second guiding slope are in contact and sliding connection.

[0031] The top end of the first piston assembly is connected to the bottom end of the tapered sleeve 8. When the first piston assembly moves upward, the first piston assembly drives the tapered sleeve 8 to move upward, and the bottom end of the upper joint 1 limits the upward movement of the upper slip 7. Under the action of the first guide slope and the second guide slope, the upper slip 7 moves along the radial direction of the core shaft 2 away from the core shaft 2, thereby driving the outer side surface of the upper slip 7 to bite into the well wall.

[0032] A first shear pin hole is provided on the tapered sleeve 8 and radially penetrates the tapered sleeve 8. A first shear pin groove is provided on the central shaft 2 at a position corresponding to the initial position of the first pin hole. The first shear pin 9 passes through the first shear pin hole and enters the first shear pin groove to limit the initial position of the tapered sleeve 8 and limit the axial movement of the tapered sleeve 8 along the central shaft 2.

[0033] The rubber cylinder sealing mechanism is arranged below the anchoring mechanism, and the rubber cylinder sealing mechanism comprises a second piston assembly, a rubber cylinder sleeve 10 and an extrusion sleeve 11 which are sequentially sleeved on the outer side of the spindle 2 from top to bottom.

[0034] A fixing pin 4 inserted in the radial direction of the core shaft 2 is provided between the extrusion sleeve 11 and the core shaft 2 . The fixing pin 4 is used to limit the axial movement and circumferential rotation of the extrusion sleeve 11 along the core shaft 2 .

[0035] The bottom end of the first piston assembly and the top end of the second piston assembly have a partially overlapping portion, and the overlapping portion is nested. A second shear pin hole is provided in the overlapping portion, and the second shear pin 12 is passed through the second shear pin hole to limit the initial relative position of the first piston assembly and the second piston assembly.

[0036] A second pressure chamber 21 is provided between the first piston assembly, the second piston assembly and the spindle 2 , and a hydraulic channel 13 communicating with the first pressure chamber 6 and the second pressure chamber 21 is provided on the spindle 2 .

[0037] During field operations, the upper joint 1 is connected to the whipstock and sent downhole. The hydraulic oil is pressurized through the pressure transmission hole 5 on the upper joint 1. The hydraulic oil enters the second pressure chamber 21 through the first pressure chamber 6 and the hydraulic channel 13, thereby providing an upward thrust for the first piston assembly and a downward thrust for the second piston assembly. When the thrust exerted on the first and second piston assemblies reaches the maximum shear force that the first shear pins 9 and the second shear pins 12 can withstand, the first shear pins 9 and the second shear pins 12 are sheared. At this time, the first piston assembly drives the conical sleeve 8 upward, and the conical sleeve 8 drives the upper slip 7 to move radially along the core shaft 2, pushing the upper slip 7 to bite into the well wall, thereby suspending the tool in the well. At the same time, the second piston assembly descends and squeezes the rubber sleeve 10 together with the extrusion sleeve 11, causing the rubber sleeve 10 to expand radially along the core shaft 2, sealing the rubber sleeve on the well wall, and achieving the sealing effect. The anchoring seal for branch wells provided by the present invention has the reliable anchoring ability of traditional anchoring devices, can ensure that the tool is stably suspended on the well wall, and has a reliable load-bearing function. At the same time, the rubber sleeve 10 also has certain anti-blowout and anti-leakage functions, which can effectively prevent the rock cuttings dropped during the side drilling process from falling into the main well, avoiding pollution to the main well.

[0038] In some embodiments, lower slips 14 are further included, and the number of lower slips 14 can be the same as that of upper slips 7. A plurality of third limiting grooves are provided on the outer bottom of the conical sleeve 8, and the tops of the plurality of lower slips 14 are disposed in the plurality of third limiting grooves in a one-to-one correspondence. A third guide slope is provided at the bottom of the third limiting groove, extending downward and toward the spindle 2. A fourth guide slope is provided on the inner top of the lower slips 14. When the lower slips 14 enter the third limiting groove, the third guide slope engages and slides with the fourth guide slope.

[0039] A plurality of fourth limiting grooves are provided at the top end of the first piston assembly, and the fourth limiting grooves are provided in one-to-one correspondence with the plurality of lower cavas 14 , and the bottoms of the plurality of lower cavas 14 are provided in one-to-one correspondence in the plurality of fourth limiting grooves, and the fourth limiting grooves are used to install and limit the circumferential position of the lower cavas 14 .

[0040] A third shear pin hole is provided on the lower cava 14 and passes through the lower cava 14 in the radial direction of the central shaft 2. A third shear pin groove is provided at a position of the conical sleeve 8 corresponding to the initial position of the third shear pin hole. The third shear pin 15 passes through the third shear pin hole and enters the third shear pin groove to limit the initial position of the lower cava 14.

[0041] It should be noted that in order to make the upper cava 7 open before the lower cava 14, the shear force that the third shear pin 15 can withstand needs to be greater than the shear force that the first shear pin 9 and the second shear pin 12 can withstand. In this way, when the first piston assembly moves upward, the first shear pin 9 will break before the third shear pin 15. After the conical sleeve 8 opens the upper cava 7, as the thrust continues to increase, the third shear pin 15 breaks, and at this time the lower cava 14 is opened.

[0042] In some embodiments, the first piston assembly includes a first piston sleeve 16 and a first push cylinder 17. The fourth limiting groove is provided on the outer top of the first push cylinder 17, that is, the first push cylinder 17 is connected to the lower slip 14 via the fourth limiting groove. The top of the first piston sleeve 16 is threadedly connected to the bottom of the first push cylinder 17.

[0043] In some embodiments, the second piston assembly includes a second piston sleeve 19 and a second push cylinder 20 , the bottom end of the second push cylinder 20 is connected to the shoulder guard at the top of the rubber sleeve 10 , and the top end of the second push cylinder 20 is threadedly connected to the bottom end of the second piston sleeve 19 .

[0044] An annulus is provided between the bottom end of the first piston sleeve 16 and the spindle 2. The top end of the second piston sleeve 19 is located within the annulus. A shear ring 18 is also connected to the bottom end of the first piston sleeve 16, and the shear ring 18 is sleeved on the outside of the second piston sleeve 19. The inner and outer walls of the second piston sleeve 19 are respectively provided with sealing grooves, and sealing rings are provided in the sealing grooves for sealing and sliding connection with the spindle 2 and the inner side wall of the first piston sleeve 16. The inner side wall of the first piston sleeve 16 is also provided with a sealing groove, and a sealing ring is provided in the sealing groove for sealing and sliding connection with the spindle 2. A second pressure chamber 21 is formed by the top end face of the second piston sleeve 19, the top end face of the annulus of the first piston sleeve 16, the inner side surface of the first piston sleeve 16, and the outer side surface of the spindle 2.

[0045] The second shear pin hole is set on the shear ring 18, and the second shear pin groove is set at a position corresponding to the initial position of the second piston sleeve 19 and the second shear pin hole. The second shear pin 12 passes through the second shear pin hole and enters the second shear pin groove of the second piston sleeve 19 to limit the initial relative position of the first piston sleeve 16 and the second piston sleeve 19.

[0046] In some embodiments, a locking ring 22 is provided on the outer side of the spindle 2 at a position corresponding to the first push cylinder 17 and at a position corresponding to the second push cylinder 20. A fixing pin 4 is provided between the first push cylinder 17 and the second push cylinder 20 and the locking ring 22, and the top of the fixing pin 4 does not extend beyond the outer side of the locking ring 22 to prevent the fixing pin 4 from obstructing the movement of the first push cylinder 17 or the second push cylinder 20. After the fixing pin 4 is installed, it can prevent the locking ring 22 from rotating circumferentially and limit the axial movement of the locking ring 22.

[0047] A cooperating stop structure is provided on the outer side of the lock ring 22 and the inner side of the corresponding first push cylinder 17 or second push cylinder 20. The stop structure is used to prevent the first push cylinder 17 from retracting downward and to prevent the second push cylinder 20 from retracting upward. For example, the stop structure can be a horseshoe buckle.

[0048] In some embodiments, at least three rubber sleeves 10 may be provided, and the plurality of rubber sleeves 10 are connected in series on the outside of the core shaft 2 along the axial direction of the core shaft 2 . The more rubber sleeves 10 there are, the better the sealing effect is.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An anchor packer for a branch well, characterized in that: include: A spindle assembly comprises an upper joint (1), a spindle (2) and a guide shoe (3), wherein the upper joint (1) and the guide shoe (3) are detachably connected to the top and bottom ends of the spindle (2), respectively; a pressure transmission hole (5) is provided on the upper joint (1), and a first pressure chamber (6) is provided between the upper joint (1) and the outer top of the spindle (2); An anchoring mechanism, the anchoring mechanism comprises an upper cava (7), a conical sleeve (8) and a first piston assembly sleeved on the outside of the spindle (2), the upper cava (7) and the conical sleeve (8) being sequentially arranged between the upper joint (1) and the first piston assembly, the outer top end of the conical sleeve (8) being provided with a first guide inclined surface extending upward and toward the spindle (2), the inner bottom end of the upper cava (7) being provided with a second guide inclined surface extending downward and away from the spindle (2), the first guide inclined surface being fitted and slidably connected with the second guide inclined surface, the first piston assembly being used to push the conical sleeve (8) to move upward, and a first shear pin (9) being provided between the conical sleeve (8) and the spindle (2); A rubber cylinder sealing mechanism, the rubber cylinder sealing mechanism is arranged below the anchoring mechanism, the rubber cylinder sealing mechanism comprises a second piston assembly, a rubber cylinder sleeve (10) and an extrusion sleeve (11) which are sequentially sleeved on the outer side of the core shaft (2) from top to bottom, the second piston assembly is used to squeeze the rubber cylinder sleeve (10) downward so that the rubber cylinder sleeve (10) expands along the radial direction of the core shaft (2), the second piston assembly partially overlaps with the first piston assembly, and a second shear pin (12) is provided on the overlapping portion; The first shear pin (9) and the second shear pin (12) both extend radially along the spindle (2); a second pressure chamber (21) is formed between the first piston assembly, the second piston assembly and the spindle (2); a hydraulic channel (13) connecting the first pressure chamber (6) and the second pressure chamber (21) is provided on the spindle (2); the oil pressure in the second pressure chamber (21) is used to provide an upward thrust for the first piston assembly and a downward thrust for the second piston assembly.

2. The anchor packer for branch wells according to claim 1, characterized in that: The invention also includes a lower cava (14), which is arranged between the conical sleeve (8) and the first piston assembly, and the outer bottom end of the conical sleeve (8) is provided with a third guide inclined surface extending downward and toward the center shaft (2), and the inner top end of the lower cava (14) is provided with a fourth guide inclined surface extending upward and away from the center shaft (2), and the third guide inclined surface is slidably connected with the fourth guide inclined surface. A third shear pin (15) is provided between the lower cava (14) and the conical sleeve (8), and the third shear pin (15) extends radially along the center shaft (2). The shear force that the third shear pin (15) can withstand is greater than the shear force that the first shear pin (9) and the second shear pin (12) can withstand.

3. The anchor packer for branch wells according to claim 2, characterized in that: The first piston assembly includes a first piston sleeve (16), a first push cylinder (17) and a shear ring (18), the top end of the first push cylinder (17) is connected to the bottom end of the lower slip (14), the top end of the first piston sleeve (16) is connected to the bottom end of the first push cylinder (17), the bottom end of the first piston sleeve (16) is connected to the shear ring (18), the shear ring (18) is sleeved on the outside of the second piston assembly, and the second shear pin (12) is arranged between the shear ring (18) and the second piston assembly.

4. The anchor packer for branch wells according to claim 3, characterized in that: The second piston assembly comprises a second piston sleeve (19) and a second push cylinder (20), wherein the bottom end of the second push cylinder (20) is connected to the top end of the rubber sleeve (10), and the bottom end of the second piston sleeve (19) is connected to the top end of the second push cylinder (20).

5. The anchor packer for branch wells according to claim 4, characterized in that: The top end of the second piston sleeve (19) is located between the inner side of the bottom end of the first piston sleeve (16) and the outer side of the core shaft (2), and the second pressure chamber (21) is formed between the inner side wall of the first piston sleeve (16), the top surface of the second piston sleeve (19) and the outer side wall of the core shaft (2).

6. The anchor packer for branch wells according to claim 4, characterized in that: A locking ring (22) is provided between the first push cylinder (17) and the spindle (2), and between the second push cylinder (20) and the spindle (2). A mutually cooperating stop structure is provided between the outer side of the locking ring (22) and the inner side of the corresponding first push cylinder (17) or the inner side of the second push cylinder (20).

7. The anchor packer for a branch well according to claim 1, characterized in that: The rubber sleeves (10) include at least three, and the three rubber sleeves (10) are distributed along the axial direction of the core shaft (2).

8. A branch well drilling equipment, characterized in that: It comprises the anchor packer for branch wells according to any one of claims 1 to 7.

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