High-temperature-resistant shaped charge liner structure

Abstract

The application discloses a high-temperature-resistant shaped charge liner structure of a shaped charge perforator, and relates to the technical field of oil and gas well completion equipment, comprising a perforator shell, a liner assembly and a double-spherical surface self-centering coaxial support mechanism. The liner assembly is connected with the inner wall of the perforator shell through a spherical hinge, the double-spherical surface self-centering coaxial support mechanism is composed of an upper annular support seat and a lower annular support seat to form a spherical pair cooperation, the curvature center is coincident with the axis of the liner body, the spherical pair cooperation is continuously adhered through a cooperation elastic pre-tightening piece, and the spherical pair cooperation is automatically returned to normal under high-temperature micro-deformation. The application further adds circumferentially-distributed rigid claw bodies to form point contact supports, prevents high-temperature oval deformation and edge collapse of the liner, solves the problems of high-temperature deflection, deformation and asymmetric jet flow of a traditional liner, and has high centering precision and reliable structure, and is suitable for deep well, super-deep well, high-temperature and high-pressure oil and gas well completion perforation operations.

Description

Technical Field

[0001] This invention relates to the field of oil and gas well completion equipment technology, and more specifically, to a high-temperature resistant shaped charge perforator liner structure. Background Technology

[0002] The shaped charge perforator is a core piece of equipment for oil and gas well completion operations. Its working principle is to use the explosion of high-energy explosives to drive the metal of the shaped charge liner to converge, forming a high-speed jet that penetrates the casing and formation, establishing an oil and gas flow channel. With the continuous expansion of the development scale of deep wells, ultra-deep wells, and high-temperature and high-pressure oil and gas wells, the downhole operating temperature generally reaches 150℃~250℃. Traditional perforator shaped charge liners are prone to problems such as heat softening, local deformation, and assembly misalignment under long-term high-temperature environments.

[0003] Existing propellant liner systems mostly employ rigid support, interference fit, or simple limiting structures. When heated, the propellant liner is prone to elliptical deformation, mouth edge collapse, and axis misalignment, resulting in asymmetrical jet formation. Traditional support structures lack self-adaptive centering capabilities, making it difficult for the propellant liner to automatically return to center after misalignment, directly causing jet off-axis, gun wiping, and reduced piercing efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a high-temperature resistant shaped charge perforator liner structure. It adopts a double-spherical self-centering coaxial support mechanism, in which the curvature centers of the two sets of spherical pairs coincide with the axis of the liner. With the continuous pre-tensioning of high-temperature alloy disc springs, the liner can automatically return to center under high-temperature micro-deformation, thus avoiding jet deflection from the source. It has high centering accuracy and a simple and reliable structure.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A high-temperature resistant shaped charge perforator liner structure includes a liner assembly spherically hinged to the inner wall of the perforator cartridge case; the liner assembly includes a liner body and a double-spherical self-centering coaxial support mechanism; the double-spherical self-centering coaxial support mechanism includes an upper annular support fixedly connected to the open end of the liner body and a lower annular support fixed to the cartridge shell; an elastic pre-tightening element is sleeved between the upper and lower annular support seats; the elastic pre-tightening element provides axial pre-tightening force, ensuring that the spherical pairs always fit together, and realizing automatic return of the liner body to center under high temperature and micro-deformation.

[0006] The present invention is further configured such that: a first annular spherical body is fixed on the bottom surface of the upper annular support; and a first annular spherical seat adapted to the first annular spherical body is fixed on the surface of the lower annular support.

[0007] The invention is further configured such that: the double spherical self-centering coaxial support mechanism also includes a second annular spherical seat fixed on the inner wall of the perforator cartridge case; a second annular spherical body adapted to the second annular spherical seat is fixed on the outer wall of the shaped charge liner; the second annular spherical body and the second annular spherical seat, and the first annular spherical body and the first annular spherical seat form a double spherical pair, with the center of curvature coinciding with the axis of the shaped charge liner body.

[0008] The present invention is further configured such that: the first annular spherical body, the first annular spherical seat, the second annular spherical body, and the second annular spherical seat are all provided with a high-temperature resistant and wear-resistant coating on their peripheral surfaces; a bearing port is provided at the top of the medicine box shell; and a lower annular support seat is fixedly installed on the surface of the bearing port.

[0009] The invention is further configured such that: the elastic pretensioning component is a high-temperature alloy disc spring, which can withstand temperatures of not less than 300°C, providing axial pretensioning force to ensure that the spherical pair always fits together, does not melt or deform at high temperatures, and realizes automatic return of the shaped charge cover body.

[0010] The invention is further configured such that: the double spherical self-centering coaxial support mechanism also includes six rigid claws evenly distributed along the circumference; one end of the rigid claw is fixed with an arc contact head, forming a point contact support with the outer wall of the shaped charge liner, and the other end of the rigid claw is fixed on the inner wall of the perforator cartridge case.

[0011] The invention is further configured such that: a detonation groove is provided on the top of the perforator cartridge case; a detonation cord is embedded inside the detonation groove; a partition is provided inside the cartridge case; a fracturing charge is compressed between the cartridge case and the partition through a compression device; and a jet channel is reserved in the middle of the partition.

[0012] The invention is further configured such that: a plurality of guide ribs are symmetrically arranged on the inner wall of the jet channel; and a contraction calibration port is provided at the end of the jet channel to constrain the jet axially and calibrate its direction.

[0013] The present invention is further configured such that the guide ribs are at a helical angle of 10° to 30° with the axis, and the shrinkage angle of the shrinkage calibration port is 5° to 15°.

[0014] The advantages of this invention are: 1. This invention adopts a double spherical self-centering coaxial support mechanism. The curvature centers of the two sets of spherical pairs coincide with the axis of the propellant liner. With the continuous pre-tensioning of the high-temperature alloy disc spring, the propellant liner can automatically return to center under high temperature and micro-deformation, thus avoiding jet deflection from the source. It has high centering accuracy and simple and reliable structure.

[0015] 2. The present invention has six circumferentially distributed rigid claws that form point contact support on the outer wall of the propellant liner, resulting in uniform force distribution and no stress concentration. This ensures that the propellant liner remains perfectly round, without becoming elliptical, collapsing, or swaying during heating and explosive impact, and that the jet formation is highly symmetrical.

[0016] 3. This invention forms a stable axisymmetric vortex flow field by setting an axisymmetric spiral guide rib and a contraction calibration port in the jet channel. Even if the shaped charge liner body undergoes local slight deformation or the jet is slightly deflected, the jet can be forcibly pulled back to the axis through flow field constraint, thereby further improving the straightness and penetration stability of the jet. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the shaped charge liner structure of a high-temperature resistant shaped charge perforator according to the present invention.

[0018] Figure 2 For the present invention Figure 1 Enlarged view of region A.

[0019] Figure 3 This is a schematic diagram of the structure of the double-spherical self-centering coaxial support mechanism of the present invention.

[0020] Figure 4 This is a schematic diagram of the high-temperature resistant shaped charge perforator liner structure and the assembly of the perforator cartridge case and the cartridge case of the present invention.

[0021] Figure 5 This is a schematic diagram of the structure of the perforator cartridge case and the cartridge case assembly of the present invention.

[0022] In the figure: 1. Perforator cartridge case; 2. Molten charge liner assembly; 3. Molten charge liner body; 4. Double spherical self-centering coaxial support mechanism; 5. Upper annular support seat; 6. Breast cartridge shell; 7. Lower annular support seat; 8. Elastic preload; 9. First annular spherical body; 10. First annular spherical seat; 11. Second annular spherical seat; 12. Second annular spherical body; 13. Bearing port; 14. Rigid claw body; 15. Arc contact head; 16. Detonation groove; 17. Detonation cord; 18. Divider; 19. Fracturing cake; 20. Jet channel; 21. Guide rib. Detailed Implementation

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0025] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0026] Example 1, please refer to Figure 1-5 The present invention provides the following technical solutions: A high-temperature resistant shaped charge perforator liner structure, specifically, includes a liner assembly 2 that is spherically hinged to the inner wall of the perforator cartridge case 1; the liner assembly 2 includes a liner body 3 and a double-spherical self-centering coaxial support mechanism 4; the double-spherical self-centering coaxial support mechanism 4 includes an upper annular support seat 5 fixedly connected to the open end of the liner body 3 and a lower annular support seat 7 fixed to the cartridge case 6.

[0027] An elastic pretensioner 8 is fitted between the upper annular support 5 and the lower annular support 7. The elastic pretensioner 8 provides axial pretension force, so that the spherical pair always fits together, and the main body 3 of the drug-type cover 3 automatically returns to the center under high temperature and micro deformation. The elastic pretensioner 8 is in a slightly compressed state, continuously providing stable axial pretension force, ensuring that the double spherical pair fits together without gaps throughout the process, and eliminating radial movement caused by assembly and thermal deformation.

[0028] The bottom surface of the upper annular support 5 is fixed with a first annular spherical body 9; the surface of the lower annular support 7 is fixed with a first annular spherical seat 10 that is adapted to the first annular spherical body 9. The first annular spherical body 9 and the first annular spherical seat 10 have the same curvature and fit precisely to form a spherical pair. The center of curvature is completely coincident with the central axis of the drug-shaped cover body 3.

[0029] The double-spherical self-centering coaxial support mechanism 4 also includes a second annular spherical seat 11 fixed on the inner wall of the perforator cartridge case 1; a second annular spherical body 12 adapted to the second annular spherical seat 11 is fixed on the outer wall of the shaped charge liner body 3; the second annular spherical body 12 and the second annular spherical seat 11, the first annular spherical body 9 and the first annular spherical seat 10 form a double spherical pair, and the center of curvature coincides with the axis of the shaped charge liner body 3.

[0030] The first annular spherical body 9, the first annular spherical seat 10, the second annular spherical body 12, and the second annular spherical seat 11 are all provided with a high-temperature resistant and wear-resistant coating. The coating material is nickel-based alloy / tungsten carbide, with a thickness of 0.02 to 0.05 mm, which improves high-temperature sliding performance, reduces wear, and prevents seizing. A bearing port 13 is opened at the top inside the medicine box shell 6. The lower annular support 7 is fixedly installed on the surface of the bearing port 13. The bearing port 13 is a stepped positioning structure to ensure the coaxiality and installation strength of the lower annular support 7.

[0031] Working principle of this embodiment: In the long-term high-temperature environment of 150℃~250℃ underground, the shaped charge liner body 3 is prone to slight radial deformation, initial assembly misalignment, or slight eccentricity during use due to material thermal expansion and internal stress release. At this time, the double spherical pair composed of the upper second annular spherical body 12 and the second annular spherical seat 11, and the lower first annular spherical body 9 and the first annular spherical seat 10 can freely slide slightly around the curvature center that coincides with the axis of the shaped charge liner body 3 and adapt the angle, without rigid jamming.

[0032] The elastic preload 8, fitted between the upper annular support 5 and the lower annular support 7, remains in a slightly compressed state, continuously outputting a stable axial preload force. This forces the two sets of spherical pairs to fit tightly without gaps throughout the entire process, automatically eliminating radial movement and axial deviation caused by thermal deformation and assembly gaps. Driven by the preload force, the spherical pairs generate an adaptive reset torque, causing the shaped charge cover body 3 to quickly and accurately return to the central axis, achieving real-time automatic return to center under high-temperature micro-deformation.

[0033] With the high-temperature and wear-resistant coating on the double spherical sub-surface, it does not stick, wear, or jam during high-temperature sliding, thus preventing the shaped charge liner body from swaying or elliptical deformation at the source, ensuring symmetrical jet formation and no axis deviation, and stably guaranteeing the consistency of perforation accuracy and penetration depth.

[0034] Example 2, please refer to Figure 1-5 This embodiment two is an improvement on the first embodiment. This embodiment is optimized for ultra-high temperature deep wells of 250℃~300℃, and enhances high temperature stability and anti-deformation ability. A new circumferential rigid stable structure is added. Specifically, the elastic pretensioning component 8 adopts a high temperature alloy disc spring, which can withstand high temperature of not less than 300℃ and can withstand 350℃ for a short time. The disc spring group adopts a mating combination design, which has stable pretension force and small creep. It does not soften, fail or permanently deform at high temperature, and continuously ensures the spherical pair fit. It does not melt or deform at high temperature, and realizes the automatic return of the shaped charge cover body 3.

[0035] The double-spherical self-centering coaxial support mechanism 4 also includes six rigid claws 14 evenly distributed along the circumference, with adjacent rigid claws 14 having an included angle of 60°, and the force is completely symmetrical; one end of the rigid claw 14 is fixed with an arc-shaped contact head 15, which forms a point contact support with the outer wall of the shaped charge liner body 3. The contact area is small, there is no stress concentration, and it does not hinder the centering action. The six-point support forms a ring constraint ring, which forces the shaped charge liner body 3 to maintain a perfect circular shape, preventing high-temperature softening and collapse, ellipticization, and radial bulging. The other end of the rigid claw 14 is fixed to the inner wall of the perforator cartridge case 1. The arc-shaped contact head 15 and the outer wall of the shaped charge liner body 3 are reserved with a high-temperature expansion gap of 0.05 to 0.1 mm, which not only ensures the support effect but also avoids thermal expansion jamming.

[0036] Working principle of this embodiment two: In ultra-high temperature deep well conditions of 250℃~300℃, ordinary elastic elements are prone to softening and failure. In this embodiment, a high temperature alloy disc spring is used as the elastic preload element 8. It can work for a long time at 300℃ and withstand short-term high temperature at 350℃ without creeping, melting, or permanent deformation. It can continuously and stably output axial preload force, ensuring that the double spherical pair is always tightly fitted and maintaining reliable automatic return capability at high temperature.

[0037] Meanwhile, six circumferentially distributed rigid claws 14 form a 360° uniform radial support ring, and the end arc contact head 15 makes flexible point contact with the outer wall of the shaped charge body 3. This not only does not restrict the adaptive self-aligning action of the double spherical pair, but also applies balanced radial constraint to the outer wall of the shaped charge body, avoiding defects such as mouth edge collapse, overall ellipticization, and radial bulging caused by material softening at high temperatures.

[0038] The double-spherical self-centering coaxial support mechanism 4 is responsible for precise axis calibration, while the circumferential rigid claw body 14 is responsible for maintaining the perfect circle shape. The two form a dual guarantee system of "centering + shape preservation". Under the combined action of high temperature thermal deformation and explosive impact load, the shaped charge liner body 3 can still maintain an ideal symmetrical shape, completely avoiding problems such as jet deflection, gun rubbing, and reduced perforation efficiency, and greatly improving the working stability and reliability of the perforator in ultra-high temperature environments.

[0039] Example 3, please refer to Figure 1-5 This third embodiment is an improvement on the first embodiment as follows: Specifically, the top of the perforator cartridge case 1 is provided with a detonation groove 16; a detonation cord 17 is embedded inside the detonation groove 16, and the detonation cord 17 is evenly arranged around the circumference to achieve synchronous detonation around the circumference, ensuring that the explosive energy acts evenly and symmetrically on the shaped charge body 3; a partition 18 is provided inside the explosive box shell 6, and a charging cavity is formed between the partition 18 and the explosive box shell 6, and the fracturing cake 19 is compacted and filled by a hydraulic compression device, so that the charging density is uniform and the energy output is stable; the partition 18 plays the role of energy separation, fracturing first and then perforation, avoiding mutual interference; a jet channel 20 is reserved in the middle of the partition 18, and the jet channel 20 is mirror polished to reduce jet friction loss.

[0040] The inner wall of the jet channel 20 is symmetrically provided with several guide ribs 21; the end of the jet channel 20 is provided with a contraction calibration port for axial constraint and directional calibration of the jet. The height of the guide ribs 21 is 1 / 10 to 1 / 8 of the channel diameter, and the number is 6 to 8, which are symmetrically distributed. The length of the contraction calibration port is 1.5 to 2 times the channel diameter to ensure the calibration effect.

[0041] The guide rib 21 has a helical angle of 10° to 30° with the axis, preferably 20°, to form a stable axisymmetric vortex flow field; the contraction angle of the contraction calibration port is 5° to 15°, preferably 10°, to axially constrain, directionally calibrate, and enhance the energy concentration of the jet.

[0042] Working principle of this embodiment three: The detonating cord 17 is evenly arranged circumferentially to achieve synchronous detonation throughout the circumference, ensuring that the explosive energy acts symmetrically and evenly on the shaped charge liner 3 and the fracturing cake 19, avoiding uneven stress on the shaped charge liner 3 due to energy eccentricity. After detonation, the fracturing cake 19 is detonated first, generating high-pressure gas to pre-fracture the formation, forming an initial fracture network and creating favorable conditions for subsequent jet guidance; the baffle 18 separates the fracturing energy and perforation energy in sequence, ensuring that they do not interfere with each other, and ensuring a stable and controllable operation sequence.

[0043] The explosive energy drives the shaped charge liner body 3 to converge axially, forming a high-speed metal jet that enters the jet channel 20. The axisymmetric spiral guide ribs 21 on the inner wall of the jet channel 20 guide the jet with a spiral angle of 10° to 30° to form a stable axisymmetric vortex flow field, and perform preliminary centering correction on the jet that is slightly deflected due to local melting at high temperature, thus eliminating the asymmetric disturbance of the jet.

[0044] The jet continues to advance to the contraction calibration port, where it is axially tightened, directionally calibrated, and energy-focused under the constraint of a contraction angle of 5° to 15°. This forces the jet, which has deviated from the axis, back to the center, further improving the straightness and penetration depth of the jet.

[0045] Even if the shaped charge liner body 3 experiences localized minor melting or slight deformation at high temperatures, the eddy current field constraint and conical orifice geometry calibration can still stably pull the jet back to the axis, ultimately achieving efficient integrated perforation-fracturing operation at high temperatures, significantly improving orifice formation quality, penetration depth stability, and oil and gas flow conduction capacity.

[0046] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0047] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0048] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0050] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A high-temperature resistant shaped charge liner structure for a shaped charge perforator, characterized in that: It includes a shaped charge liner assembly (2) that is spherically hinged to the inner wall of the perforator cartridge case (1); the shaped charge liner assembly (2) includes a shaped charge liner body (3) and a double spherical self-centering coaxial support mechanism (4); The double-spherical self-centering coaxial support mechanism (4) includes an upper annular support seat (5) fixedly connected to the opening end of the medicine liner body (3) and a lower annular support seat (7) fixed on the medicine box shell (6); an elastic pre-tightening member (8) is sleeved between the upper annular support seat (5) and the lower annular support seat (7). The elastic preload (8) provides axial preload force, so that the spherical pair always fits, and the main body (3) of the drug-type cover automatically returns to center under high temperature and micro deformation. The bottom surface of the upper annular support (5) is fixed with a first annular spherical body (9); the surface of the lower annular support (7) is fixed with a first annular spherical seat (10) that is adapted to the first annular spherical body (9). The double spherical self-centering coaxial support mechanism (4) also includes a second annular spherical seat (11) fixed on the inner wall of the perforator cartridge case (1); a second annular spherical body (12) adapted to the second annular spherical seat (11) is fixed on the outer wall of the shaped charge body (3); the second annular spherical body (12) and the second annular spherical seat (11), and the first annular spherical body (9) and the first annular spherical seat (10) form a double spherical pair, with the center of curvature coinciding with the axis of the shaped charge body (3).

2. The high-temperature resistant shaped charge liner structure for a shaped charge perforator according to claim 1, characterized in that: The first annular spherical body (9), the first annular spherical seat (10), the second annular spherical body (12) and the second annular spherical seat (11) are all provided with a high temperature and wear-resistant coating on their periphery; a bearing port (13) is opened at the top inside the medicine box shell (6); the lower annular support seat (7) is fixedly installed on the surface of the bearing port (13).

3. The high-temperature resistant shaped charge liner structure for a shaped charge perforator according to claim 1, characterized in that: The elastic preload (8) is made of high-temperature alloy disc spring.

4. The high-temperature resistant shaped charge liner structure for a shaped charge perforator according to claim 1, characterized in that: The double spherical self-centering coaxial support mechanism (4) also includes six rigid claws (14) evenly distributed along the circumference; one end of the rigid claw (14) is fixed with an arc contact head (15) to form a point contact support with the outer wall of the shaped charge body (3), and the other end of the rigid claw (14) is fixed on the inner wall of the perforator cartridge case (1).

5. The high-temperature resistant shaped charge liner structure for a shaped charge perforator according to claim 1, characterized in that: The top of the perforator cartridge case (1) is provided with an initiation groove (16); the initiation groove (16) is inlaid with an initiation cord (17); the cartridge case (6) is provided with a partition (18); a fracturing cake (19) is compressed between the cartridge case (6) and the partition (18) through a compression device; a jet channel (20) is reserved in the middle of the partition (18).

6. The high-temperature resistant shaped charge liner structure for a shaped charge perforator according to claim 5, characterized in that: The inner wall of the jet channel (20) is symmetrically provided with several guide ribs (21); the end of the jet channel (20) is provided with a contraction calibration port for axial constraint and directional calibration of the jet.

7. The high-temperature resistant shaped charge liner structure for a shaped charge perforator according to claim 6, characterized in that: The guide rib (21) has a spiral angle of 10° to 30° with the axis, and the shrinkage angle of the shrinkage calibration port is 5° to 15°.

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