A downhole string perforating and radial cutting tool

Abstract

The application discloses a downhole pipe string perforating and radial cutting tool, which comprises an anchoring shell, a jet mechanism and a connecting rod. Four locking blocks are uniformly distributed in the side cavities of the anchoring shell, and the locking blocks can realize radial movement to clamp the pipe string wall and complete anchoring of the tool. The connecting rod can be connected with multiple jet mechanisms, and can realize one-time downhole operation of the tool to complete perforation of the multiple-level distributed spiral holes of the pipe string. A rotating shaft is connected with the jet mechanism through a key to drive the jet mechanism to rotate, high-temperature molten metal jet generated by aluminum thermal reaction is sprayed from the rotating nozzle, and the molten metal jet continuously acts on the outer metal pipe string to complete the circumferential cutting of the metal pipe string. The tool has simple structure, high cutting and unblocking efficiency, can realize multiple perforation and circumferential cutting operations on the downhole pipe string, and does not need subsequent auxiliary cutting treatment.

Description

A downhole tubing perforation and radial cutting tool Technical Field

[0001] This invention relates to the field of downhole tubing perforation and cutting tools, specifically a downhole tubing perforation and radial cutting tool. Background Technology

[0002] Drilling operations are frequently required for downhole tubing in oilfields, such as when the downhole tubing choke is blocked, or when a blockage cannot be retrieved due to wellbore issues, when circulation channels cannot be established between the casing and oil well, when fracturing tubing becomes stuck and sand flushing circulation channels cannot be established, or when drilling fluid circulation channels cannot be established after a stuck drill string. All these situations necessitate drilling into the tubing string. Furthermore, stuck drill accidents have become increasingly prominent in recent years. For small wellbores or drill pipes with excessively thick walls, traditional mechanical cutting cannot achieve rapid cutting operations, while explosive cutting can damage the wellbore and cause irregularities in the drill string top. To effectively solve these engineering problems, this invention provides a downhole tubing perforation and radial cutting tool. This tool utilizes a high-temperature molten metal jet generated by the aluminothermic reaction to achieve directional perforation or circumferential cutting of the downhole tubing string. Summary of the Invention

[0003] The purpose of this invention is to provide a new type of tool that can achieve downhole pipe perforation and radial cutting and unblocking of stuck pipes, especially suitable for rapid perforation of downhole pipes and cutting of thick-walled pipes that cannot be completed by traditional mechanical cutting.

[0004] The downhole tubing perforation and radial cutting tool used in this invention comprises a power supply 1, a power supply housing 2, an anchoring connecting section 3, a motor A4, a lead screw 5, an anchoring housing 6, an end cap 7, a cylindrical thrust body 8, a locking block 9, a thrust mechanism connecting section 10, a thrust mechanism housing 11, a fluid flow sleeve 13, a cylindrical pin 14, a jetting mechanism connecting section 15, a top cover 16, a motor B17, a rotating shaft 18, a rotating block 19, a key A20, and a key B21. It consists of: graphite plug 22, metal sleeve 23, jet mechanism housing 24, graphite heat insulation layer 25, conical guide body 26, fluid guide 27, metal frame 28, nozzle 29, commutator 30, metal gasket 31, sealing sleeve 32, connecting rod 33, spindle 34, straightening plate 35, screw 36, guide cone 37, slide rod 38, rolling bearing 39, distributed fluid guide 271, distributed nozzle 291, and distributed commutator 301.

[0005] In some embodiments, the upper thread of the anchoring housing 6 mates with the anchoring connection section 3, and the bottom thread mates with the propulsion mechanism connection section 10. Four rectangular through holes 6a are evenly spaced on the side to mate with the locking block end face 9c. The cylindrical pusher body 8 is inserted from the upper end of the anchoring housing so that its circumferential T-groove 8b mates with the locking block 9's T-shaped locking block 9a. The end cap 7 is secured to the step of the anchoring housing to hold the cylindrical pusher body 8 in place. A smooth circular through hole 6b is formed at the center of the lower end face of the anchoring housing to accommodate the remaining wheelbase of the lead screw. The lower end of the lead screw 5 is threaded into the cylindrical pusher body. The internal thread 8a engages with the locking block 9, and the locking block 9 has teeth 9b on its outside. These parts together form the anchoring mechanism, which can lock the pipe column by radial movement of the locking block to complete the tool anchoring operation; the upper and lower threads of the propulsion mechanism housing 11 are respectively threaded to the propulsion mechanism connecting section 10 and the injection mechanism connecting section 15. Eight outer water inlet holes 11a are evenly opened on the lower side, and there is a pin hole 11b at the upper end. A cylindrical through hole 11c is opened inside to accommodate the liquid flow sleeve 13. The liquid flow sleeve 13 has a liquid flow channel through hole 13a inside the lower end, and eight inner holes are evenly opened on the side. The water inlet 13b is positioned with the propulsion mechanism housing via a cylindrical pin. Thermite is filled in the cavity between the top of the fluid flow sleeve and the propulsion mechanism housing. Thermite is connected to a power lead; when electricity is applied, it ignites. The high-temperature, high-pressure gas generated by the thermite reaction creates thrust, shearing the cylindrical pin and causing the fluid flow sleeve to slide downwards until the two are coaxially aligned. At this point, the tool is interconnected internally and externally. External drilling fluid enters the tool and propels the graphite plug 22 downwards through a specially designed fluid flow channel, thereby pushing the remaining high-temperature molten metal jet out from the ejection mechanism, completing the process. Hydraulic propulsion operation; the upper and lower threads of the injection mechanism connecting short section 15 are respectively connected to the outer shell of the propulsion mechanism and the metal sleeve 23, the internal thread 15a is threadedly connected to the top cover 16, the upper through hole 15b stores the motor B17, the lower through hole 15c installs the rotating shaft, the through hole 15d is the liquid flow channel, the rotating block 19 is connected to the rotating shaft 18 through key B21, and is connected to the outer shell 24 of the injection mechanism through key A20. The motor B (17) is turned on to make the injection mechanism rotate, so that the jet is sprayed onto the tube column along the rotating flow channel to complete the radial cutting operation of the stuck tube column;The upper and lower ends of the injection mechanism housing 24 are fitted onto rolling bearings 39. The rolling bearings at both ends are respectively held in place by the injection mechanism connecting section and the metal sleeve. Inside the injection mechanism housing, a graphite plug 22, a graphite heat insulation layer 25, and a tapered guide body 26 are fitted. The lower end is threaded into the metal frame 28. The upper end of the guide fluid 27 has a tapered platform 27a with four evenly distributed speed-increasing flow channel through holes 27b. The lower end has a frame groove 27c. The upper and lower ends of the metal frame 28 are threaded to the injection mechanism housing 24 and the connecting rod 33, respectively. An internal guide fluid sleeve 28a is provided. A circular through hole 29a is provided in the center of the nozzle 29, and an internal guide fluid sleeve 29b is also provided. Four circular nozzles 29c are evenly distributed on the side. A commutator 30 is also present. The center has a circular through-hole 30a, and four arc-shaped drainage grooves 30b are evenly distributed on the side. A step 30c is provided on the lower end face to hold the nozzle 29. A metal gasket 31 is threaded into the bottom of the metal frame. The sealing sleeve 32 is positioned on the connecting rod 33 by a sealing ring during the well run. These parts together form the injection mechanism. Thermite is filled in the reaction chamber of the graphite insulation layer. Thermite is connected to the power supply lead. When electricity is applied, the thermite is ignited. The high-temperature and high-pressure gas generated by the thermite reaction forms a thrust, pushing open the sealing sleeve. The high-temperature molten metal fluid of the reaction product is sprayed through the injection mechanism channel onto the tubing string to complete the perforation or radial cutting operation of the tubing string. The guide fluid 27, nozzle 29, and commutator 30 can be changed according to the actual working conditions to achieve different numbers of perforations. Different perforation diameters and perforation methods, such as distributed fluid guides 271, distributed nozzles 291, and distributed commutators 301, can achieve distributed spiral perforation operations. The mandrel 34 is inserted into and locked inside the slide rod 38 from the upper end, and its lower end is threadedly connected to the guide cone 37. A straightening plate 35 is connected to the middle position of the mandrel 36.

[0006] In some embodiments, when perforating the downhole tubing, motor B17 is turned off, the injection mechanism is stopped from rotating, and the high-temperature molten metal fluid generated by the thermite reaction is injected from the fixed nozzle onto the tubing, continuously scouring and eroding the tubing until perforation is completed. The structure of the fluid guide 27, nozzle 29, and commutator 30 in the injection mechanism can be changed according to the actual working conditions to achieve different perforation methods. Perforation in the radial direction of the same toroidal surface can be achieved, with the number of perforations being 1-10. Multi-layer radial spiral distributed perforation can also be achieved, with the number of perforation toroidal layers being 1-10.

[0007] In some embodiments, a jetting mechanism is proposed that can achieve four radial perforations on the same annular surface. The outlet of the speed-increasing flow channel of the guide fluid 27 is on the same horizontal line. The upper inlet of the four arc-shaped guide grooves of the commutator 30 is in parallel contact with the outlet of the speed-increasing flow channel of the guide fluid 27. The nozzle on the nozzle 29 is coaxially aligned with the lower outlet of the four arc-shaped guide grooves of the commutator 30. The high-temperature molten metal fluid generated by the thermite reaction flows through the flow channel formed by the three components and is finally sprayed onto the tubing from the four nozzles on the nozzle 29 to complete the perforation.

[0008] In some embodiments, a jetting mechanism is proposed that can simultaneously achieve four-hole penetration of two different annular layers in the radial direction. The distributed guide fluid 271 differs from the guide fluid 27 in that it has eight speed-increasing flow channel through holes, and its outlet height is spirally distributed on two different horizontal planes. The eight arc-shaped guide grooves of the distributed commutator 301 are radially spirally distributed on two different annular layers, and the upper inlet of the guide grooves is matched with the speed-increasing flow channel outlet of the distributed guide fluid 271. The eight nozzles of the distributed nozzle 291 are also radially spirally distributed on two different annular layers and are matched with the lower outlet of the arc-shaped guide groove of the distributed commutator 301. The high-temperature molten metal fluid generated by the thermite reaction flows through the flow channel formed by the three and is finally sprayed from the nozzles on the distributed nozzle 291 onto the column, completing the distributed spiral perforation.

[0009] In some embodiments, the upper internal thread of the connecting rod 33 is connected to the lower thread of the metal skeleton 28, and the lower end face external thread is connected to the second injection mechanism. Depending on the specific working conditions, multiple injection mechanisms can be connected downwards, with the number of connections ranging from 2 to 40. Each injection mechanism is connected to a different ignition lead, and the thermite in the injection mechanism is ignited sequentially from bottom to top. This allows the tool to be lowered into the well once and ignited multiple times, thus penetrating the tubing to create a multi-layered distributed spiral through-hole.

[0010] In some embodiments, when radial cutting is performed on a stuck tubing string, two injection mechanisms are connected. First, the thermite in the second injection mechanism is activated to complete the perforation operation and establish a drilling fluid circulation channel. Then, motor B17 is turned on to rotate the injection mechanism, and the thermite in the first injection mechanism is activated again. The high-temperature molten metal jet generated by the reaction of the thermite is sprayed from the rotating nozzle onto the tubing wall. Through continuous scouring and erosion, the radial cutting operation on the same annular surface of the tubing string is completed, realizing the tubing string perforation and cutting operation can be completed at the same time when the tool is lowered into the well.

[0011] In some embodiments, the graphite plug 22, graphite heat insulation layer 25, conical guide 26, fluid guide 27, nozzle 29, and commutator 30 in the spraying mechanism are all parts made of graphite material, which can withstand temperatures above 3000°C. The outer shell 24, metal frame 28, and metal gasket 31 of the spraying mechanism are all high-strength metal parts, enabling the spraying mechanism to withstand high temperatures and high pressures. Attached Figure Description

[0012] Figure 1. Overall schematic diagram of a downhole tubing perforation and radial cutting tool;

[0013] Figure 2. Schematic diagram of the anchored shell structure;

[0014] Figure 3. Schematic diagram of the cylindrical thrust body structure;

[0015] Figure 4. Schematic diagram of the locking block structure;

[0016] Figure 5. Schematic diagram of the overall structure of the anchoring mechanism;

[0017] Figure 6. Schematic diagram of the outer shell structure of the propulsion mechanism;

[0018] Figure 7. Schematic diagram of the fluid flow sliding sleeve structure;

[0019] Figure 8. Schematic diagram of the connecting short section structure of the injection mechanism;

[0020] Figure 9. Schematic diagram of the fluid guide structure;

[0021] Figure 10 Schematic diagram of the metal skeleton structure;

[0022] Figure 11 Schematic diagram of nozzle structure;

[0023] Figure 12 Schematic diagram of commutator structure;

[0024] Figure 13 Schematic diagram of the jetting mechanism flow channel;

[0025] Figure 14 Schematic diagram of distributed fluid guide structure;

[0026] Figure 15 Schematic diagram of distributed nozzle structure;

[0027] Figure 16 Schematic diagram of distributed commutator structure;

[0028] In the diagram: 1 Power supply, 2 Power supply housing, 3 Anchoring connecting section, 4 Motor A, 5 Lead screw, 6 Anchoring housing, 7 End cover, 8 Cylindrical thrust body, 9 Locking block, 10 Propulsion mechanism connecting section, 11 Propulsion mechanism housing, 13 Fluid flow sleeve, 14 Cylindrical pin, 15 Jet mechanism connecting section, 16 Top cover, 17 Motor B, 18 Shaft, 19 Rotating block, 20 Key A, 21 Key B, 22 Graphite plug, 23 Metal sleeve, 24 Jet mechanism housing, 25 Graphite heat insulation layer, 26 Conical guide body, 27 Fluid guide, 28 Metal frame, 29 Nozzle, 30 Commutator, 31 Metal gasket, 32 Sealing sleeve, 33 Connecting rod, 34 Spindle, 35 Centralizing plate, 36 Screw, 37 Guide cone, 38 Slide rod, 39 Rolling bearing, 271 Distributed fluid guide, 291 Distributed nozzle, 301 Distributed commutator, 6a Anchoring housing side groove 6b Anchor housing lower end center through hole, 8a Cylindrical thrust body center hole thread, 8b Cylindrical thrust body T-slot, 9a Locking block T-slot, 9b Locking block teeth, 9c Locking block smooth end face, 11a Water inlet hole on the outer side of the propulsion mechanism housing, 11b Cylindrical pin hole, 11c Propulsion mechanism housing center inner hole, 13a Fluid flow sleeve fluid channel, 13b Fluid flow sleeve inner side water inlet hole, 15a Threaded middle section of the jet mechanism connecting short section. 15b The upper end through hole of the injection mechanism connecting short section; 15c The lower end through hole of the injection mechanism connecting short section; 15d Liquid flow channel; 27a Upper conical platform of the guide fluid; 27b Through hole of the guide fluid speed-increasing flow channel; 27c Skeleton groove; 28a Guide fluid sleeve; 29a Central circular hole of the nozzle; 29b Internal guide fluid sleeve of the nozzle; 29c Side nozzle; 30a Central circular through hole of the commutator; 30b Drainage groove; 30c Commutator step. Detailed Implementation

[0029] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0030] Example 1, as shown in Figures 1-16, a downhole tubing perforation and radial cutting tool includes an anchoring housing 6, a propulsion mechanism housing 11, and a jetting mechanism housing 24. Four locking blocks 9 are evenly distributed in four grooves on the side of the anchoring housing 6. The lower end of the anchoring housing 6 is threadedly connected to a propulsion mechanism connecting section 10. The propulsion mechanism connecting section 10 is connected to the upper end of the propulsion mechanism housing 11. A fluid flow sleeve 13 is positioned inside the propulsion mechanism housing 11 by a cylindrical pin. The jetting mechanism housing 24 is connected to a rotating block 19 via key A. The rotating block 19 is connected to a rotating shaft 18 via key B. Inside the jetting mechanism housing, a graphite plug 22, a graphite heat insulation layer 25, and a conical guide body 26 are fitted. These three graphite material components together constitute the reaction chamber of the thermite. A fluid guide 27, a metal skeleton 28, a nozzle 29, and a commutator 30 constitute the flame flow channel. The tool can perform tubing perforation and cutting / unjamming operations. The process of perforating the tubing involves tool anchoring, flame cutting, and hydraulic propulsion-assisted jetting. Based on this, starting motor B to rotate the jetting mechanism can complete the radial cutting and unblocking operation of the stuck tubing.

[0031] Example 2, as shown in Figures 1 to 5, based on Example 1, the structure for driving the locking block 9 to move radially is as follows: the upper thread of the anchoring housing 6 engages with the anchoring connection section 3, the bottom thread engages with the propulsion mechanism connection section 10, four rectangular through holes 6a are evenly opened on the side to engage with the locking block end face 9c, the cylindrical pusher body 8 is inserted from the upper end of the anchoring housing so that the oblique T-shaped groove 8b on its circumference engages with the oblique T-shaped locking block 9a of the locking block 9, the end cap 7 is locked on the step of the anchoring housing to hold the cylindrical pusher body 8, a smooth circular through hole 6b is opened at the center of the lower end face of the anchoring housing to accommodate the remaining shaft distance of the lead screw, the lower end of the lead screw 5 engages with the internal thread 8a of the cylindrical pusher body through the thread, and the locking block 9 has teeth 9b on its outside. These parts together form the anchoring mechanism. The motor A1 drives the lead screw 5 to rotate, forcing the cylindrical pusher body to move downward. During the movement, the cylindrical pusher body pushes out the locking block 9 and locks it on the pipe wall, completing the tool anchoring and locking.

[0032] Example 3, as shown in Figures 1 and 8, is based on Example 2. The structure for driving the rotation of the injection mechanism is as follows: the upper and lower threads of the injection mechanism connecting section 15 are respectively connected to the outer shell of the propulsion mechanism and the metal sleeve 23. The internal thread 15a is threadedly connected to the top cover 16. The upper through hole 15b houses the motor B17, the lower through hole 15c installs the rotating shaft, and the through hole 15d is the liquid flow channel. The rotating block 19 is connected to the rotating shaft 18 through key B21 and to the outer shell 24 of the injection mechanism through key A20. The upper and lower end faces of the injection mechanism outer shell 24 are fitted on the rolling bearings 39. The rolling bearings at both ends are held in place by the injection mechanism connecting section 15 and the metal sleeve 23, respectively. When the radial cutting and unblocking operation of the stuck pipe column is to be carried out, the motor B is turned on to make the injection mechanism rotate. The high-temperature molten metal fluid generated by the thermite reaction is sprayed from the rotating nozzle onto the pipe wall to complete the radial cutting of the pipe column.

[0033] Example 4, as shown in Figures 1 and 9-16, based on Example 3, the structure for high-temperature molten fluid injection is as follows: A graphite plug 22, a graphite heat insulation layer 25, and a conical guide body 26 are fitted inside the outer shell of the injection mechanism. The lower end is threaded into a metal skeleton 28. The upper end of the fluid guide 27 is provided with a conical platform 27a, with four evenly distributed speed-increasing flow channel through holes 27b inside. The lower end is provided with a skeleton slot 27c. The upper and lower ends of the metal skeleton 28 are threaded to the outer shell 24 of the injection mechanism and the connecting rod 33, respectively. A fluid guide sleeve 28a is opened inside. A circular through hole 29a is opened in the center of the nozzle 29, with evenly distributed fluid guide sleeves 29b inside. Four circular nozzles 29c are evenly distributed on the side. A circular through hole 30a is opened in the center of the commutator 30, with four evenly distributed arc-shaped nozzles on the side. The shaped drainage channel 30b has a step 30c on the lower end face to hold the nozzle 29. The metal gasket 31 is threaded with the bottom of the metal skeleton. The sealing sleeve (32) is positioned on the connecting rod 33 by the sealing ring during the well run. These parts together form the injection mechanism. Thermite is filled in the reaction chamber of the graphite insulation layer. Thermite is connected to the power supply lead. When the power is turned on, the thermite is ignited, so that the reaction product high temperature molten metal fluid is sprayed onto the tubing through the flow channel of the injection mechanism to complete the tubing perforation or radial cutting. The guide fluid 27, nozzle 29 and commutator 30 can be changed according to the actual working conditions to achieve different perforation numbers, different perforation diameters and different perforation methods. For example, the distributed guide fluid 271, distributed nozzle 291 and distributed commutator 301 can realize distributed spiral perforation operation.

[0034] Example 5, as shown in Figures 1, 6, and 7, based on Example 4, implements a hydraulically propelled assisted jet structure as follows: the upper and lower threads of the propulsion mechanism housing 11 are respectively threaded into the propulsion mechanism connecting section 10 and the jet mechanism connecting section 15. Eight outer water inlet holes 11a are evenly distributed on the lower side, and a pin hole (11b) is present at the upper end. A cylindrical through hole 11c is provided inside to accommodate the liquid flow sleeve (13). A liquid flow channel through hole 13a is provided inside the lower end of the liquid flow sleeve 13, and eight inner water inlet holes 13b are evenly distributed on the side. The pin is positioned with the housing of the propulsion mechanism. Thermite is filled in the cavity between the top of the fluid sliding sleeve and the housing of the propulsion mechanism. Thermite is connected to the power supply lead. When electricity is applied, the thermite is ignited. The high temperature and high pressure gas generated by the reaction of the thermite forms thrust, shearing the cylindrical pin and causing the fluid sliding sleeve to slide down until the two are coaxially aligned with the water inlet holes. At this time, the tool is interconnected inside and out. External drilling fluid enters the tool and propels the graphite plug 22 downward through a specially designed fluid channel, thereby pushing the residual high temperature molten metal jet out from the jetting mechanism to complete the hydraulic propulsion operation.

[0035] In summary: After the entire tool is lowered to the designated position on the tubing via cable, motor A is turned on, causing the lead screw to rotate. This forces the cylindrical pusher body to move downwards while simultaneously pushing out the locking block, which moves radially and locks onto the tubing, completing the anchoring. Further, when perforating the tubing, electricity is applied to ignite the thermite agent within the injection mechanism, causing it to burn and generate high-pressure gas and high-heat molten metal. Due to the internal and external pressure difference, the sealing sleeve is pushed open, and simultaneously, the high-heat molten metal is sprayed along the injection mechanism's flow channel onto the tubing. Through continuous scouring and erosion, perforation is completed. When radial perforation is applied to the stuck tubing... During the cutting and unblocking process, motor B is turned on to drive the spray mechanism to rotate, so that the high-temperature molten metal jet generated by the thermite reaction is sprayed from the rotating nozzle onto the pipe wall, completing the radial cutting of the pipe column. Further, the thermite in the outer shell cavity of the propulsion mechanism is ignited by electricity, causing it to burn and generate high-pressure gas, forming a thrust to shear the cylindrical pin, allowing the liquid flow sleeve to slide down until the two are coaxially aligned with the water inlet hole. External fluid enters the tool and impacts the graphite plug along the liquid flow channel to make the graphite plug move down, so that all the molten fluid that was left inside the spray mechanism due to insufficient pressure at the end of combustion is sprayed out.

[0036] The specific embodiments described above are for illustrative purposes only and are not intended to limit the scope of this patent. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of this patent shall fall within the protection scope of this patent system.

Claims

1. A downhole tubing perforation and radial cutting tool, comprising a power supply (1), a power supply housing (2), an anchoring connection short section (3), a motor A (4), a lead screw (5), an anchoring housing (6), an end cap (7), a cylindrical thrust body (8), a locking block (9), a thrust mechanism connection short section (10), a thrust mechanism housing (11), a fluid flow sleeve (13), a cylindrical pin (14), a jetting mechanism connection short section (15), a top cover (16), a motor B (17), a rotating shaft (18), a rotating block (19), a key A (20), a key B (21), a graphite plug (22), a metal sleeve (23), a jetting mechanism housing (24), a graphite heat insulation layer (25), a conical guide body (26), a fluid guide (27), and a metal skeleton (28). The structure consists of a nozzle (29), a commutator (30), a metal gasket (31), a sealing sleeve (32), a connecting rod (33), a spindle (34), a centralizing plate (35), a screw (36), a guide cone (37), a slide rod (38), a rolling bearing (39), a distributed guide fluid (271), a distributed nozzle (291), and a distributed commutator (301). The upper thread of the anchoring housing (6) mates with the anchoring connection short section (3), and the bottom thread mates with the propulsion mechanism connection short section (10). Four rectangular through holes (6a) are evenly opened on the side to mate with the end face (9c) of the locking block. The cylindrical pusher body (8) is inserted from the upper end of the anchoring housing so that the oblique T-shaped groove (8b) on its circumference mates with the oblique T-shaped locking block (9a) of the locking block (9). The end cap (7) is secured on the step of the anchoring housing to hold the cylindrical pusher body (8). A smooth circular through hole (6b) is opened at the center of the lower end face of the anchoring housing to accommodate the remaining shaft distance of the lead screw. The lower end of the lead screw (5) is threaded to the internal thread (8a) of the cylindrical pusher body. The locking block (9) has teeth (9b) on its outside. These parts together form the anchoring mechanism, which can lock the tube column by radial movement of the locking block to complete the tool anchoring operation. The upper and lower threads of the propulsion mechanism housing (11) are threaded to the propulsion mechanism connecting section (10) and the jet mechanism connecting section (15) respectively. Eight outer water inlets (11a) are evenly opened on the lower side. There is a pin hole (11b) at the upper end. A cylindrical through hole (11c) is opened inside to accommodate the liquid flow sleeve (13). The lower end of the fluid flow sleeve (13) has a fluid flow channel through hole (13a) and eight inner water inlets (13b) are evenly opened on the side. It is positioned with the outer shell of the propulsion mechanism by a cylindrical pin. Thermite is filled in the cavity between the top of the fluid flow sleeve and the outer shell of the propulsion mechanism. Thermite is connected to the power supply lead. When the power is turned on, the thermite is ignited. The high temperature and high pressure gas generated by the reaction of the thermite forms a thrust, cuts the cylindrical pin, and the fluid flow sleeve (13) slides down, so that the outer water inlet (11a) and the inner water inlet (13b) are coaxially matched. At this time, the tool is interconnected inside and outside. The external drilling fluid enters the tool and pushes the graphite plug (22) down through the specially designed fluid flow channel, thereby pushing the residual high temperature molten metal jet out from the jetting mechanism to complete the hydraulic propulsion operation.The upper and lower threads of the injection mechanism connecting short section (15) are respectively connected to the outer shell of the propulsion mechanism and the metal sleeve (23). The internal thread (15a) is connected to the top cover (16). The upper through hole (15b) houses the motor B (17), the lower through hole (15c) is used to install the rotating shaft, and the through hole (15d) is the liquid flow channel. The rotating block (19) is connected to the rotating shaft (18) through key B (21) and to the outer shell of the injection mechanism (24) through key A (20). When the motor B (17) is turned on, the injection mechanism rotates, so that the jet is sprayed onto the tube column along the rotating flow channel, completing the radial cutting operation of the stuck tube column. The upper and lower ends of the injection mechanism outer shell (24) are fitted with On the rolling bearing (39), the rolling bearings at both ends are respectively held in place by the injection mechanism connecting section and the metal sleeve. The injection mechanism housing is fitted with a graphite plug (22), a graphite heat insulation layer (25), and a conical guide (26). The lower end is threaded into the metal skeleton (28). The upper end of the guide fluid (27) is provided with a conical platform (27a), and four speed-increasing flow channel through holes (27b) are evenly distributed inside. The lower end is provided with a skeleton slot (27c). The upper and lower ends of the metal skeleton (28) are threaded to the injection mechanism housing (24) and the connecting rod (33) respectively. The guide fluid sleeve (28a) is opened inside. A circular through hole 1 (29a) is opened in the center of the nozzle (29). The internal fluid guide sleeve (29b) is also provided, and four circular nozzles (29c) are evenly distributed on the side. A circular through hole 2 (30a) is provided in the center of the commutator (30), and four arc-shaped drainage grooves (30b) are evenly provided on the side. A step (30c) is provided on the lower end face to hold the nozzle (29). The metal gasket (31) is threaded with the bottom of the metal skeleton. The sealing sleeve (32) is positioned on the connecting rod (33) by the sealing ring during the well run. These parts together form the injection mechanism. Thermite is filled in the reaction chamber of the graphite insulation layer. Thermite is connected to the power supply lead. When electricity is applied, the thermite is ignited. The high temperature and high pressure gas generated by the reaction of the thermite forms the thrust. Push open the sealing sleeve to allow the high-temperature molten metal fluid of the reaction product to be sprayed onto the tube column through the jetting mechanism, completing the tube column perforation or radial cutting operation; the guide fluid (27), nozzle (29), and commutator (30) can be changed according to the actual working conditions to achieve different perforation numbers, different perforation diameters, and different perforation methods. For example, the distributed guide fluid (271), distributed nozzle (291), and distributed commutator (301) can achieve distributed spiral perforation operation. The mandrel (34) is inserted from the upper end of the slide rod (38) and locked inside it. The lower end is threadedly connected to the guide cone (37), and the centering plate (35) is connected to it with a screw (36) in the middle position.

2. The downhole tubing perforation and radial cutting tool according to claim 1, characterized in that: When perforating the downhole tubing, motor B (17) is turned off, the injection mechanism is stopped from rotating, and the high-temperature molten metal fluid generated by the thermite reaction is injected from the fixed nozzle onto the tubing, continuously scouring and eroding the tubing until the perforation is completed. The structure of the fluid guide (27), nozzle (29), and commutator (30) in the injection mechanism can be changed according to the actual working conditions to achieve different perforation methods. Perforation in the radial direction of the same annular surface can be achieved, with the number of perforations ranging from 1 to 10. Multi-layer radial spiral distributed perforation can also be achieved, with the number of perforation annular layers ranging from 1 to 10.

3. The downhole tubing perforation and radial cutting tool according to claim 1, characterized in that: A jetting mechanism capable of achieving four radial perforations on the same annular surface is proposed. The outlet of the speed-increasing flow channel of the guide fluid (27) is on the same horizontal line. The upper inlet of the four arc-shaped guide grooves of the commutator (30) is parallel to the outlet of the speed-increasing flow channel of the guide fluid (27). The nozzle on the nozzle (29) is coaxially aligned with the lower outlet of the four arc-shaped guide grooves of the commutator (30). The high-temperature molten metal fluid generated by the thermite reaction flows through the flow channel formed by the three components and is finally sprayed onto the column from the four nozzles on the nozzle (29) to complete the perforation.

4. The downhole tubing perforation and radial cutting tool according to claim 1, characterized in that: A jetting mechanism is proposed that can simultaneously achieve four-hole penetration in two different annular layers in the radial direction. The difference between the distributed guide fluid (271) and the guide fluid (27) is that it has eight speed-increasing flow channel through holes, and its outlet height is spirally distributed on two different horizontal planes. The eight arc-shaped guide grooves of the distributed commutator (301) are radially spirally distributed on two different annular layers, and the upper inlet of the guide groove is matched with the speed-increasing flow channel outlet of the distributed guide fluid (271). The eight nozzles of the distributed nozzle (291) are also radially spirally distributed on two different annular layers and are matched with the lower outlet of the arc-shaped guide groove of the distributed commutator (301). The high-temperature molten metal fluid generated by the thermite reaction flows through the flow channel formed by the three and is finally sprayed from the nozzles on the distributed nozzle (291) onto the column to complete the distributed spiral perforation.

5. The downhole tubing perforation and radial cutting tool according to claim 1, characterized in that: The upper internal thread of the connecting rod (33) is connected to the lower thread of the metal skeleton (28), and the lower end face of the connecting rod (33) is connected to the second section of the injection mechanism. Depending on the specific working conditions, multiple injection mechanisms can be connected downwards, with a connection quantity of 2-40. Each injection mechanism is connected to a different ignition lead wire, and the thermite in the injection mechanism is ignited in sequence from bottom to top. This allows the tool to be lowered into the well once and ignited multiple times, and to penetrate the tubing to create a multi-layer distributed spiral through-hole.

6. The downhole tubing perforation and radial cutting tool according to claim 1, characterized in that: When radial cutting is performed on the stuck tubing, the two injection mechanisms are connected. First, the thermite in the second injection mechanism is activated to complete the perforation operation and establish a drilling fluid circulation channel. Then, motor B (17) is turned on to make the injection mechanism rotate. Finally, the thermite in the first injection mechanism is activated so that the high-temperature molten metal jet generated by the thermite reaction is sprayed from the rotating nozzle onto the pipe wall. After continuous scouring and erosion, the radial cutting operation of the same annular surface of the tubing is completed, so that the tool can be lowered into the well at one time and the tubing perforation and cutting operation can be completed at the same time.

7. The downhole tubing perforation and radial cutting tool according to claim 1, characterized in that: In the spraying mechanism, the graphite plug (22), graphite heat insulation layer (25), conical guide (26), fluid guide (27), nozzle (29), and commutator (30) are all made of graphite material and can withstand temperatures above 3000℃. The outer shell (24), metal frame (28), and metal gasket (31) of the spraying mechanism are all high-strength metal parts, enabling the spraying mechanism to withstand high temperature and high pressure.

Images