Device and method for cutting and mixing casing in horizontal wellbore

Abstract

The present invention provides a casing cutting and mixing filling device in a horizontal wellbore, comprising a cutting mechanism and a mixing mechanism, wherein the cutting mechanism comprises a rotating body and an injection port, the rotating body is provided with an installation groove along its axial direction, the injection port is provided on the rotating body along the circumference of the rotating body, the installation groove is communicated with the injection port, the cutting fluid can enter the installation groove to drive the rotating body to rotate and be ejected through the injection port; the mixing mechanism comprises a shell, the shell is rotatably connected to one end of the rotating body away from the installation groove, a grouting hole is provided at one end of the shell close to the injection port, the grouting hole is communicated with the injection port, and an outlet is provided at the other end of the shell.

Description

Technical Field

[0001] The invention belongs to the technical field of filling mining, and specifically relates to a device and method for cutting and mixing casing in a horizontal wellbore. Background Art

[0002] In mining projects, roof horizontal wells are mainly used for the exploitation of oil and gas resources such as shale gas and coalbed methane. With the high-intensity exploitation of coal resources, large-scale goafs are accompanied, which leads to surface subsidence, aquifer destruction, soil erosion, and waste dumping, causing regional ecosystem disorder. Using roof horizontal wells for mining and filling in large, high-yield and high-efficiency mines can solve a series of ecological problems in coal mining areas. Among them, horizontal wells are mainly used as channels for conveying paste double slurry during mining and filling. During the filling process, the double slurry needs to be fully stirred. At the same time, due to the limited coverage of the filling slurry in the goaf, as the comprehensive mining face gradually advances, the outlet of the filling slurry needs to be continuously moved forward. Therefore, it is required to perform fixed-point cutting of the slurry conveying pipeline in the goaf. At present, there are no cases at home and abroad for devices that integrate cutting and mixing in narrow spaces.

[0003] On the one hand, conventional mixers are driven by motors to mix multiple slurries. However, due to their large size and large space occupation, they form barriers to the paste and double slurries and are not suitable for horizontal holes. In addition, the paste and double slurries solidify during the transportation process, causing pipe blockage and bursting, further reducing work efficiency.

[0004] Secondly, the fixed-point cutting of the casing currently mainly includes conventional hydraulic cutter cutting. This cutting method has certain safety risks because sparks are easily generated during the cutting process.

[0005] Thirdly, cutting and mixing are two relatively independent processes. The construction process is complicated and requires repeated lifting and lowering of pipes, which is time-consuming and labor-intensive, seriously affecting the efficiency of construction.

[0006] Therefore, in view of the above problems, the design of the present invention, through intensive research and careful design, has developed a tool that can meet the needs of conveying paste slurry and cutting casing at a fixed point, so that the tool can cut the casing in sections once entering the well, and at the same time achieve uniform mixing of the two slurries. Summary of the invention

[0007] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a device and method for cutting and mixing casing in a horizontal wellbore to solve the problems in the prior art.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0009] A casing cutting and mixing filling device in a horizontal wellbore, comprising a cutting mechanism and a mixing mechanism, wherein the cutting mechanism comprises a rotating body and an injection port, wherein the rotating body is provided with a mounting groove along its axial direction, and the injection port is provided on the rotating body along the circumference of the rotating body, and the mounting groove is communicated with the injection port, and the cutting fluid can enter the mounting groove to drive the rotating body to rotate and be ejected through the injection port;

[0010] The mixing mechanism comprises a shell, which is rotatably connected to one end of the rotating body away from the mounting groove, a grouting hole is arranged at one end of the shell close to the injection port, the grouting hole is communicated with the injection port, and an outlet is arranged at the other end of the shell.

[0011] Preferably, a rotatable connecting shaft is provided between the rotating body and the shell, a gear is provided at one end of the connecting shaft and the rotating body, a bearing is provided at one end of the connecting shaft and the shell, the gear and the bearing are concentrically arranged, and damping grease is coated on the gear and the bearing ball to control the rotation speed of the rotating body.

[0012] Preferably, an anchoring seal is provided between the shell and the connecting shaft.

[0013] Preferably, the injection port is arranged at an angle of 45 degrees to the rotating body, and the injection port is arranged toward one side of the shell.

[0014] Preferably, the device for cutting casing and mixing and filling in a horizontal wellbore further comprises a guide, and the shell outlet is arranged on the guide.

[0015] Preferably, a plurality of first righting wings are arranged on the outer wall of the shell along the axial circumference thereof, and a rotating sheet is arranged inside the shell.

[0016] Preferably, the device for cutting and mixing casing in the horizontal wellbore also includes a delivery pipe, which includes a core shaft, a pipe body, a first joint, and a second joint. A delivery hole is arranged in the core shaft, one end of the core shaft is connected to the rotating body and the delivery hole is communicated with the mounting groove, the first joint and the second joint are respectively sleeved on the two ends of the core shaft, the delivery pipe extends out of the second joint, the pipe body is sleeved on the first joint, the second joint and the core shaft, and is used to fix the first joint, the second joint and the core shaft, and sealing rings are arranged between the pipe body and the core shaft, the first joint and the second joint, and the pipe body is connected to the first joint and the second joint by a first screw.

[0017] Preferably, the tube body is provided with a plurality of second righting wings along its axial circumference.

[0018] Preferably, the core shaft is connected to the rotating body via a conversion joint.

[0019] A method for cutting and mixing casing in a horizontal wellbore, and a device for cutting and mixing casing in a horizontal wellbore, the method comprising the following steps:

[0020] Step 1: Connect the pipe string to the first joint, and before the casing cutting and mixing filling device in the horizontal wellbore enters the wellbore, perform a ground pressure test on it to test the rotation of the rotating body in the cutting mechanism and confirm the cutting construction pressure parameters of the cutting mechanism. After the pressure test, slowly lower the casing cutting and mixing filling device into the horizontal well through the orifice;

[0021] Step 2: connect the ground water tank, high-pressure pump, and high-pressure abrasive tank in sequence through pipelines, connect the high-pressure abrasive tanks with the casing cutting and mixing filling device through a pipe string, and install a wellhead device;

[0022] Step 3: After the casing cutting and mixing filling device is lowered into the predetermined cutting section, the anchoring mechanism is fixed and the pipe string and the casing annulus are sealed by lifting and lowering. After the anchoring and sealing are completed, the cutting fluid is transported to the rotating body installation groove through the pipe string by using a ground high-pressure pump. The cutting fluid enters the rotating body under the action of high pressure (pressure is 30-40MPa) to drive the rotating body to rotate at high speed, so that the cutting fluid is ejected from the injection port to cut the first section of the casing;

[0023] Step 4: After the first section of casing is cut, repeat step 3, lift the pipe string according to the position of the cut section, and cut the horizontal section of casing in sequence.

[0024] Step 5: After the segmented cutting is completed, the tool string is lowered to the first section of the casing, and the double slurry is injected through the ground paste filling pump and the high-pressure pump. The slurry injected by the high-pressure pump sprays high-pressure liquid through the injection port of the rotating body to break up the paste slurry, and the double slurry is then evenly mixed through the mixing mechanism;

[0025] Step 6: After the filling of the first section of casing is completed, the pipe string is lifted to the second section cutting position, and the above step 5 is repeated to complete the filling of the second section;

[0026] Step 7: Repeat steps 5 and 6 to complete the filling of the paste slurry in the horizontal well.

[0027] Compared with the prior art, the present invention has the following technical effects:

[0028] (I) The device for cutting and mixing casing in a horizontal wellbore of the present invention connects the installation groove to the pipe string, and the high-pressure pump can deliver high-pressure cutting fluid through the pipe string into the rotating body. The rotating body rotates under the impetus of the high-pressure cutting fluid, and the high-pressure cutting liquid is ejected from the injection port to achieve casing cutting. Then, the slurry is delivered to the installation groove by the high-pressure pump. At the same time, the paste slurry is injected into the channel formed between the rotating body and the casing by the paste filling pump. The paste slurry is mixed with the slurry and then enters the shell through the grouting hole and flows out from the outlet into the well to be filled. The purpose of integrating casing cutting and mixing and filling is achieved in the goaf. During construction, casing cutting and mixing and filling can be achieved by lowering the pipe column only once, which saves time and has high work efficiency. The device of the present invention is safe, and the mixing of the paste and double slurries in the shell effectively avoids the phenomenon of pipe blockage and pipe burst when it is transported from the wellhead through a pipeline. At the same time, during the filling process, the high-speed slurry sprayed from the injection port of the cutting device is used to break up the viscous slurry containing aggregates, and then the double slurries are evenly mixed through the mixing device to achieve the purpose of integrating cutting and mixing. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of the casing cutting and mixing filling device of the present invention;

[0030] Figure 2 It is a schematic structural diagram of the cutting mechanism of the present invention;

[0031] Figure 3 is an AA cross-sectional side view of the present invention;

[0032] Figure 4 is a BB cutaway side view of the present invention;

[0033] Figure 5 is a schematic diagram of the bearing structure of the present invention;

[0034] Figure 6 It is a CC cross-sectional side view of the present invention.

[0035] The meaning of each number in the figure is:

[0036] 1-cutting mechanism, 2-mixing mechanism, 3-rotating body, 4-injection port, 5-shell, 6-grouting hole, 7-outlet, 8-connecting shaft, 9-gear, 10-bearing, 11-anchor, 12-guide, 13-first righting wing, 14-conveying pipe, 15-core shaft, 16-tube body, 17-first joint, 18-second joint, 19-second righting wing, 20-conversion joint, 21-sealing ring, 22-first screw, 23-end cover, 24-second screw, 25-speed limiting ring, 26-boss, 27-third joint, 28-ball, 29-groove, 31-rotating plate.

[0037] The specific contents of the present invention are further explained in detail below in conjunction with embodiments. DETAILED DESCRIPTION

[0038] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0039] The directional terms mentioned in this document, such as "lateral", "radial", "axial" and "circumferential", are consistent with the specific directions on the paper of the drawings in the specification or the corresponding directions in the space shown in the drawings.

[0040] Embodiment 1:

[0041] A casing cutting and mixing filling device in a horizontal wellbore, such as Figure 1-6 As shown, it includes a cutting mechanism 1 and a mixing mechanism 2, wherein the cutting mechanism 1 includes a rotating body 3 and an injection port 4, wherein the rotating body 3 is provided with a mounting groove along its axial direction, and the injection port 4 is provided on the rotating body 3 along the circumference of the rotating body 3, and the mounting groove is communicated with the injection port 4, and the cutting fluid can enter the mounting groove to drive the rotating body 3 to rotate and be ejected through the injection port 4;

[0042] The mixing mechanism 2 includes a shell 5, which is rotatably connected to one end of the rotating body 3 away from the mounting groove. A grouting hole 6 is arranged at one end of the shell 5 close to the injection port 4, and the grouting hole 6 is communicated with the injection port 4. An outlet 7 is arranged at the other end of the shell 5.

[0043] Among them, the device for cutting and mixing casing in the horizontal wellbore of this embodiment connects the installation groove with the pipe string, and the high-pressure pump can transport the high-pressure cutting fluid into the rotating body through the pipe string. The rotating body rotates under the impetus of the high-pressure cutting fluid, and the high-pressure cutting liquid is ejected from the injection port to achieve the cutting of the casing. Then, the slurry is transported into the installation groove by the high-pressure pump. At the same time, the paste slurry is injected into the channel formed between the rotating body and the casing by the paste filling pump. After the paste slurry is mixed with the slurry, it enters the shell through the grouting hole and flows out from the outlet into the filling medium to be filled. The wellbore is filled, so the purpose of combining casing cutting and mixing and filling is achieved. During construction, only one pipe string is needed to achieve casing cutting and mixing and filling, which saves time and has high work efficiency. The device and equipment of this embodiment are safe, and the mixing of the paste and double slurries in the shell effectively avoids the phenomenon of pipe blockage and pipe burst when it is transported from the wellhead through the pipeline. At the same time, during the filling process, the high-speed slurry sprayed from the injection port of the cutting device is used to break up the viscous slurry containing aggregate, and then the double slurries are evenly mixed through the mixing device to achieve the purpose of cutting and mixing in one.

[0044] The slurry of this embodiment uses an accelerating agent to accelerate the solidification of the paste and improve the filling efficiency. The cutting fluid is a liquid containing an abrasive, and the abrasive can be quartz sand, corundum, etc. The paste is a filler, which is mainly composed of coal gangue, fly ash, cement, etc.

[0045] As a preferred solution of this embodiment, a rotatable connecting shaft 8 is provided between the rotating body 3 and the shell 5, a gear 9 is provided at one end of the connecting shaft 8 connected to the rotating body 3, a bearing 10 is provided at one end of the connecting shaft 8 connected to the shell 5, the gear 9 and the bearing 10 are concentrically arranged, and damping grease is coated on the balls of the gear 9 and the bearing 10 for controlling the rotation speed of the rotating body to prevent the rotation speed of the rotating body from being too high and causing atomization to affect the effect of cutting the casing.

[0046] Among them, a third connecting head 27 is arranged between the connecting shaft 8 and the rotating body 3, an end cover 23 is arranged on the connecting shaft 8, the end cover 23 and the third connecting head are fixed by a second screw 24, a speed limiting ring 25 is arranged inside the end cover 23, and the gear is arranged in the speed limiting ring 25. The gear is coated with damping grease to limit the larger rotation speed of the rotating body to prevent atomization from affecting the cutting efficiency.

[0047] Four bosses 26 are arranged on the bearing 10, and a fourth connector is arranged at one end of the connecting shaft 8 connected to the housing. The fourth connector is used to connect to the housing. The fourth connector contains four grooves 29 for connecting to the bosses 26 of the bearing 10. A circle of balls 28 are arranged inside the bearing 10, and damping grease is also applied between the balls 28 to reduce the rotation speed of the rotating body of the cutting device.

[0048] As a preferred solution of this embodiment, an anchoring seal 11 is arranged between the shell 5 and the connecting shaft 8. The existing anchoring seal adopts one of the existing self-sealing type, compression type and expansion type. This example takes the compression anchoring device as an example. When setting the seal, the oil pipe is lifted to a certain height and the pipe string is lowered. The cone opens the cava to clamp the casing wall, and the compression rubber sleeve seals the annular space of the oil casing; when unsealing, the pipe string is lifted, and the upper joint and the center pipe are moved upward together. When the sliding ring pin moves to the bottom dead point, the cone withdraws, the cava is retracted to release the jam, and the rubber sleeve is also retracted to unseal.

[0049] As a preferred solution of this embodiment, the injection port 4 is arranged at an angle of 45 degrees to the rotating body 3, and the injection port (4) is arranged toward one side of the shell (5).

[0050] Among them, the injection port 4 of this embodiment is a nozzle, and the injection port 4 is set at an angle of 45 degrees with the rotating body 3, so that the injection effect can be optimized. The injection port (4) is set toward the side of the shell (5), so that the nozzle can spray along the direction of the paste flow, which not only has the effect of crushing the paste aggregate, but also has the effect of breaking up the viscous paste slurry.

[0051] As a preferred solution of this embodiment, the device for cutting casing and mixing and filling in a horizontal wellbore further includes a guide 12 , and the outlet 7 of the shell 5 is arranged on the guide 12 .

[0052] The guide 12 is used for guiding the tool string downhole.

[0053] As a preferred solution of this embodiment, a plurality of first righting wings 13 are arranged on the outer wall of the shell 5 along the axial circumference thereof, and a rotating piece 31 is arranged inside the shell.

[0054] Among them, a first straightening wing is arranged to keep the shell centered during the process of entering the well and during operation, thereby ensuring the efficiency of mixing and filling. The rotating plate 31 is arranged inside the shell 5 to make the slurry rotate left and right from time to time during the flow of the double slurry, constantly changing the flow direction, thereby causing uniform mixing of the double slurries.

[0055] As a preferred solution of this embodiment, the device for casing cutting and mixing and filling in the horizontal wellbore also includes a delivery pipe 14, which includes a core shaft 15, a pipe body 16, a first joint 17, and a second joint 18. A delivery hole is provided in the core shaft 15, one end of the core shaft 15 is connected to the rotating body 3 and the delivery hole is communicated with the mounting groove, the first joint 17 and the second joint 18 are respectively sleeved on the two ends of the core shaft 15, the delivery pipe extends out of the second joint 18, the pipe body 16 is sleeved on the first joint 17, the second joint 18 and the core shaft 15, and is used to fix the first joint 17, the second joint 18 and the core shaft 15, and sealing rings 21 are provided between the pipe body 16 and the core shaft 15, the first joint 17, and the second joint 18, and the pipe body 16 is connected to the first joint 17 and the second joint 18 by a first screw 22.

[0056] As a preferred solution of this embodiment, the tube body 16 is provided with a plurality of second righting wings 19 along its axial circumference.

[0057] Among them, the second straightening wing is used to keep the cutting tool centered during the cutting process, ensuring the cutting uniformity of the cutting process and improving the cutting efficiency.

[0058] As a preferred solution of this embodiment, the core shaft 15 is connected to the rotating body 3 via a conversion joint 20, which has the function of replacing the rotating body and the nozzle according to different cutting sizes.

[0059] Embodiment 2:

[0060] This embodiment takes a coal mine in Northwest China as an example. The coal seam is buried at a depth of 400m to 500m, the coal seam thickness is about 3m, the working face width is 200m to 300m, the working face length is 2000m to 3000m, the coal seam roof is 4m to 5m thick mudstone (sandy mudstone and silty mudstone), and two L-shaped horizontal wells are constructed on the coal seam roof. Taking one horizontal well as an example, a method for cutting and mixing casing in a horizontal wellbore is adopted. The device for cutting and mixing casing in a horizontal wellbore of Embodiment 1 is adopted. The method comprises the following steps:

[0061] Step 1: Connect the pipe string to the second joint, and before the casing cutting and mixing filling device in the horizontal wellbore enters the wellbore, perform a ground pressure test (test pressure 20-30MPa) on it, test the rotation of the rotating body in the cutting mechanism, and confirm the cutting construction pressure parameters of the cutting mechanism. After the pressure test is completed, slowly lower the casing cutting and mixing filling device into the horizontal well through the orifice;

[0062] Step 2: connect the ground water tank, high-pressure pump, and high-pressure abrasive tank in sequence through pipelines, connect the high-pressure abrasive tanks with the casing cutting and mixing filling device through a pipe string, and install a wellhead device;

[0063] Step 3: After the casing cutting and mixing filling device is lowered into the predetermined cutting section, the anchoring mechanism is fixed and the pipe string and the casing annulus are sealed by lifting and lowering. After the anchoring and sealing are completed, the cutting fluid is transported to the rotating body installation groove through the pipe string by using a ground high-pressure pump. The cutting fluid enters the rotating body under the action of high pressure and drives the rotating body to rotate at a high speed, so that the cutting fluid is ejected from the injection port to cut the first section of the casing;

[0064] Step 4: After the first section of casing is cut, repeat step 3, lift the pipe string according to the position of the cut section, and cut the horizontal section of casing in sequence.

[0065] Step 5: After the segmented cutting is completed, the tool string is lowered to the first section of the casing, and the double slurry is injected through the ground paste filling pump and the high-pressure pump. The slurry injected by the high-pressure pump sprays high-pressure liquid through the injection port of the rotating body to break up the paste slurry, and the double slurry is then evenly mixed through the mixing mechanism;

[0066] Step 6: After the filling of the first section of casing is completed, the pipe string is lifted to the second section cutting position, and the above step 5 is repeated to complete the filling of the second section;

[0067] Step 7: Repeat steps 5 and 6 to complete the filling of the paste slurry in the horizontal well.

[0068] In this embodiment, the device and method provided by the present invention are used to fill the gap in the cutting and mixing devices in horizontal wellbores at home and abroad, and the cutting and mixing efficiency of mine filling work is improved by more than 80%.

Claims

1. A casing cutting and mixing filling device in a horizontal wellbore, comprising a cutting mechanism (1) and a mixing mechanism (2), wherein the cutting mechanism (1) comprises a rotating body (3) and an injection port (4), wherein the rotating body (3) is provided with a mounting groove along its axial direction, and the injection port (4) is provided on the rotating body (3) along the circumference of the rotating body (3), the mounting groove and the injection port (4) are communicated, and a cutting fluid can enter the mounting groove to drive the rotating body (3) to rotate and be ejected through the injection port (4); The mixing mechanism (2) comprises a shell (5), the shell (5) being rotatably connected to an end of the rotating body (3) away from the mounting groove, a grouting hole (6) being provided at an end of the shell (5) close to the injection port (4), the grouting hole (6) being in communication with the injection port (4), and an outlet (7) being provided at the other end of the shell (5); A rotatable connecting shaft (8) is provided between the rotating body (3) and the housing (5); a gear (9) is provided at one end of the connecting shaft (8) and the rotating body (3); a bearing (10) is provided at one end of the connecting shaft (8) and the housing (5); the gear (9) and the bearing (10) are concentrically arranged, and damping grease is applied on the balls of the gear (9) and the bearing (10) to control the rotation speed of the rotating body; A plurality of first righting wings (13) are arranged on the outer wall of the shell (5) along the axial circumference thereof, and a rotating sheet (31) is arranged inside the shell.

2. The casing cutting and mixing filling device in a horizontal wellbore according to claim 1, characterized in that: An anchoring packing (11) is provided between the shell (5) and the connecting shaft (8).

3. The casing cutting and mixing filling device in a horizontal wellbore according to claim 1, characterized in that: The injection port (4) is arranged at an angle of 45 degrees to the rotating body (3), and the injection port (4) is arranged toward one side of the housing (5).

4. The casing cutting and mixing filling device in a horizontal wellbore according to claim 1, characterized in that: The casing cutting and mixing filling device in a horizontal wellbore further comprises a guide (12), and an outlet (7) of the housing (5) is arranged on the guide (12).

5. The casing cutting and mixing filling device in a horizontal wellbore according to claim 4, characterized in that: The casing cutting and mixing filling device in a horizontal wellbore further comprises a delivery pipe (14), the delivery pipe (14) comprising a core shaft (15), a pipe body (16), a first joint (17), and a second joint (18); a delivery hole is arranged in the core shaft (15); one end of the core shaft (15) is connected to the rotating body (3) and the delivery hole is communicated with the mounting groove; the first joint (17) and the second joint (18) are respectively sleeved on the two ends of the core shaft (15); the delivery pipe extends out of the second joint (18) and is arranged; the pipe body (16) is sleeved on the first joint (17), the second joint (18) and the core shaft (15) and is used to fix the first joint (17), the second joint (18) and the core shaft (15); sealing rings (21) are arranged between the pipe body (16) and the core shaft (15), the first joint (17), and the second joint (18); and the pipe body (16) and the first joint (17) and the second joint (18) are connected by a first screw (22).

6. The casing cutting and mixing filling device in a horizontal wellbore according to claim 5, characterized in that: The tube body (16) is provided with a plurality of second righting wings (19) along its axial circumference.

7. The casing cutting and mixing filling device in a horizontal wellbore according to claim 6, characterized in that: The core shaft (15) is connected to the rotating body (3) via a conversion joint (20).

8. A method for cutting and mixing casing in a horizontal wellbore, characterized in that: Using the casing cutting and mixing filling device in a horizontal wellbore as claimed in claim 7, the method comprises the following steps: Step 1: Connect the pipe string to the first joint, and before the casing cutting and mixing filling device enters the wellbore in the horizontal wellbore, perform a ground pressure test on it to test the rotation of the rotating body in the cutting mechanism and confirm the cutting construction pressure parameters of the cutting mechanism. After the pressure test, slowly lower the casing cutting and mixing filling device into the horizontal well through the orifice; Step 2: connect the ground water tank, high-pressure pump, and high-pressure abrasive tank in sequence through pipelines, connect the high-pressure abrasive tanks with the casing cutting and mixing filling device through a pipe string, and install a wellhead device; Step 3: After the casing cutting and mixing filling device is lowered into the predetermined cutting section, the anchoring mechanism is fixed and the pipe string and the casing annulus are sealed by lifting and lowering. After the anchoring and sealing are completed, the cutting fluid is transported to the rotating body installation groove through the pipe string by using a ground high-pressure pump. The cutting fluid enters the rotating body under the action of high pressure and drives the rotating body to rotate at a high speed, so that the cutting fluid is ejected from the injection port to cut the first section of the casing; Step 4: After the first section of casing is cut, repeat step 3, lift the pipe string according to the position of the cut section and cut the horizontal section of casing in sequence; Step 5: After the segmented cutting is completed, the tool string is lowered to the first section of the casing, and the double slurry is injected through the ground paste filling pump and the high-pressure pump. The slurry injected by the high-pressure pump sprays high-pressure liquid through the injection port of the rotating body to break up the paste slurry, and the double slurry is then evenly mixed through the mixing mechanism; Step 6: After the filling of the first section of casing is completed, the pipe string is lifted to the second section cutting position, and the above step 5 is repeated to complete the filling of the second section; Step 7: Repeat steps 5 and 6 to complete the filling of the paste slurry in the horizontal well.

Images