Recyclable fracturing fluid injection packing device

Abstract

The invention belongs to the technical field of hydraulic fracturing equipment, and particularly relates to a recoverable fracturing fluid injection packing device which comprises a rubber plug, a clamping mechanism, a main pipe body and an extrusion mechanism. The extrusion mechanism is composed of a threaded ejector rod and an extrusion rod, a hanging top disc is arranged on the threaded ejector rod, an extrusion disc is arranged on the extrusion rod, a top disc annular groove is formed in the end of the extrusion rod, and the hanging top disc is located in the top disc annular groove. The main pipe body is provided with a supporting column, a sliding groove and a hexagonal nut. The threaded ejector rod and the extrusion rod are mounted in the main pipe body; the rubber plug is sleeved on the main pipe body; the clamping mechanism comprises a chuck, a gear shaft, an inner gear ring and a sliding block, a circumferential sliding groove and an axial shaft hole are formed in the chuck, a rack is arranged in a square hole of the sliding block, the outer end of the sliding block is a wedge-shaped tip, outer teeth are arranged on the gear shaft, the sliding block is installed in the circumferential sliding groove, and the gear shaft is installed in the axial shaft hole. The tool adopts a mechanical extrusion packing method and can be repeatedly used, the consumption number of special steel pipes is reduced, and the curing time of epoxy resin is shortened.

Description

Technical Field

[0001] This invention belongs to the technical field of hydraulic fracturing equipment, specifically relating to a recyclable fracturing fluid injection and sealing device. Background Technology

[0002] Unconventional oil and gas reservoirs are generally low in porosity and permeability, requiring volumetric fracturing technology to improve formation conductivity for commercial exploitation. Before reservoir volumetric fracturing, true triaxial hydraulic fracturing experiments are necessary to investigate the propagation patterns of hydraulic fractures. To simulate the actual wellbore environment, true triaxial hydraulic fracturing experiments typically involve drilling a hole in the center of the rock sample, which is then sealed with a specially designed steel pipe and epoxy resin. Generally, a large number of hydraulic fracturing tests under various conditions are required to meet basic research needs, leading to a high consumption of specialized steel pipes and increased costs. Furthermore, the lengthy curing process of the epoxy resin prolongs the test preparation cycle and reduces overall research and development efficiency. Summary of the Invention

[0003] To address the problems existing in the background art, the present invention provides a recyclable fracturing fluid injection and sealing device to solve the problems of large consumption of special steel pipes and long epoxy resin curing time. The device is reusable, effectively controls test costs, significantly shortens the sealing waiting time, saves time, and improves the efficiency of fracturing experiments.

[0004] The technical solution adopted in this invention is: a recyclable fracturing fluid injection packer, which includes a rubber plug and a clamping mechanism. 、 Main body and extrusion mechanism; The extrusion mechanism consists of a threaded push rod and an extrusion rod. The outer end of the threaded push rod is provided with an external hexagonal connector, and the other end is provided with an external thread. The end of the external thread is provided with a hanging top plate. The extrusion rod is provided with evenly distributed extrusion plates. The extrusion plates are welded to the extrusion rod through two symmetrical connecting plates. The end of the extrusion rod is provided with a top plate annular groove, and the hanging top plate is located in the top plate annular groove. The main body is provided with support columns that are the same number as the extrusion discs and are evenly distributed. The spacing between the support columns is the same as the spacing between the extrusion discs. A sliding groove is opened on the main body on the right side of the support column, and a hexagonal nut is welded to the outside of the main body. The threaded push rod and the extrusion rod of the extrusion mechanism are installed in the main body, wherein the threaded push rod is threadedly connected to the main body, and the connecting plate connecting the extrusion plate is located in the groove; the number of rubber plugs is the same as that of the extrusion plate, and they are respectively fitted on the main body between the extrusion plate and the support column. The clamping mechanism includes a chuck, a gear shaft, an internal gear ring, and a slider. There are two chucks, each with circumferentially distributed circumferential grooves. Axial shaft holes are located on both sides of the circumferential grooves. A rack is installed within the square hole of the slider, and the outer end of the slider has a wedge-shaped tip. The gear shaft has three external teeth, and the outer end of the internal gear ring has a hexagonal head. The slider is installed within the circumferential grooves, and the gear shaft is installed in the axial shaft holes. The external teeth at the top of the gear shaft mesh with the internal teeth of the internal gear ring, and the other two external teeth mesh with the rack of the slider. The clamping mechanism is mounted on the main body between the hexagonal nut and the compression disc, and the chuck is embedded in the main body.

[0005] Furthermore, the rubber sealant is made of corrosion-resistant soft rubber material.

[0006] Furthermore, the number of support columns, extrusion discs, and rubber seals is three each.

[0007] Furthermore, each chuck has 8 circumferential grooves and 8 sliders.

[0008] Furthermore, the external hexagonal connector is provided with connecting threads for connecting to an external hydraulic fracturing device.

[0009] Furthermore, the slider of the clamping mechanism can be locked onto the rock hole in the core after sliding outward, thus fixing the entire device.

[0010] Furthermore, the extrusion disc is used to compress the rubber plug, causing the plug to expand outward and fill the hollow area of ​​the outer ring, blocking the outflow of fracturing fluid and preventing the fracturing fluid from eroding and precipitating.

[0011] The beneficial effects of this invention are as follows: It provides a recyclable fracturing fluid injection and packing device. This tool uses a mechanical extrusion packing method, which can be reused, reducing the consumption of special steel pipes, shortening the epoxy resin curing time, effectively controlling test costs, significantly reducing sealing waiting time, and improving fracturing experiment efficiency. Its main advantages are as follows: (1) The fracturing fluid injection packer reduces the consumption of special steel pipes and effectively controls the test cost by using corrosion-resistant rubber plugs and mechanical structures.

[0012] (2) The fracturing fluid injection packer adopts a mechanical extrusion sealing method, which greatly reduces the waiting time of traditional sealing and compresses the experimental preparation cycle.

[0013] (3) The fracturing fluid injection and sealing device adopts a mechanical fixing method, which can adapt to different rock pore sizes and is easy to promote and use in fracturing laboratories. Attached Figure Description

[0014] Figure 1This is a three-dimensional structural diagram of a fracturing fluid injection and packing device; Figure 2 This is a cross-sectional three-dimensional structural diagram of a fracturing fluid injection and packing device; Figure 3 This is a sectional three-dimensional structural diagram of the extrusion mechanism; Figure 4 This is a three-dimensional structural diagram of a threaded push rod; Figure 5 This is a sectional three-dimensional structural diagram of the extrusion rod; Figure 6 This is a schematic diagram of the connection between the threaded push rod and the pressing rod; Figure 7 This is a schematic diagram of the three-dimensional structure of the main body; Figure 8 This is a sectional three-dimensional structural diagram of the clamping mechanism; Figure 9 This is a sectional three-dimensional structural diagram of the chuck; Figure 10 This is a schematic diagram of the gear shaft and slider assembly; Figure 11 This is a three-dimensional structural diagram of the internal gear ring; Figure 12 This is a schematic diagram of the use of a fracturing fluid injection and sealing device in a rock core.

[0015] In the diagram, 1. Rubber seal, 2. Clamping mechanism, 3. Main body, 4. Extrusion mechanism, 20. Chuck, 21. Gear shaft, 22. Internal gear ring, 23. Hexagonal head, 24. Circumferential groove, 25. Axial shaft hole, 26. Slider, 27. Rack, 28. External gear, 29. Wedge-shaped tip, 31. Support column, 32. Groove, 33. Hexagonal nut, 41. Threaded push rod, 42. Extrusion rod, 43. Hexagonal connector, 44. Extrusion plate, 45. External thread, 46. Hanging top plate, 47. Top plate annular groove. Detailed Implementation Example

[0016] Referring to the figures, a recyclable fracturing fluid injection packer includes a rubber plug 1 and a clamping mechanism 2. 、 Main body 3 and extrusion mechanism 4.

[0017] The extrusion mechanism 4 consists of a threaded push rod 41 and an extrusion rod 42. The outer end of the threaded push rod 41 is provided with an external hexagonal connector 43, and the other end is provided with an external thread 45. The end of the external thread 45 is provided with a hanging top plate 46. The extrusion rod 42 is provided with evenly distributed extrusion plates 44. The extrusion plates 44 are welded to the extrusion rod 42 through two symmetrical connecting plates. The end of the extrusion rod 42 is provided with a top plate annular groove 47, and the hanging top plate 46 is located in the top plate annular groove 47.

[0018] The main body 3 is provided with the same number of support columns 31 as the extrusion discs 44 and evenly distributed. The spacing between the support columns 31 is the same as the spacing between the extrusion discs 44. A sliding groove 32 is opened on the main body 3 on the right side of the support column 31. A hexagonal nut 33 is welded to the outside of the main body 3.

[0019] The threaded push rod 41 and the extrusion rod 42 of the extrusion mechanism 4 are installed inside the main body 3, wherein the threaded push rod 41 is threadedly connected to the main body 3, and the connecting plate connecting the extrusion disc 44 is located in the slide groove 32; the number of rubber plugs 1 is the same as that of the extrusion disc 44, and they are respectively fitted on the main body 3 between the extrusion disc 44 and the support column 31.

[0020] The clamping mechanism 2 includes a chuck 20, a gear shaft 21, an internal gear ring 22, and a slider 26. There are two chucks 20. Each chuck 20 has a circumferentially distributed circumferential groove 24. The two sides of the circumferential groove 24 have axial shaft holes 25. The slider 26 has a rack 27 inside its square hole. The outer end of the slider 26 is a wedge-shaped tip 29. The gear shaft 21 has three external teeth 28. The outer end of the internal gear ring 22 has a hexagonal head 23. The slider 26 is installed in the circumferential groove 24. The gear shaft 21 is installed in the axial shaft hole 25. The external teeth 28 at the top of the gear shaft 21 mesh with the internal teeth of the internal gear ring 22. The other two external teeth 28 of the gear shaft 21 mesh with the rack 27 of the slider 26. The clamping mechanism 2 is fitted onto the main body 3 between the hexagonal nut 33 and the compression disc 44, and the chuck 20 is fixed to the main body 3.

[0021] The rubber plug 1 is made of corrosion-resistant soft rubber. There are three support columns 31, three extrusion discs 44, and three rubber plugs 1. Each chuck has eight circumferential grooves 24 and eight sliders 26. The external hexagonal connector 43 has connecting threads.

[0022] When using a recyclable fracturing fluid injection packer, the packer is placed inside the core borehole. One wrench is used to secure the packer to the hexagonal nut 33 of the main body 3, while another wrench is used to turn the hexagonal head 23 on the internal gear ring 22. Because the internal teeth of the internal gear ring 22 mesh with the external teeth 28 at the upper end of the gear shaft 21, the rotating internal gear ring 22 drives the gear shaft 21 to rotate. Since the other two external teeth 28 of the gear shaft 21 mesh with the racks 27 of the two sliders 26 respectively, the rotating gear shaft 21 drives the sliders 26 to move outward circumferentially. The wedge-shaped tip 29 of the outward-moving slider 26 engages with the borehole in the core, thus fixing the entire device inside the core. After the device is fixed, use a wrench to tighten the hexagonal connector 43 at the outer end of the threaded push rod 41. During rotation, the threaded push rod 41, which is threaded into the main body 3, rotates while the extrusion rod 42 is connected to the core via a disc-like arrangement. The threaded push rod 41 rotates, but the extrusion rod 42 does not rotate; it only moves axially. The extrusion rod 42, moving into the core, drives the extrusion disc 44 to move axially and compress the rubber plug 1. The rubber plug 1, compressed between the support column 31 and the extrusion disc 44, expands outward, filling the surrounding annular region. Then, the hydraulic fracturing device is connected to the hexagonal connector 43, and fracturing fluid is injected to begin the hydraulic fracturing experiment. After the experiment is completed, the hydraulic fracturing device is shut off, and the hexagonal connector 43 is rotated with a wrench, causing the extrusion rod 42 to move the extrusion disc 44 outward, and the rubber plug 1 rebounds. Then rotate the internal gear ring 22 to retract the slider 26 that clamps the rock core, and finally pull out the entire device.

[0023] The recyclable fracturing fluid injection packer uses a mechanical extrusion packing method, which solves the problems of large consumption of special steel pipes and long curing time of epoxy resin, significantly shortens the sealing waiting time, reduces costs, and improves the efficiency of fracturing experiments.

[0024] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A recyclable fracturing fluid injection packer, characterized in that: The recyclable fracturing fluid injection packer includes a rubber plug (1) and a clamping mechanism (2). 、 Main body (3) and extrusion mechanism (4); The extrusion mechanism (4) consists of a threaded push rod (41) and an extrusion rod (42). The outer end of the threaded push rod (41) is provided with an external hexagonal connector (43), and the other end is provided with an external thread (45). The end of the external thread (45) is provided with a hanging top plate (46). The extrusion rod (42) is provided with evenly distributed extrusion plates (44). The extrusion plates (44) are welded to the extrusion rod (42) through two symmetrical connecting plates. The end of the extrusion rod (42) is provided with a top plate annular groove (47). The hanging top plate (46) is located in the top plate annular groove (47). The main body (3) is provided with the same number of support columns (31) as the extrusion discs (44) and evenly distributed. The spacing between the support columns (31) is the same as the spacing between the extrusion discs (44). A sliding groove (32) is opened on the main body (3) on the right side of the support column (31). A hexagonal nut (33) is welded to the outside of the main body (3). The threaded push rod (41) and the extrusion rod (42) of the extrusion mechanism (4) are installed inside the main body (3), wherein the threaded push rod (41) is threadedly connected to the main body (3), and the connecting plate connecting the extrusion disc (44) is located in the slide groove (32); the number of rubber plugs (1) is the same as that of the extrusion disc (44), and they are respectively fitted on the main body (3) between the extrusion disc (44) and the support column (31); The clamping mechanism (2) includes a chuck (20), a gear shaft (21), an internal gear ring (22), and a slider (26). There are two chucks (20). The chucks (20) are provided with circumferentially distributed circumferential grooves (24). Axial shaft holes (25) are provided on both sides of the circumferential grooves (24). A rack (27) is provided in the square hole of the slider (26). The outer end of the slider (26) is a wedge-shaped tip (29). The gear shaft (21) is provided with three external teeth (28). The outer end of the internal gear ring (22) is provided with... It has a hexagonal head (23); the slider (26) is installed in the circumferential groove (24), the gear shaft (21) is installed on the axial shaft hole (25), the external teeth (28) at the top of the gear shaft (21) mesh with the internal teeth of the internal gear ring (22), and the other two external teeth (28) of the gear shaft (21) mesh with the rack (27) of the slider (26) respectively; the clamping mechanism (2) is fitted on the main body (3) between the hexagonal nut (33) and the extrusion plate (44), and the chuck (20) is fixed on the main body (3).

2. The recyclable fracturing fluid injection and packing device according to claim 1, characterized in that: The rubber plug (1) is made of corrosion-resistant soft rubber material.

3. The recyclable fracturing fluid injection and packing device according to claim 1, characterized in that: The number of the support column (31), the extrusion plate (44) and the rubber plug (1) are all three.

4. The recyclable fracturing fluid injection and packing device according to claim 1, characterized in that: Each chuck has 8 circumferential grooves (24) and 8 sliders (26).

5. The recyclable fracturing fluid injection packer according to claim 1, characterized in that: The external hexagonal connector (43) is provided with connecting threads.

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