A horizontal well open hole segmented jump fracturing combination tool and method

Abstract

The present application discloses a horizontal well open hole segmented jump fracturing combination tool and method, which relates to the field of horizontal well fracturing technology. Not only is the tool structure reasonable, the on-site operation is convenient, and the operation cycle is short, but it can also effectively utilize the disturbance stress between the cracks, increase the crack transformation volume, and increase the reservoir transformation effect. The fracturing tool includes multiple groups of jump fracturing components, pressure-driven sleeves, pressure-holding ball seats, check valves, and rotary guide shoes; the jump fracturing components include jump fracturing tools and the first horizontal section pipe external packer; the jump fracturing tool includes an inner center pipe component, a front-stage sleeve component, a rear-stage sleeve component, an outer center pipe component, a rubber tube component, a fracturing fluid pipe, and an annular cavity; when the front-stage sleeve component is opened, the inner center pipe component connects the wellbore and the wellbore annulus through the fracturing fluid pipe; when the rear-stage sleeve component is opened, the inner center pipe component connects the wellbore and the wellbore annulus through the annular cavity. The present application also discloses a horizontal well open hole segmented jump fracturing method.

Description

Technical Field

[0001] The present application relates to the technical field of horizontal well fracturing, and in particular to a horizontal well open hole segmented jump fracturing combination tool and method. Background Art

[0002] At present, staged fracturing of horizontal wells is still the main means of increasing oil and gas production. Conventional staged fracturing of horizontal wells uses a certain fracturing process to sequentially fracture from the toe end to the heel end of the horizontal well, and after fracturing, a transverse hydraulic fracture perpendicular to the wellbore is formed. The disadvantages of conventional staged fracturing are: the fracture spacing is large, the fractures formed after fracturing are simple, there is less mutual interference between fractures, and the fracturing effect on some reservoirs, especially tight reservoirs, is limited. In order to solve the above technical problems, staged volume fracturing of horizontal wells came into being. Studies have shown that staged volume fracturing of horizontal wells has a good effect on increasing the production of reservoirs (especially low permeability reservoirs), and the technical key of volume fracturing is to change the stress field around the horizontal well through the interference between fractures and increase the probability of fracture network formation. Therefore, in order to use fracture interference to form a fracture network after fracturing, researchers proposed the infinite fracturing process and the single-stage multi-cluster fracturing process based on shortening the fracture spacing. In sequential fracturing, the interference area of ​​hydraulic fractures increases with the increase in the number of fractures, but the minimum fracture spacing cannot be less than the stress disturbance radius, otherwise it is not conducive to the formation of lateral fractures that are beneficial to production increase.

[0003] Skip fracturing is a fracturing process that changes the sequence of traditional fracturing. A third hydraulic fracture is established between two hydraulic fractures formed by fracturing with the help of a special process. Since the stress field between the two hydraulic fractures formed by the first fracturing has changed, the third fracture effectively extends under the changed stress field to form a transverse fracture that is beneficial to production increase. Moreover, the optimal fracture spacing during skip fracturing is smaller than the optimal spacing of traditional sequential fracturing, and it can maximize the interference between fractures and optimize the fracture extension trajectory, which is beneficial to increase the reservoir transformation volume and achieve the maximum production increase effect. However, due to the limitations of tools and process methods, this skip fracturing that changes the fracturing sequence and makes full use of the disturbance stress to increase the probability of fracture network formation has never been realized. Summary of the invention

[0004] The embodiments of the present application provide a horizontal well open hole segmented jump fracturing combination tool and method, which not only has a reasonable tool structure, convenient on-site operation, and a short operation cycle, but also can effectively utilize the disturbance stress between fractures, increase the fracture transformation volume, and enhance the reservoir transformation effect.

[0005] To achieve the above-mentioned purpose, on the one hand, an embodiment of the present application provides a horizontal well open hole segmented jump fracturing combination tool, comprising a plurality of jump fracturing assemblies, pressure-driven sleeves, pressure-holding ball seats, check valves and rotary guide shoes, which are located in a horizontal well and are sequentially connected in series along the axial direction; the jump fracturing assembly comprises a jump fracturing tool and a first horizontal section pipe external packer connected to the lower end of the jump fracturing tool; the first horizontal section pipe external packer is used to segment the wellbore; the jump fracturing tool comprises an inner center pipe assembly; a front-stage sleeve assembly and a rear-stage sleeve assembly are sequentially arranged in the inner center pipe assembly along the axial direction, and the front-stage sleeve assembly is close to the pressure-driven sleeve assembly. A movable sleeve is set; an outer center pipe assembly is arranged outside the inner center pipe assembly; an annular cavity is formed between the inner center pipe assembly and the outer center pipe assembly; a fracturing fluid pipe is also arranged between the inner center pipe assembly and the outer center pipe assembly; a rubber sleeve assembly is arranged at the lower part of the outer center pipe assembly; the rubber sleeve assembly is located in the middle position of two preset jump-type fracturing sections; the outlet of the annular cavity and the outlet of the fracturing fluid pipe are respectively located on both sides of the rubber sleeve assembly; when the front-stage sleeve assembly is opened, the inner cavity of the inner center pipe assembly is connected to the wellbore and the wellbore annulus through the fracturing fluid pipe; when the rear-stage sleeve assembly is opened, the inner cavity of the inner center pipe assembly is connected to the wellbore and the wellbore annulus through the annular cavity.

[0006] Furthermore, the inner center tube assembly includes a first inner center tube, a second inner center tube and a third inner center tube connected in series in axial direction; the upper end of the first inner center tube is connected to an upper coupling; the lower end of the third inner center tube is connected to a lower joint through a lower coupling; the rear-stage sliding sleeve assembly and the front-stage sliding sleeve assembly are both arranged in the second inner center tube, and the front-stage sliding sleeve assembly is arranged close to the pressure-driven sliding sleeve; the outer center tube assembly includes a pressure cap, an outer center tube and a rubber tube; the outer center tube is located on the outer side of the second inner center tube; the pressure cap is arranged at the mouth of the outer center tube; the rubber tube is connected between the outer side of the lower end of the second inner center tube and the outer side of the upper end of the lower coupling; the first inner center tube, the outer center tube and the pressure cap jointly form a first annular cavity; the second inner center tube, the rubber tube, the first inner center tube and the lower coupling jointly form a second annular cavity; the fracturing fluid tube is arranged between the second inner center tube and the outer center tube.

[0007] Furthermore, a first through hole is provided on the upper end side wall of the second inner center tube; the front-stage sleeve assembly includes a front-stage sleeve and a front-stage ball seat arranged in the front-stage sleeve; both ends of the front-stage sleeve are sealed and connected in the second inner center tube; after the front-stage sleeve is opened, the hole of the front-stage sleeve is connected with the first through hole; the rear-stage sleeve assembly includes a rear-stage sleeve and a rear-stage ball seat arranged in the rear-stage sleeve; both ends of the rear-stage sleeve are sealed and connected in the second inner center tube; after the rear-stage sleeve is opened, the hole of the rear-stage sleeve is connected with the fracturing fluid pipe; the diameter of the front-stage ball seat is smaller than the diameter of the rear-stage ball seat.

[0008] Furthermore, a second through hole and a third through hole are respectively provided on the side walls at both ends of the rubber tube; the rubber tube assembly is located between the second through hole and the third through hole; the second through hole connects the first annular cavity and the second annular cavity; the third through hole connects the second annular cavity and the annular space between the wellbore and the well wall.

[0009] Furthermore, the rubber cylinder assembly comprises two compressed rubber cylinders; rubber cylinder seats are provided at the ends of the two compressed rubber cylinders; and a spacer ring is provided between the two compressed rubber cylinders.

[0010] Furthermore, the horizontal well open hole segmented jump fracturing combination tool also includes a first horizontal section hydraulic centralizer arranged at the lower end of the first horizontal section external pipe packer.

[0011] Furthermore, a second horizontal section external pipe packer and a second horizontal section hydraulic centralizer are also provided at the upper end of the jump-type fracturing tool close to the wellhead.

[0012] On the other hand, an embodiment of the present application further provides a process method based on the above-mentioned horizontal well open hole staged jump fracturing combination tool, comprising the following steps:

[0013] Lowering the horizontal well open hole segmented skipping fracturing combination tool to a preset position;

[0014] Put in the pressure-holding ball and inject the reservoir protection fluid, so that the jump fracturing tool and the first horizontal section external pipe packer are both set, and the first horizontal section hydraulic centralizer is straightened;

[0015] Inject fracturing fluid into the wellhead, and the pressure drives the sliding sleeve to open to form a fracturing channel, and start fracturing in the first fracturing stage;

[0016] After the first fracturing stage is completed, jump fracturing begins:

[0017] The first soluble fracturing ball is put in and the pressure is continued. The first soluble fracturing ball falls on the front sleeve assembly of the jump fracturing tool between the first fracturing stage and the second fracturing stage. As the pressure increases, the front sleeve assembly opens, and the fracturing fluid enters the fracturing layer of the third fracturing stage through the inner cavity of the inner center pipe assembly, the holes of the front sleeve assembly and the fracturing fluid pipe in sequence, and the fracturing of the third fracturing stage begins.

[0018] After the fracturing of the third fracturing stage is completed, a second soluble fracturing ball is put in, and the fracturing continues. The second soluble fracturing ball falls on the rear-stage sliding sleeve assembly of the jump-type fracturing tool between the first fracturing stage and the second fracturing stage. As the pressure increases, the rear-stage sliding sleeve assembly opens, and the fracturing fluid enters the fracturing layer of the second fracturing stage through the inner cavity of the inner center pipe assembly, the holes and the annular cavity of the rear-stage sliding sleeve assembly in sequence, and the fracturing of the second fracturing stage begins; the diameter of the second soluble fracturing ball is greater than the diameter of the first soluble fracturing ball, and the second fracturing stage is located between the first fracturing stage and the third fracturing stage;

[0019] The skip fracturing process is repeated until all fracturing stages are completed.

[0020] Compared with the prior art, this application has the following beneficial effects:

[0021] The horizontal well segmented jump fracturing tool containing inner and outer double-layer pipes used in the embodiment of the present application controls the upper and lower fracturing channels in the horizontal well through the fracturing ball, and uses the annular space and the ball-throwing sleeve to change the injection order of the fracturing fluid during the fracturing process, forming a horizontal well jump fracturing process. After the first stage of fracturing, a soluble fracturing ball is put in. When the fracturing ball falls into the front-stage ball seat located at the third stage of the horizontal well, the front-stage sleeve opens, and the fracturing fluid enters the first compression layer through the front-stage sleeve; after the third stage of fracturing is completed, the second fracturing ball is put in, and the fracturing ball falls into the rear-stage ball seat. The pressure drives the lower ball seat to slide down, and the rear-stage fracturing fluid inlet opens. The fracturing fluid enters the second stage of the horizontal well along the annular space of the inner and outer center pipes, establishes a fracturing channel, and then changes the fracturing order of the second and third stages, forming a jump fracturing process of the second and third stages. The jump fracturing tool and the matching fracturing tool combination are installed in sequence according to the number of staged fracturing of the horizontal well, and the corresponding fracturing balls are used to complete the multi-stage jump fracturing. The skip fracturing procedure is simple and the operation cycle is short. The additional stress field generated by the skip fracturing is used to increase the probability of volume fracture network formation and achieve the purpose of increasing production. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 This is a schematic diagram of the structure of a horizontal well open hole segmented jump fracturing assembly tool according to an embodiment of the present application;

[0024] Figure 2 This is a schematic diagram of the structure of a skip-type fracturing tool in an embodiment of the present application;

[0025] Figure 3 This is a schematic diagram of the structure of the first external packer in the embodiment of the present application;

[0026] Figure 4 This is a schematic diagram of the structure of the hydraulic centralizer in the embodiment of the present application;

[0027] Figure 5 This is a schematic diagram of the structure of the pressure-driven sleeve in the embodiment of the present application;

[0028] Figure 6 This is a schematic diagram of the structure of the pressure-holding ball seat in the embodiment of the present application;

[0029] Figure 7 This is a schematic diagram of the structure of a check valve in an embodiment of the present application;

[0030] Figure 8 It is a schematic diagram of the structure of the rotary guide shoe in the embodiment of the present application. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply 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 a limitation on the present application.

[0033] In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0034] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0035] Reference Figure 1 The embodiment of the present application provides a horizontal well open hole segmented jump fracturing combination tool, a second horizontal section external pipe packer 6, a second horizontal section hydraulic straightener 7, multiple groups of jump fracturing components 1, a pressure-driven sliding sleeve 2, a pressure-holding ball seat 3, a check valve 4 and a rotary guide shoe 5. It should be noted that the number of jump fracturing components 1 can be selected according to the number of segments designed for horizontal well fracturing. The following is an example of three groups of jump fracturing components 1, and the tools are connected by casing.

[0036] The second horizontal section external pipe packer 6, the second horizontal section hydraulic centralizer 7, three sets of jump-type fracturing components 1, the pressure-driven sliding sleeve 2, the pressure-holding ball seat 3, the check valve 4 and the rotary guide shoe 5 are all located in the horizontal section of the wellbore and are connected in series in sequence along the axial direction.

[0037] The skip-type fracturing assembly 1 comprises a skip-type fracturing tool 101 and a first horizontal section external pipe packer 102 and a first horizontal section hydraulic centralizer 103 which are sequentially connected to the lower end of the skip-type fracturing tool 101 .

[0038] The second horizontal section external packer 6 and the first horizontal section external packer 102 can separate the wellbore into large fracturing sections, and the skip fracturing tool 101 can separate each large fracturing section into two skip fracturing sections. Figure 1 The second and third sections in the well are two skip-type fracturing sections. Similarly, the fourth and fifth sections are also two skip-type fracturing sections, and the sixth and seventh sections are also two skip-type fracturing sections. At the same time, the first section near the bottom of the well is the first large fracturing section, the second and third sections form the second large fracturing section, the fourth and fifth sections form the third large fracturing section, and the sixth and seventh sections form the fourth large fracturing section.

[0039] During fracturing, except for the first section, each large fracturing section is fractured in a skip-type manner between the skip-type fracturing sections. For example, in the second large fracturing section, the third section near the wellhead is first fractured, and then the second section between the third section and the first section is fractured, forming a skip-type fracturing. However, each large fracturing section is fractured in sequence from the bottom of the well to the wellhead. For example, after the first large section is fractured, the second large section, the third large section, and the fourth large section are then fractured.

[0040] Reference Figure 2 The jump-type fracturing tool 101 includes an inner center pipe assembly, an outer center pipe assembly, a front-stage sliding sleeve assembly, a rear-stage sliding sleeve assembly and a rubber cartridge assembly.

[0041] The inner center pipe assembly includes a first inner center pipe 112, a second inner center pipe 113 and a third inner center pipe 114 which are connected in series in the axial direction. The upper end of the first inner center pipe 112 is connected to the upper coupling 111. The upper end of the third inner center pipe 114 is connected to the second center pipe 113 through the lower coupling 136, and the lower end of the third inner center pipe 114 is connected to other pipe strings through the lower joint 137. The rear stage sliding sleeve assembly and the front stage sliding sleeve assembly are both arranged in the second inner center pipe 113, and the front stage sliding sleeve assembly is arranged close to the pressure drive sliding sleeve 2.

[0042] The outer center pipe assembly includes a pressure cap 115, an outer center pipe 116 and a rubber tube 117. The outer center pipe 116 is located outside the second inner center pipe 113. The pressure cap 115 is arranged at the mouth of the outer center pipe 116. The rubber tube 117 is connected between the lower end of the second inner center pipe 113 and the upper end of the lower coupling. The second inner center pipe 113, the outer center pipe 116 and the pressure cap 115 together form a first annular cavity 118. The second inner center pipe 113, the rubber tube 117 and the lower coupling 115 together form a second annular cavity 120. A fracturing fluid pipe 119 is arranged between the second inner center pipe 113 and the outer center pipe 116.

[0043] The front-stage sliding sleeve assembly includes a front-stage sliding sleeve 121 and a front-stage ball seat 122 arranged in the front-stage sliding sleeve 121. The front-stage sliding sleeve is composed of the second inner center tube 113 and the front-stage sliding sleeve 123, and the front-stage sliding sleeve 123 is fixed in the second inner center tube 113 by the second shear pin 124. The front-stage ball seat 122 is connected to the front-stage sliding sleeve 123 by a thread. When the soluble ball of corresponding size falls into the front-stage ball seat 122, the liquid channel in the tube is blocked, the pressure in the tube increases, and when the internal and external pressure difference increases to the shear pressure set by the second shear pin 124, the shear pin is cut off, the ball seat moves down, the front-stage sliding sleeve 123 falls, and the second inner center tube 113 is connected with the fracturing fluid pipe 119 welded on the second inner center tube 113 and the outer center tube 116 to form a fracturing fluid channel.

[0044] A first through hole 125 is provided on the upper side wall of the second inner center tube 113. The rear stage sliding sleeve assembly includes a rear stage sliding sleeve 126 and a rear stage ball seat 127 arranged in the rear stage sliding sleeve 126. The rear stage sliding sleeve is composed of the second inner center tube 113 and the rear stage sliding sleeve 128, and the rear stage sliding sleeve 126 is fixed in the second inner center tube 113 by the first shear pin 129. The rear stage ball seat 127 is connected to the rear stage sliding sleeve 128 by a thread. When the soluble ball of corresponding size falls into the rear stage ball seat 127, the liquid channel in the tube is blocked, the pressure in the tube increases, and when the internal and external pressure difference increases to the shear pressure set by the first shear pin 129, the shear pin is cut off, the ball seat moves down, the rear stage sliding sleeve 128 falls, and the inner tube of the rear stage sliding sleeve is connected with the first through hole 125, and is connected with the first annular cavity 118 and the rear stage fracturing fluid outlet 130, and a new section of fracturing channel is formed from the fracturing fluid outlet. The diameter of the front ball seat 122 is smaller than the diameter of the rear ball seat 127 .

[0045] The lower part of the rubber tube tube 117 is sleeved with a rubber tube assembly, which includes two compression rubber tubes 131 and two rubber tube seats 132. A spacer ring 133 is arranged between the two compression rubber tubes, and the rubber tube seat 132 is located at the outer end of the compression rubber tube 131.

[0046] A second through hole 134 and a third through hole 135 are respectively provided on the side walls at both ends of the rubber tube 117. The rubber tube assembly is located between the second through hole 134 and the third through hole 135, and the second through hole 134 communicates with the first annular cavity 118 and the second annular cavity 120. The third through hole 135 communicates with the second annular cavity 120 and the subsequent fracturing fluid outlet 130, and the subsequent fracturing fluid outlet 130 communicates with the wellbore and the well wall annulus.

[0047] The rubber cartridge assembly is located in the middle of the two preset jump fracturing sections. The outlet of the second annular cavity 120 and the outlet of the fracturing fluid pipe 119 are located on both sides of the rubber cartridge assembly, corresponding to the two fracturing layer sections.

[0048] The front-stage sliding sleeve 121 and the rear-stage sliding sleeve 126 are opened by soluble fracturing balls of different diameters. When the front-stage sliding sleeve 121 is opened, the inner cavity of the inner central pipe assembly is connected to the wellbore and the well wall annulus through the fracturing fluid pipe 119. The rear-stage ball seat 126 is a switch for controlling the jump layer fracturing. When the rear-stage sliding sleeve 126 is opened, the inner cavity of the inner central pipe assembly is connected to the wellbore and the well wall annulus through the first through hole 125, the first annular cavity 118 and the second annular cavity 120. After the fracturing fluid passes through the first through hole 125, the first annular cavity 118 and the second annular cavity 120, it flows out from the rear-stage fracturing fluid outlet 135 and enters the fracturing layer, forming a fracturing fluid injection channel to achieve cross-section jump layer fracturing.

[0049] Reference Figure 3The first horizontal section external pipe packer 102 includes a casing coupling 102-01, a packer center pipe 102-02, a packer fixing nail 102-03, a packer hydraulic cylinder 102-04, a packer piston 102-05, a packer stop seat 102-06, a packer rubber tube spacer ring 102-07, a packer rubber tube 102-08, a packer shear pin 102-09, and a packer lower joint 102-10.

[0050] The casing coupling 102-01 of the first horizontal section external packer 102 is connected to the packer center pipe 102-02 through casing threads. The packer fixing nail 102-03 is fixed to the left end of the packer cylinder 102-04 to prevent the cylinder from being detached from the packer center pipe 102-02. The packer cylinder 102-04, the packer piston 102-05, the packer stop seat 102-06, the packer rubber cylinder spacer ring 102-07 and the packer rubber cylinder 102-08 are respectively sleeved on the packer center pipe 102-02. The packer shear pin 102-09 fixes the cylinder and the piston. The packer lower joint 102-10 is the lower thread of the center pipe 102-02, which is used to connect the lower tool or pipe string.

[0051] The first horizontal section external packer 102 is located at the dividing point between the designed large sections to block the annular passage to prevent fracturing fluid from penetrating the layers. The first horizontal section external packer 102 is expanded and sealed by inserting a pressure-holding ball to increase the pressure in the wellbore before fracturing. After expansion and sealing, the locking thread is set to lock the packer to prevent the packer from being unsealed.

[0052] Reference Figure 4 The first horizontal section hydraulic centralizer 103 adopts a composite cyclone hydraulic centralizer. Specifically, the hydraulic centralizer 103 includes a centralizer coupling 103-01, a centralizer center tube 103-02, a centralizer roller rotating centralizing part 103-03, a centralizer centralizing sleeve 103-04, a centralizer hydraulic cylinder 103-05, a centralizer pressure transmission hole 103-06, a centralizer piston 103-07, a centralizer stop ring 103-08, a centralizer hydraulic variable diameter centralizing part 103-09, a centralizer limit seat 103-10, a centralizer conical ring 103-11, and a centralizer lower joint 103-12.

[0053] The two ends of the centralizer coupling 103-01 are respectively connected to the upper casing and the central tube 103-02 of the centralizer by threads. The centralizer roller rotating centralizing part 103-03 is sleeved on the central tube 103-02 of the centralizer, and the lower end of the centralizer roller rotating centralizing part 103-03 is connected to the centralizer centralizing sleeve 103-04. The lower end of the centralizer centralizing sleeve 103-04 is provided with a centralizer pressure transmission hole 103-06, a centralizer hydraulic cylinder 103-05 and a centralizer piston 103-07. The lower end of the centralizer piston 103-07 is connected to the centralizer hydraulic variable diameter centralizing part 103-09, and the lower end of the centralizer hydraulic variable diameter centralizing part 103-09 is fixed on the central tube 103-02 of the centralizer by a fixing nail. At the same time, the lower end of the centralizer hydraulic variable diameter centralizing part 103-09 is also provided with a centralizer limit seat 103-10. The lower end of the centralizer limit seat 103-10 is connected to the centralizer conical ring 103-11, and the centralizer conical ring 103-11 is connected to the centralizer lower joint 103-12.

[0054] The composite cyclone hydraulic centralizer can reduce the friction resistance of the casing during the casing running process and protect other parts of the hydraulic variable diameter centralizer. The centralizer strip of the hydraulic variable diameter part is squeezed and deformed by the pressure in the casing, which can achieve full diameter support of the wellbore and support the casing and completion tools in the center of the wellbore.

[0055] Reference Figure 5 The pressure driven sleeve 2 includes a sleeve coupling 201, a sleeve casing short section 202, a sleeve joint 203, a sleeve fixing pin 204, a sleeve shear pin 205, a pressure differential sleeve 206, a sleeve outer tube 207 and a sleeve lower joint 208.

[0056] The sleeve coupling 201 of the pressure driven sleeve 2 is connected to the sleeve casing nipple 202 by a casing thread. The sleeve casing nipple 202 is connected to the sleeve joint 203 by a thread. The sleeve joint 203 is connected to the sleeve outer tube 207 by a thread. The sleeve fixing pin 204 is fixed to the sleeve joint 203 and the sleeve outer tube 207. The sleeve shear pin 205 is fixed to the pressure difference sleeve 206 and the sleeve outer tube 207. The sleeve lower joint 208 is connected to the lower pipe string or tool.

[0057] The pressure driven sleeve 2 corresponds to the first fracturing stage of the horizontal well. When the pressure difference between the inside and outside of the wellbore reaches the design limit of the pressure driven sleeve 2, the sleeve shear pin 205 is sheared off, the pressure difference sleeve 206 slides down, the fracturing fluid outlet is opened, and a fracturing channel is formed.

[0058] Reference Figure 6The pressure-holding ball seat 3 includes a ball seat coupling 301, a pressure-holding ball 302, a ball seat 303 and a lower joint 304. The pressure-holding ball seat 3 is a channel for controlling the communication between the wellbore and the wellbore annulus. By inserting the pressure-holding ball 302 to close the circulation channel between the inside and outside of the pipe, the pressure inside the pipe rises. When the pressure value inside the pipe reaches the expansion and sealing design pressure value of all the packers, the packers outside the pipe are expanded and sealed.

[0059] Reference Figure 7 The check valve 4 includes a check valve coupling 401, a check valve main pipe 402, a check valve fluid valve 403 and a check valve lower joint 404. The check valve 4 is a pressure differential controlled one-way flow valve for liquid. When the pressure inside the pipe is greater than the pressure outside the pipe, the valve opens. On the contrary, when the pressure inside the pipe is less than the pressure outside the pipe, the flow valve closes.

[0060] Specifically, the check valve coupling 401 and the check valve main pipe 402 are threadedly connected to the casing, the check valve fluid valve 403 is fixed on the check valve main pipe 402, and the check valve lower joint 404 is connected to the lower pipe column.

[0061] Reference Figure 8 The rotary guide shoe 5 includes a rotary guide shoe upper joint 501, a rotary bearing 502, a rotating body 504, a fluid guide pipe 503 and a reaming blade 505. The upper end of the upper joint 501 has an internal thread, which is used to connect with the casing. The lower end of the upper joint 501 is connected to the rotating body 504 through the rotary bearing 502. The reaming blade 505 is arranged outside the rotating body 504. The rotary guide shoe 5 is connected to the lowermost end of the completion string. If the string encounters resistance during the well entry process, the pump is turned on for circulation. When the flowing liquid passes through the fluid guide pipe 503, the flowing liquid changes direction, generating a liquid flow force on the guide pipe wall, driving the rotating body 504 to rotate, so that the reaming blade 505 cuts the well wall, playing a reaming role.

[0062] The first horizontal section external pipe packer 6 and the second horizontal section external pipe packer 102 in the jump fracturing assembly 1 have the same structure and function, and the first horizontal section hydraulic centralizer 7 and the second horizontal section hydraulic centralizer 103 have the same structure and function, which will not be described in detail here.

[0063] Reference Figure 1 The working principle of the horizontal open hole segmented jump fracturing combination tool of the embodiment of the present application is as follows:

[0064] Each tool is connected in sequence through the casing. After all the tools are connected in sequence, they are guided into the well with a rotating guide shoe. During the lowering, reservoir protection liquid is injected. The reservoir protection liquid flows out from the rotating guide shoe through a one-way valve, which can clean the wellbore and reduce the friction of the tool string when it is lowered into the well.

[0065] After all tools are sent to the predetermined position, the pressure-holding ball 302 is put into the wellbore. After the pressure-holding ball 302 falls into the ball seat 303, the circulation channel between the wellbore and the well wall is closed, and the liquid is continuously pumped. The pressure in the wellbore increases. When the pressure reaches the packer expansion pressure, all the packers are expanded and sealed.

[0066] When starting staged fracturing, inject fracturing fluid into the wellbore. When the pressure reaches the design pressure of the pressure-driven sleeve 2, the pressure-driven sleeve 2 opens and starts fracturing the first section. After the first section of fracturing construction is completed, a fracturing ball is put in. Since the diameter of the fracturing ball is larger than the inner diameter of the ball seat assembly, the fracturing ball sits on the ball seat assembly. As the fracturing fluid is continuously injected into the inner tube, the pressure rises. When the pressure reaches the design pressure of the sleeve shear pin, the front-stage sleeve 121 opens, and the fracturing fluid enters the annulus from the hole of the front-stage sleeve 121, and the third section of the horizontal well is opened. Then the next fracturing ball is put in to open the inlet of the subsequent fracturing fluid. The fracturing fluid enters the second section of the horizontal well along the annulus, forming a skip-type fracturing process for the second and third sections. Subsequent fracturing is carried out in sequence according to the design steps to form a skip-type hydraulic fracture and promote the formation of complex fractures. After the fracturing construction is completed, the fracturing ball made of soluble material is dissolved, and finally the layer is closed and the fluid is discharged. It should be noted that when a horizontal well is fractured in stages, the corresponding fracturing order for the first section, the second section, the third section, the fourth section, the fifth section, the sixth section, the seventh section... is ①, ③, ②, ⑤, ④, ⑦, ⑥...

[0067] On the other hand, an embodiment of the present application further provides a process method based on the above-mentioned horizontal well open hole staged jump fracturing combination tool, comprising the following steps:

[0068] S1. Lower the horizontal well open hole segmented jump fracturing combination tool to the preset position:

[0069] All completion tools are connected in sequence according to the design requirements and lowered into the predetermined position in the well under the guidance of the rotating guide shoe 5.

[0070] S2, expansion seal external packer (including first horizontal section external packer 102, second horizontal section external packer 6) and hydraulic centralizer (first horizontal section hydraulic centralizer 103, second horizontal section hydraulic centralizer 7):

[0071] The pressure-holding ball 302 is put in and the reservoir protection fluid is injected, the pressure is held at 25 MPa, and the pressure is maintained for 2 minutes, so that the first horizontal section external pipe packers 102 are all set and the first horizontal section hydraulic centralizers 103 are all centralized.

[0072] S3. After cementing is completed, install the fracturing wellhead and prepare for fracturing.

[0073] S4, injecting fracturing fluid into the wellhead, the pressure drives the sliding sleeve 5 to open, forming a fracturing channel, and starting the first fracturing stage fracturing.

[0074] S5. After the first fracturing stage is completed, jump fracturing begins:

[0075] The first soluble fracturing ball is put in and the pressure is continued. The first soluble fracturing ball falls on the front sleeve 121 of the jump fracturing tool 101 between the first fracturing stage and the second fracturing stage. As the pressure increases, the front sleeve 121 opens, and the fracturing fluid enters the fracturing layer of the third fracturing stage through the inner cavity of the inner center pipe assembly, the holes of the front sleeve 121 and the fracturing fluid pipe in sequence, and the fracturing of the third fracturing stage begins (fracturing sequence ②);

[0076] After the fracturing of the third fracturing stage is completed, the second soluble fracturing ball is put in and the pressure is continued. The second soluble fracturing ball falls on the rear ball seat 124 of the jump fracturing tool 101 between the first fracturing stage and the second fracturing stage, and the fluid is continued to be injected into the wellbore. The pressure in the pipe increases due to the sealing effect of the fracturing ball. The high pressure drives the shear pin of the rear ball seat 124 to be sheared off, and the rear ball seat 124 slides down. The fracturing fluid enters the fracturing layer of the second fracturing stage through the inner cavity of the inner center pipe assembly, the holes and the annular cavity of the rear sleeve 123 assembly in turn, and the fracturing of the second fracturing stage begins (fracturing sequence ③).

[0077] S6. Repeat the skip fracturing process until all fracturing stages are completed:

[0078] After completing the second stage of fracturing, the upper and lower layers of the second and third stages are exchanged in the fracturing sequence, forming a skip fracturing. According to the fracturing procedures of the second and third stages, the fourth, fifth, sixth, seventh, etc. fracturing are completed in sequence, and the corresponding fracturing sequence is ⑤, ④, ⑦, ⑥, etc.

[0079] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A horizontal well open hole segmented jump fracturing combination tool, characterized in that: It includes multiple groups of jump-type fracturing components, pressure-driven sliding sleeves, pressure-holding ball seats, check valves and rotary guide shoes, which are located in a horizontal well and are connected in series in the axial direction; The jump-type fracturing assembly comprises a jump-type fracturing tool and a first horizontal section external pipe packer connected to the lower end of the jump-type fracturing tool; The first horizontal section external packer is used to segment the wellbore; The jump-type fracturing tool comprises an inner central tube assembly; a front-stage sliding sleeve assembly and a rear-stage sliding sleeve assembly are sequentially arranged in the inner central tube assembly along the axial direction, and the front-stage sliding sleeve assembly is arranged close to the pressure-driven sliding sleeve; an outer central tube assembly is arranged outside the inner central tube assembly; an annular cavity is formed between the inner central tube assembly and the outer central tube assembly; a fracturing fluid pipe is also arranged between the inner central tube assembly and the outer central tube assembly; A rubber cartridge assembly is sleeved on the lower part of the outer center tube assembly; the rubber cartridge assembly is located in the middle of two preset jump-type fracturing sections; the outlet of the annular cavity and the outlet of the fracturing fluid pipe are respectively located on both sides of the rubber cartridge assembly; When the front-stage sliding sleeve assembly is opened, the inner cavity of the inner center pipe assembly is connected to the wellbore and the well wall annulus through the fracturing fluid pipe; When the rear-stage sliding sleeve assembly is opened, the inner cavity of the inner center pipe assembly is connected to the wellbore and the well wall annulus through the annular cavity.

2. The horizontal well open hole segmented jump fracturing combination tool according to claim 1, characterized in that: The inner center tube assembly comprises a first inner center tube, a second inner center tube and a third inner center tube which are connected in series in the axial direction; the upper end of the first inner center tube is connected to an upper coupling; the lower end of the third inner center tube is connected to a lower joint through a lower coupling; The rear-stage sliding sleeve assembly and the front-stage sliding sleeve assembly are both arranged in the second inner center tube, and the front-stage sliding sleeve assembly is arranged close to the pressure-driven sliding sleeve; The outer center tube assembly comprises a pressure cap, an outer center tube and a rubber tube; the outer center tube is located outside the second inner center tube; the pressure cap is arranged at the mouth of the outer center tube; The rubber tube is connected between the lower end exterior of the second inner center tube and the upper end exterior of the lower coupling; The first inner center tube, the outer center tube and the pressure cap together form a first annular cavity; the second inner center tube, the rubber tube, the first inner center tube and the lower coupling together form a second annular cavity; The fracturing fluid pipe is arranged between the second inner central pipe and the outer central pipe.

3. The horizontal well open hole segmented jump fracturing combination tool according to claim 2, characterized in that: A first through hole is provided on the upper end side wall of the second inner central tube; the front-stage sliding sleeve assembly comprises a front-stage sliding sleeve and a front-stage ball seat arranged in the front-stage sliding sleeve; both ends of the front-stage sliding sleeve are sealed and connected in the second inner central tube; after the front-stage sliding sleeve is opened, the hole of the front-stage sliding sleeve is connected with the first through hole; The rear-stage sliding sleeve assembly includes a rear-stage sliding sleeve and a rear-stage ball seat arranged in the rear-stage sliding sleeve; both ends of the rear-stage sliding sleeve are sealed and connected in the second inner center pipe; after the rear-stage sliding sleeve is opened, the hole of the rear-stage sliding sleeve is connected with the fracturing fluid pipe; The diameter of the front ball seat is smaller than the diameter of the rear ball seat.

4. The horizontal well open hole segmented jump fracturing combination tool according to claim 2, characterized in that: The side walls at both ends of the rubber tube are respectively provided with a second through hole and a third through hole; the rubber tube assembly is located between the second through hole and the third through hole; the second through hole connects the first annular cavity and the second annular cavity; the third through hole connects the second annular cavity and the wellbore and the well wall annulus.

5. The horizontal well open hole segmented jump fracturing combination tool according to claim 1, characterized in that: The rubber cylinder assembly comprises two compressed rubber cylinders; rubber cylinder seats are arranged at the ends of the two compressed rubber cylinders; and a spacer ring is arranged between the two compressed rubber cylinders.

6. The horizontal well open hole segmented jump fracturing combination tool according to claim 1, characterized in that: The first horizontal section hydraulic centralizer is also provided at the lower end of the first horizontal section external pipe packer.

7. The horizontal well open hole segmented jump fracturing combination tool according to claim 1, characterized in that: The upper end of the jump-type fracturing tool close to the wellhead is also provided with a second horizontal section external pipe packer and a second horizontal section hydraulic centralizer.

8. A process method based on the horizontal well open hole segmented jump fracturing combination tool according to any one of claims 1 to 7, characterized in that: The following steps are involved: Lowering the horizontal well open hole segmented skipping fracturing combination tool to a preset position; Put in the pressure-holding ball and inject the reservoir protection fluid, so that the jump fracturing tool and the first horizontal section external pipe packer are both set, and the first horizontal section hydraulic centralizer is straightened; Inject fracturing fluid into the wellhead, and the pressure drives the sliding sleeve to open to form a fracturing channel, and start fracturing in the first fracturing stage; After the first fracturing stage is completed, jump fracturing begins: The first soluble fracturing ball is put in and the pressure is continued. The first soluble fracturing ball falls on the front sleeve assembly of the jump fracturing tool between the first fracturing stage and the second fracturing stage. As the pressure increases, the front sleeve assembly opens, and the fracturing fluid enters the fracturing layer of the third fracturing stage through the inner cavity of the inner center pipe assembly, the holes of the front sleeve assembly and the fracturing fluid pipe in sequence, and the fracturing of the third fracturing stage begins. After the fracturing of the third fracturing stage is completed, a second soluble fracturing ball is put in, and the fracturing continues. The second soluble fracturing ball falls on the rear-stage sliding sleeve assembly of the jump-type fracturing tool between the first fracturing stage and the second fracturing stage. As the pressure increases, the rear-stage sliding sleeve assembly opens, and the fracturing fluid enters the fracturing layer of the second fracturing stage through the inner cavity of the inner center pipe assembly, the holes and the annular cavity of the rear-stage sliding sleeve assembly in sequence, and the fracturing of the second fracturing stage begins; the diameter of the second soluble fracturing ball is greater than the diameter of the first soluble fracturing ball, and the second fracturing stage is located between the first fracturing stage and the third fracturing stage; The skip fracturing process is repeated until all fracturing stages are completed.

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