Oil pipe perforating device

Abstract

The utility model provides an oil pipe perforating device which comprises a first gun head and a perforating gun assembly, a pipe cavity is formed in the first gun head, the perforating gun assembly comprises a gun body and an electric detonator, the gun body is connected with the first gun head and used for containing a detonating assembly, and the electric detonator is arranged in the pipe cavity and connected with the detonating assembly.

Description

Technical Field

[0001] The utility model relates to the technical field of oil pipe perforation technology in well completion operations, in particular to an oil pipe perforation device. Background Art

[0002] During the development of oil and gas fields, wellbore fluid accumulation is inevitable. When the accumulation reaches a certain level, it can cause the well to stop flowing. Gas lift is a common method for resolving wellbore fluid accumulation and plays a crucial role in gas field development. The technical principle is to inject gas through the casing to drain the accumulated fluid from the tubing through the oil-casing flow channel, allowing normal gas well production.

[0003] Currently, establishing a flow channel through the tubing and casing primarily involves inserting a gas lift valve during completion and perforating the tubing after production. Compared to inserting a gas lift valve during completion, tubing perforation offers greater flexibility in perforation depth, enabling optimization based on post-production data. This facilitates the implementation of gas lift and fluid removal techniques when surface gas supply pressure is limited. Furthermore, for wells where tubing is clogged and circulation kill is impossible, establishing a flow channel through the tubing and casing through perforation can achieve circulation kill, improving well control safety during workover operations.

[0004] To improve the liquid-carrying capacity of oil and gas wells, small tubing with an outer diameter of 73mm (inner diameter of 62mm) is primarily used for production operations in the later stages of oil and gas field development. The current tubing perforation process uses a Φ51mm perforating gun, conveyed by a cable for electric blasting. This process presents the following challenges for tubing with reduced diameters due to corrosion, scaling and wax deposition, adhesion of dirt such as sludge, and micro-deformation: First, the maximum outer diameter of the perforating gun is 54mm (at the gun end), and lowering the gun string with the cable can easily encounter resistance, often preventing the gun from reaching the intended position to perforate. Second, due to the expansion of the gun string after the perforating charge is detonated and the resulting perforation burrs, there is a risk of the gun becoming stuck when it is raised. Third, the Φ51mm perforating charge is powerful, and in wells with large well deviations or small cased casings, tubing perforation can damage the casing due to the close fit or small clearance between the tubing and the casing wall.

[0005] Therefore, it is desired in this field to provide an oil pipe perforation device to solve the above technical problems. Utility Model Content

[0006] The purpose of this utility model is to provide a tubing perforation device specifically designed for perforating small-diameter tubing. This device reduces its overall size to increase the gap between the device and the tubing's inner wall. This allows for easier and smoother lifting and lowering of tubing with reduced diameters caused by corrosion, scaling, wax deposition, sludge, and other debris, as well as minor deformation. This makes it easier to reach the desired perforation depth and complete the perforation operation.

[0007] According to the utility model, an oil pipe perforating device is provided, comprising a first gun head, wherein a lumen is formed in the first gun head.

[0008] A perforating gun assembly comprises a gun body connected to the first gun head and accommodating a detonating assembly, and an electric detonator arranged in the tube cavity and connected to the detonating assembly.

[0009] In one embodiment, the outer diameter of the perforating gun assembly is 40 mm.

[0010] In one embodiment, the gun body includes a shell connected to the first gun head, and a bomb rack disposed in the shell, and the detonation assembly includes a detonating cord disposed in the bomb rack.

[0011] In one embodiment, the detonation assembly further includes a booster tube disposed between the electric detonator and the detonating cord, and the booster tube is located in the housing.

[0012] In one embodiment, the detonation assembly further comprises a centralizing rod concentrically arranged in the gun body and abutting against the detonator tube, and the detonating cord is filled in the centralizing rod.

[0013] In one embodiment, a plurality of shooting holes are arranged at intervals along the length direction of the bomb rack.

[0014] In one embodiment, the plurality of perforations are staggered and distributed in a circumferential direction of the bomb rack.

[0015] In one embodiment, it is characterized in that the oil pipe perforating device further includes a second gun head arranged above the first gun head, and the first gun head is fixedly connected to the second gun head.

[0016] In one embodiment, the outer diameters of the first gun tip and the second gun tip are 44 mm.

[0017] In one embodiment, a detonator wire is provided at one end of the electric detonator away from the booster tube, and the detonator wire can extend out of the second gun head to be connected to a ground cable.

[0018] Compared with the prior art, the advantages of the present invention are:

[0019] This device is specifically designed for perforating small-diameter tubing by reducing the overall size of the device to increase the gap between the tubing perforator and the tubing's inner wall. This makes it easier and smoother to raise and lower tubing, even when it's reduced in diameter due to corrosion, scaling and wax deposition, sludge adhesion, and micro-deformation. This makes it easier to reach the designated perforation depth and complete the perforation operation. Furthermore, this method effectively protects the inner wall of the casing, promising broad prospects for widespread application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be described in detail below with reference to the accompanying drawings, in which:

[0021] Figure 1 The structure of the oil pipe perforating device according to the present invention is schematically shown;

[0022] Figure 2 It is a partial view of the oil pipe perforating device according to the utility model.

[0023] In the drawings, like parts are given like reference numerals, but the drawings are not necessarily drawn to scale. DETAILED DESCRIPTION

[0024] To make the technical solutions and advantages of the present invention more clearly understood, exemplary embodiments of the present invention are further described in detail below with reference to the accompanying drawings. It should be understood that the described embodiments are only a portion of the embodiments of the present invention, and are not exhaustive. Furthermore, the embodiments and features of the embodiments of the present invention may be combined with each other unless there is a conflict.

[0025] The present invention will be further described below with reference to the accompanying drawings.

[0026] Figure 1 The structure of the oil pipe perforating device 100 according to the present invention is schematically shown;

[0027] Figure 2 It is a partial view of the oil pipe perforating device 100 according to the present invention.

[0028] like Figure 1 and 2 As shown, the oil pipe perforating device 100 according to the present invention mainly includes a first gun head 11 and a perforating gun assembly. Preferably, a lumen 111 is formed in the first gun head 11. The perforating gun assembly includes a gun body connected to the first gun head 11 and an electric detonator 21. The gun body houses a detonating assembly, and the electric detonator 21 is installed in the lumen 111 and connected to the detonating assembly, thereby facilitating subsequent detonation transmission operations.

[0029] In this utility model, the outer diameter of the perforating gun assembly is 40mm. Therefore, when facing oil pipes with reduced diameters caused by reasons such as wall corrosion, scaling and wax deposition, adhesion of dirt such as sludge, and micro-deformation, this device can more smoothly complete the lifting and lowering operations, making it easier to reach the designated perforation depth and successfully carry out the perforation operation.

[0030] In one embodiment, Figure 1 and 2 As shown, the gun body includes a shell 31 connected to the first gun head 11, and a bomb rack 32 disposed in the shell 31. Preferably, the detonation assembly includes a detonating cord 22 and a booster tube 23, wherein the detonating cord 22 is mounted in the bomb rack 32, and the booster tube 23 is mounted in the shell 31. The booster tube 23 can connect the electric detonator 21 and the detonating cord 22 to effectively transmit the power.

[0031] Compared to the prior art, this device undergoes certain modifications to the perforating gun assembly to reduce its size, specifically reducing the overall dimensions of the housing 31 and the cartridge case 32. However, this would prevent the electric detonator 21 from being housed within the cartridge case 32. Therefore, this device features a custom-designed electric detonator 21 that can be installed within the lumen 111 of the first gun head 11 and connected in series with the detonating cord 22 via a booster tube 23 to ensure adequate detonation energy transfer.

[0032] This approach not only ensures the separate assembly of pyrotechnics and electrical components, but also solves the problem of electric detonator 21 being unable to be placed inside bomb rack 32. More importantly, this layout reduces the size of the device itself, making it easier to pass through reduced-diameter oil pipes to successfully complete the perforation operation, further ensuring the smooth implementation of processes such as gas lift dewatering and circulating well killing.

[0033] In one embodiment, Figure 1 and 2 As shown, the detonation assembly further includes a righting rod 24 concentrically arranged in the gun body and abutting against the booster tube 23. Preferably, the detonating cord 22 is filled in the righting rod 24, and the righting rod 24 can correct deviation in the device, thereby ensuring a good detonation energy transfer effect.

[0034] In one embodiment, Figure 1 and 2 As shown, a plurality of perforations 321 are arranged at intervals along the length of the bomb rack 32. Preferably, the detonating cord 22 can transfer the detonation energy into the bomb rack 32 and then eject the energy outward through the perforations 321 to complete the perforation operation.

[0035] Preferably, the plurality of perforations 321 are staggered in the circumferential direction of the bomb rack 32. This method can increase the working range of the perforation operation, fully utilize the detonation energy, and thus better complete the perforation operation, further ensuring the smooth implementation of processes such as gas lift drainage and circulating well killing.

[0036] In one embodiment, Figure 1 As shown, the oil pipe perforating device 100 further includes a second gun head 12 disposed above the first gun head 11. Preferably, the first gun head 11 and the second gun head 12 are fixedly connected, and in the present invention, the outer diameters of the first gun head 11 and the second gun head 12 are consistent.

[0037] Preferably, the outer diameters of the first and second gun tips 11 and 12 are both 44 mm. Therefore, when faced with oil pipes with reduced diameters due to reasons such as wall corrosion, scaling and wax deposition, adhesion of dirt such as sludge, and micro-deformation, the device can more smoothly complete the lifting and lowering operations, making it easier to reach the designated perforation depth and successfully perform the perforation operation.

[0038] In one embodiment, Figure 1 and 2 As shown, a detonator line 25 is provided at one end of the electric detonator 21 away from the booster tube 23. Preferably, the detonator line 25 can extend through the second gun head 12 to be connected to the ground cable for detonating the electric detonator 21.

[0039] This device is specially designed for perforating small-diameter oil pipes. Specifically, the outer diameters of the first and second gun tips 11, 12 have been reduced from 54mm to 44mm, while the outer diameter of the cartridge holder 32 has been reduced from 51mm to 40mm. This effectively increases the clearance between the oil pipe perforating device 100 and the inner wall of the oil pipe, enabling smoother and more efficient lifting and lowering operations, making it easier to reach the desired perforation depth.

[0040] The working process of this device is briefly described below:

[0041] First, after the assembled oil pipe perforating device 100 is lowered to the target depth via a cable, the electric detonator 21 is struck by ground power supply and cable power transmission; then, the detonation energy generated by the electric detonator 21 is smoothly transferred to the detonating cord 22 through the booster tube 23, and finally the detonation energy is released in the bomb rack 32, and then launched radially outward through the perforation 321 to complete the perforation operation.

[0042] Compared with the prior art, the advantages of the present invention are:

[0043] This device is specifically designed for perforating small-diameter tubing by reducing the overall device size to increase the gap between the tubing perforation device 100 and the tubing's inner wall. This makes it easier and smoother to raise and lower tubing with reduced diameters caused by corrosion, scaling and wax deposition, sludge, and other debris, as well as micro-deformation. This makes it easier to reach the designated perforation depth and complete the perforation operation. Furthermore, this method effectively protects the inner wall of the casing, promising broad prospects for widespread application.

[0044] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of such features.

[0045] In the present invention, unless otherwise clearly specified and limited, terms such as "installed", "connected", "connected", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two components.

[0046] For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0047] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art may easily make changes or modifications within the scope disclosed herein, and such changes or modifications shall be encompassed within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. An oil pipe perforating device, characterized in that: include: A first gun tip (11), wherein a lumen (111) is formed in the first gun tip (11), A perforating gun assembly, comprising a gun body connected to the first gun head (11) and accommodating a detonating assembly, and an electric detonator (21) disposed in the tubular cavity (111) and connected to the detonating assembly. The outer diameter of the perforating gun assembly is 40 mm. The oil pipe perforating device also includes a second gun head (12) arranged above the first gun head (11). The outer diameters of the first gun head (11) and the second gun head (12) are 44 mm. The gun body includes a shell (31) connected to the first gun head (11), and a bomb rack (32) arranged in the shell (31). The detonating assembly includes a detonating cord (22) arranged in the bomb rack (32). A plurality of perforations (321) arranged at intervals are provided along the length direction of the bomb rack (32).

2. The oil pipe perforating device according to claim 1, characterized in that: The detonation assembly further comprises a squib (23) arranged between the electric detonator (21) and the detonating cord (22), and the squib (23) is located in the housing (31).

3. The oil pipe perforating device according to claim 2, characterized in that: The detonating assembly further comprises a righting rod (24) which is concentrically arranged in the gun body and abuts against the detonator tube (23), and the detonating cord (22) is filled in the righting rod (24).

4. The oil pipe perforating device according to claim 3, characterized in that: The plurality of perforations (321) are staggered and distributed in the circumferential direction of the bomb rack (32).

5. The oil pipe perforating device according to claim 4, characterized in that: The first gun head (11) is fixedly connected to the second gun head (12).

6. The oil pipe perforating device according to claim 5, characterized in that: A detonator line (25) is provided at one end of the electric detonator (21) away from the detonator tube (23), and the detonator line (25) can extend through the second gun head (12) to be connected to a ground cable.

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