An ultrahigh-temperature deep-penetration shaped charge and a preparation method thereof

Abstract

This invention belongs to the technical field of perforating projectiles for oil and gas wells, specifically relating to an ultra-high temperature deep-penetrating perforating projectile and its preparation method. The perforating projectile includes a casing, PYX initiating explosive, PYX-based main explosive, and a high-tungsten powder shaped charge liner. The high-tungsten powder shaped charge liner is placed inside the cavity of the casing, and the PYX-based main explosive is filled in the area formed by the high-tungsten powder shaped charge liner and the inner wall of the casing. The inner cavity of the casing is composed of a cylindrical section, a first conical section, a second conical section, an arc section, and a third conical section connected in sequence. The high-tungsten powder shaped charge liner, by mass percentage, comprises 80%-85% tungsten powder, 10%-15% copper powder, and other auxiliary materials. The use of high tungsten powder improves penetration performance, enhances stability, improves forming performance, and increases wear resistance. The conical-arc structure designed for the inner cavity of the casing helps to improve the energy utilization rate of the explosive, thereby increasing the penetration depth.

Description

Technical Field

[0001] This invention belongs to the field of perforation projectile technology for oil and gas wells, specifically relating to an ultra-high temperature deep-penetrating perforation projectile and its preparation method. Background Technology

[0002] In recent years, with the increasing efforts in deep and ultra-deep oil and gas exploration and development on land, the depth of oil and gas wells has been continuously broken, and the temperature of the formation at the bottom of the well has increased. As the most important completion method for ultra-deep wells, perforation is crucial to oil and gas exploration and development. During the perforation completion process of ultra-deep wells, the perforator will be subjected to the high temperature and high pressure environment of the wellbore, which will seriously affect its perforation performance and even lead to failure.

[0003] A search revealed that patent document CN111119803A discloses a shaped charge liner for a large-aperture deep-penetrating projectile and its preparation method. The shaped charge liner's composition includes 10%-35% tungsten powder and 30%-45% electrolytic copper powder. This addresses the problem that existing shaped charge liners cannot release a large amount of heat energy, relying solely on high-speed metal flow impacting the target to form the channel, thus requiring complex shaped charge liner structures to achieve the desired jet quality and velocity distribution. However, its low tungsten powder content results in low penetration performance for the perforating projectile. The accompanying drawings also show the overall structure of the perforating projectile, but without specific details. The drawings reveal a conical design within the cartridge case; however, the presence of a single conical structure cannot effectively control the extension of the metal jet, potentially leading to jet overlap and breakage, thus affecting the projectile's penetration depth.

[0004] Existing ultra-high temperature perforation systems primarily use HNS matrix explosives, with a maximum temperature resistance of 210℃ / 170h. Under extreme conditions, downhole ultra-high temperature perforation equipment is prone to spontaneous combustion, leading to complex downhole situations such as perforation gun expansion and jamming. The higher the bottom hole temperature and the longer the residence time, the faster the explosive decomposes, which greatly reduces the perforation performance of the perforation projectile in real formations.

[0005] In summary, the existing technology has the following drawbacks: 1) The temperature resistance of the perforating projectile is insufficient and cannot meet the application requirements of 260℃ / 72h; 2) The ultra-high temperature perforating projectile is limited by the detonation velocity and heat of the explosive, resulting in a low penetration depth of the perforating projectile into the concrete target. Summary of the Invention

[0006] The purpose of this invention is to provide an ultra-high temperature deep-penetrating perforating projectile and its preparation method, which solves the problems of insufficient temperature resistance and low perforation depth of existing perforating projectiles.

[0007] This invention is achieved through the following technical solution: This invention discloses an ultra-high temperature deep-penetrating projectile, comprising a projectile casing, a PYX initiator, a PYX-based main explosive, and a high-tungsten powder shaped charge liner; A high-tungsten powder shaped charge liner is placed in the inner cavity of the cartridge case, and the PYX-based main explosive is filled in the area formed by the high-tungsten powder shaped charge liner and the inner wall of the cartridge case; The inner cavity of the cartridge case is composed of a cylindrical section, a first conical section, a second conical section, an arc section, and a third conical section connected in sequence. By mass percentage, the raw materials for high-tungsten powder shaped charges include 80%-85% tungsten powder, 10%-15% copper powder, and other auxiliary materials.

[0008] Furthermore, the cone angle of the first cone segment ranges from 10° to 12°, the cone angle of the second cone segment ranges from 18° to 24°, and the cone angle of the third cone segment ranges from 50° to 60°. The radius of the third arc segment ranges from 4 to 5 mm.

[0009] Furthermore, the PYX-based main explosive is formed by mixing and granulating PYX-based explosive molding powder and graphite.

[0010] Furthermore, the cartridge case is made of alloy steel, and the yield strength of the cartridge case reaches more than 1600 MPa.

[0011] Furthermore, the high-tungsten powder liner is composed of a first arc-shaped segment, a conical segment A, a conical segment B, and a second arc-shaped segment connected in sequence.

[0012] Furthermore, the radius of the first arc segment ranges from 2 to 6 mm; The cone angle of cone segment A ranges from 40° to 44°, and the cone angle of cone segment B ranges from 44° to 48°. The radius of the second arc segment ranges from 50 to 100 mm.

[0013] Furthermore, both the first and second arc-shaped segments have variable wall thickness structures, ranging from 1 to 4 mm.

[0014] Furthermore, the ultra-high temperature deep-penetrating bullet has a perforation depth of 852-890mm and a temperature resistance of 260℃.

[0015] This invention also discloses a method for preparing the ultra-high temperature deep-penetrating projectile, comprising the following steps: S1. Preparation of the drug-formation liner: S1.1, Mixing powder The mixture of 80%-85% tungsten powder, 10%-15% copper powder, and other auxiliary materials is ball-milled under argon protection to obtain a uniform mixed powder. S1.2, Press the mixed powder; S1.3 The pressed-formed shaped charge liner is sintered using a vacuum reduction sintering process to obtain a high-tungsten powder shaped charge liner; S2. Load the PYX detonator into the detonation hole of the cartridge case, and at the same time, according to the type of perforated cartridge, evenly cover the PYX base explosive on the detonator and load it into the inner cavity of the cartridge case. S3. Apply adhesive evenly to the outer surface of the shaped charge liner and place it on the PYX-based main explosive. Pressing is performed at a pressure of not less than 18 MPa; S4. After pressing, apply sealing glue evenly to the connection between the cartridge case, PYX-based main explosive and high-tungsten powder shaped charge, and seal with the sealing glue.

[0016] Furthermore, S1.3 specifically involves heating at a rate of 10–12 °C / min, holding at 1100 °C for 1 hour, then cooling at a rate of 5 °C / min, holding at 350 °C for 1 hour, and then cooling down to room temperature with the furnace.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: This invention discloses an ultra-high temperature deep-penetrating perforating projectile, comprising a cartridge case, a PYX initiating explosive, a PYX-based main explosive, and a high-tungsten powder liner. The invention also optimizes the formulation of the liner, which is made of 80%-85% tungsten powder and 10%-15% copper powder. The high tungsten powder content enhances penetration performance, stability, formability, and abrasion resistance. Under the explosive's detonation, the powder-based liner transforms back into powder, becoming a metal jet. This jet is propelled by the explosive to penetrate the casing, penetrate the formation, and ultimately form a perforation channel, improving the projectile's penetration performance. The continuous and stable jet formed after launch further enhances the projectile's penetration depth. The use of high-temperature-resistant PYX initiating explosive and PYX-based main explosive allows for a maximum temperature resistance of up to 260℃. This invention is mainly designed for the cartridge case. The inner cavity of the cartridge case is designed with a conical arc structure, which is beneficial to improving the energy utilization rate of the explosive and thus increasing the penetration depth.

[0018] Furthermore, this invention employs PYX initiating explosive, which possesses strong initiation capability. Upon receiving a corresponding initiation signal, it rapidly generates sufficiently powerful detonation energy to reliably detonate the main charge in the perforating projectile. Even under complex downhole pressure and temperature conditions, it can stably output sufficient energy, ensuring the perforating projectile detonates as expected and performs its perforation function. This allows the perforating projectile to efficiently form effective perforation channels in oil and gas well casings, cement sheaths, and surrounding rock formations, providing a good flow path for subsequent oil and gas extraction.

[0019] Furthermore, this invention incorporates a double-cone, double-arc structure for the explosive liner, which improves the energy utilization rate of the explosive and thus increases the penetration depth. The synergistic effect of the entire double-cone, double-arc structure, from jet formation to efficient energy utilization, ultimately contributes to increased penetration depth. A stable and continuous jet can more effectively concentrate energy, penetrating the target with less energy dispersion. Simultaneously, rational energy utilization allows the jet to maintain high velocity and energy, continuously penetrating the target. Moreover, the appropriate expansion of the jet's coverage area helps overcome problems such as the inhomogeneity of the target material during penetration, making the penetration process more stable and deeper, thereby achieving better penetration results. Attached Figure Description

[0020] Figure 1 Schematic diagram of an ultra-high temperature deep-penetrating projectile; Figure 2 This is a schematic diagram of the cross-sectional structure of the cartridge case; Figure 3 This is a schematic diagram of the structure of a high-tungsten powder liner.

[0021] In the image: 1. PYX detonator; 2. Cartridge casing; 3. PYX-based main explosive; 4. High-tungsten powder shaped charge liner; 5. Sealing adhesive; 21. Cylindrical section; 22. Conical section; 23. Detonation hole; 24. Cylindrical section; 25. First conical section; 26. Second conical section; 27. Arc section; 28. Third conical section; 41. First arc segment; 42. Conical segment A; 43. Conical segment B; 44. Second arc segment. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the present invention clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of the present invention, and not all of them.

[0023] The detailed description of the embodiments of the present invention provided in the following figures is not intended to limit the scope of the claimed invention, but merely to illustrate one selected embodiment of the invention. All other embodiments obtained by those skilled in the art based on the figures and embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] It should be noted that the terms “comprising,” “including,” or any other variations are intended to cover non-exclusive inclusion, such that a process, element, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to the process, element, method, article, or apparatus.

[0025] like Figure 1 As shown, this invention discloses an ultra-high temperature deep-penetrating projectile, comprising a cartridge case 2, a PYX initiating charge 1, a PYX-based main explosive 3, and a high-tungsten powder shaped charge liner 4. The high-tungsten powder shaped charge liner 4 is placed in the inner cavity of the cartridge case 2, and the PYX-based main explosive 3 is filled in the area formed by the high-tungsten powder shaped charge liner 4 and the inner wall of the cartridge case 2.

[0026] Sealing adhesive 5 is evenly applied at the connection between the perforated projectile casing 2, the PYX-based main explosive 3, and the high-tungsten powder shaped charge liner 4 to achieve a sealing effect.

[0027] The sealing adhesive 5 is a mature ultra-high temperature industrial adhesive.

[0028] like Figure 2 As shown, the cartridge case 2 includes a cylindrical section 21 and a conical section 22. An initiation hole 23 is pre-formed at the front end face of the conical section 22, and the PYX initiating explosive 1 is filled into the initiation hole 23.

[0029] Specifically, the cartridge case 2 is made of high-strength alloy steel with a yield strength of 1600 MPa or higher, which can effectively improve the energy reflectivity of the explosive. The interior of the cartridge case consists of multiple conical structures. By controlling the jet shape after the explosive detonation through different cone angle sequences, the jet stacking and breakage are avoided, which is beneficial to improving the penetration performance of the perforating projectile. The cone angles consist of different series of cone angles ranging from 10° to 60°.

[0030] Specifically, such as Figure 2 As shown, the inner cavity of the cartridge case 2 is composed of a cylindrical segment 24, a first conical segment 25, a second conical segment 26, an arc segment 27, and a third conical segment 28 connected in sequence. The cone angle of the first conical segment 25 is in the range of 10° to 12°, the cone angle of the second conical segment 26 is in the range of 18° to 24°, the radius of the arc segment 27 is in the range of 4-5 mm, and the cone angle of the third conical segment 28 is in the range of 50° to 60°.

[0031] Even better, such as Figure 3As shown, the high-tungsten powder shaped charge liner 4 is designed with a double-cone, double-arc structure, consisting of a first arc segment 41, a cone segment A 42, a cone segment B 43, and a second arc segment 44. Specifically, the radius of the first arc segment 41 ranges from 2 to 6 mm, and the wall thickness is a variable wall thickness structure ranging from 1 to 4 mm; the cone angle of cone segment A 42 ranges from 40° to 44°, the cone angle of cone segment B 43 ranges from 44° to 48°, and the radius of the second arc segment 44 ranges from 50 to 100 mm, with a variable wall thickness ranging from 1 to 4 mm. This design improves the energy utilization rate of the explosive, thereby increasing the penetration depth.

[0032] The specific functions of the bipyramidal structure are as follows: The different cone angles of cone sections A 42 and B 43 allow the liner to gradually and orderly form a jet under the drive of the explosive energy. In the initial stage of the explosion, the smaller cone angle of cone section A 42 makes it easier to compress and accelerate the liner material, initially forming the leading part of the jet. As the explosive energy continues to transfer, cone section B 43, with a slightly larger cone angle, further pushes the liner material, allowing the latter half of the jet to catch up with the leading part at a suitable speed and shape, thus forming a continuous, stable jet with a good velocity gradient. This continuous and stable jet can more effectively transfer energy when penetrating the target, reducing jet dispersion and energy loss.

[0033] The specific functions of the double-arc structure are as follows: The radius of the first arc segment 41 ranges from 2 to 6 mm, and the radius of the second arc segment 44 ranges from 50 to 100 mm. The first arc segment 41, being closer to the detonation point of the explosive, has a smaller radius that allows the liner to respond quickly in the early stages of the explosion, effectively focusing and converting the explosive energy into the kinetic energy of the liner material. The larger radius of the second arc segment 42, in the later stages of jet formation, guides and expands the jet. It allows the jet to maintain a certain velocity and density while appropriately expanding its coverage area, thus enabling it to penetrate a larger area and improving penetration stability.

[0034] The function of variable wall thickness structures is as follows: The first arc segment 41 and the second arc segment 42 have variable wall thickness structures, ranging from 1 to 4 mm. This variable wall thickness design allows for the rational allocation of material based on the role of different positions of the liner in the jet formation process. Near the detonation point, the wall thickness can be relatively thicker to withstand greater explosive impact, effectively transferring explosive energy to the liner material and preventing premature rupture. Conversely, away from the detonation point, the wall thickness can be appropriately thinner, allowing the liner material to be more easily compressed and accelerated when driven to form the jet, reducing energy loss during the liner's own deformation. Through this rational wall thickness variation, more explosive energy can be used to form a high-quality jet, rather than being wasted on ineffective deformation or rupture of the liner, thereby improving explosive energy.

[0035] Specifically, the PYX detonator 1 is composed of high-purity PYX and is used to receive the detonation impact energy of the detonating cord and detonate the PYX-based main explosive 3 in the perforating projectile.

[0036] The PYX-based main explosive 3 is formed by mixing and granulating PYX-based explosive molding powder, graphite, etc., and the PYX-based explosive molding powder passes through a 10-mesh sieve.

[0037] The high-tungsten powder shaped charge liner 4 is mainly composed of a mixture of tungsten powder and copper powder, wherein the tungsten powder content is 80%-85%, the copper powder content is 10%-15%, and other auxiliary materials are 3%-5%.

[0038] Specifically, other auxiliary materials include 0.5%-1% bismuth powder, 1.5%-1.8% lead powder, 0.3%-0.5% aluminum powder, 0.4%-1.0% iron powder, and 0.3%-0.7% zinc powder.

[0039] This invention also includes a redesigned formulation for the shaped charge liner, employing a high content of tungsten powder to enhance penetration performance, stability, formability, and wear resistance. Under the explosive force of the charge, the powder-based shaped charge liner transforms back into powder, a process known as a metal jet. This jet, propelled by the explosive, penetrates the casing, penetrates the formation, and ultimately forms a perforation channel. Specific advantages include: When tungsten powder and copper powder are mixed in a certain proportion, the good ductility of copper powder can compensate for the brittleness of tungsten powder, giving the liner high strength while also possessing a certain degree of flexibility, making it less prone to cracking or breakage. This synergistic effect helps improve the impact resistance and durability of the liner, enabling it to form a stable and continuous metal jet after the explosive detonates.

[0040] Because of the high density of tungsten powder, the jet density formed by the shaped charge after the explosive detonation is correspondingly increased. According to the theory of penetrating fluid dynamics, the greater the jet density, the stronger its penetration capability. When it is fired at the target, it can more effectively penetrate obstacles such as rocks and metals, thereby increasing the penetration depth and aperture of the perforating projectile and better meeting the engineering needs of oil and gas extraction and other projects.

[0041] Because tungsten powder has a high velocity of sound, it helps to increase the head velocity of the jet. Increased jet head velocity allows the jet to have greater kinetic energy and impact force during penetration, further enhancing its destructive capability against the target, enabling it to penetrate the target object more quickly and improving perforation efficiency.

[0042] Because tungsten has an extremely high melting point, the metal powder is less prone to deformation or melting under the high temperatures generated by explosive detonation. This makes the jet more stable during formation and movement, enabling it to be more accurately aimed at the target, reducing jet divergence caused by melting metal powder, and improving the accuracy and effectiveness of the perforation.

[0043] Compared to some other metals, tungsten is chemically relatively stable and is less prone to unnecessary chemical reactions with other substances in the complex chemical environment of explosive detonations. This helps maintain the performance stability of metal powder materials, ensuring that they can form the ideal jet as designed at the moment of explosion, thus improving the reliability and consistency of perforating projectiles. Traditional perforating projectiles have a higher copper powder content than tungsten powder, resulting in insufficient penetration performance.

[0044] Furthermore, tungsten has high hardness, which allows the metal jet to better resist wear and corrosion when it comes into contact with the target object during perforation. Especially when facing hard targets, the high-tungsten-content liner can maintain good jet performance and perforation effect, thereby improving the single-well productivity of oil and gas wells.

[0045] This invention discloses a method for preparing an ultra-high temperature deep-penetrating projectile, comprising a pressure shield, a propellant charge, and a projectile pressing mechanism. The specific steps are as follows: S1. Preparation of drug-formed liner The shaped charge is made using a vacuum reduction sintering process, which includes powder mixing, pressing, and sintering.

[0046] 1.1 Mixing powder Tungsten powder (80%-85%), copper powder (10%-15%), and other auxiliary materials are placed together with steel balls in a stainless steel container and ball-milled in a vibrating high-energy ball mill for at least 3 hours, with argon gas protection, to obtain a uniform mixed powder.

[0047] Other auxiliary materials include 0.5%-1% bismuth powder, 1.5%-1.8% lead powder, 0.3%-0.5% aluminum powder, 0.4%-1.0% iron powder, and 0.3%-0.7% zinc powder.

[0048] 1.2 Suppression To ensure that the pressed tungsten-copper powder liner has a uniform density distribution and stable performance, a spinning press is selected for spin molding.

[0049] 1.3 Sintering The pressed molten liner was then sintered in a vacuum sintering furnace: the temperature was increased at a rate of 10℃ / min, held at 1100℃ for 1 hour, then decreased at a rate of 5℃ / min, held at 350℃ for 1 hour, and then cooled to room temperature in the furnace.

[0050] Finally, a molding inspection is conducted, specifically checking the dimensions, appearance, and cracks of the shaped charge cover.

[0051] S2. After the shield is pressed, 1g-2g of PYX detonator 1 is loaded into the detonation hole 23 of the cartridge case 2. At the same time, according to the type of perforated cartridge, 15g-45g of PYX base explosive 3 is evenly covered on the detonator and loaded into the inner cavity of the cartridge case.

[0052] The PYX initiating explosive 1 is composed of high-purity PYX and is used to receive the detonation impact energy of the detonating cord and detonate the PYX-based main explosive 3 of the perforating projectile.

[0053] The PYX-based main explosive 3 is formed by mixing and granulating PYX-based explosive molding powder, graphite, etc., and the PYX-based explosive molding powder passes through a 10-mesh sieve.

[0054] The cartridge case 2 is made of high-strength alloy steel with a yield strength of 1600 MPa or higher.

[0055] S3. Apply adhesive evenly to the outer surface of the shaped charge liner and place it on the PYX-based main explosive 3. Press it on a hydraulic press using a perforation mold, with a pressing pressure of not less than 18 MPa.

[0056] S4. After pressing, apply sealing adhesive 5 evenly to the connection between the cartridge case 2, PYX-based main explosive 3 and high-tungsten powder shaped charge 4, and seal with sealing adhesive 5.

[0057] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0058] Example 1 The present invention discloses a method for preparing an ultra-high temperature deep-penetrating projectile, the specific steps of which are as follows: S1. Preparation of drug-formed liner 1.1 Mixing powder By mass percentage, 85% tungsten powder, 12% copper powder, 0.5% bismuth powder, 1.5% lead powder, 0.3% aluminum powder, 0.4% iron powder, and 0.3% zinc powder are mixed and then placed in a stainless steel container with steel balls. The mixture is then ball-milled in a vibrating high-energy ball mill for 4 hours under argon protection to obtain a uniform mixed powder.

[0059] 1.2 Suppression A spinning press is used to spin-press the shaped liner to obtain a pressed liner. Spin-pressed liners are of higher quality, with better pressing uniformity and wall thickness uniformity.

[0060] 1.3 Sintering The pressed molten liner is then sintered: the temperature is increased at a rate of 10℃ / min, held at 1100℃ for 1 hour, then cooled at a rate of 5℃ / min, held at 350℃ for 1 hour, and then cooled to room temperature in the furnace.

[0061] S2. After the shield is pressed, 1g of PYX detonator 1 is placed in the detonation hole 23 of the cartridge case 2. At the same time, according to the type of perforated cartridge, 15g of PYX base explosive 3 is evenly covered on the detonator and placed into the inner cavity of the cartridge case.

[0062] The PYX-based main explosive 3 is formed by mixing and granulating PYX-based explosive molding powder, graphite, etc., and the PYX-based explosive molding powder passes through a 10-mesh sieve.

[0063] S3. Apply adhesive evenly to the outer surface of the high-tungsten powder shaped charge liner 4 and place it on the PYX-based main explosive 3. Press it on a hydraulic press using a perforation mold, with a pressing pressure of not less than 18 MPa.

[0064] S4. After pressing, apply sealing adhesive 5 evenly to the connection between the cartridge case 2, PYX-based main explosive 3 and high-tungsten powder shaped charge 4, and seal with sealing adhesive 5.

[0065] Example 2 The present invention discloses a method for preparing an ultra-high temperature deep-penetrating projectile, the specific steps of which are as follows: S1. Preparation of drug-formed liner 1.1 Mixing powder By mass percentage, 80% tungsten powder, 15% copper powder, 1% bismuth powder, 1.8% lead powder, 0.5% aluminum powder, 1.0% iron powder, and 0.7% zinc powder are mixed and then placed in a stainless steel container with steel balls. The mixture is then ball-milled in a vibrating high-energy ball mill for 5 hours under argon protection to obtain a uniform mixed powder.

[0066] 1.2 Suppression A spinning press is used to spin press the shaped medicament to obtain the pressed medicament cover.

[0067] 1.3 Sintering The pressed molten liner is then sintered: the temperature is increased at a rate of 11℃ / min, held at 1100℃ for 1 hour, then cooled at a rate of 5℃ / min, held at 350℃ for 1 hour, and then cooled to room temperature in the furnace.

[0068] S2. After the shield is pressed, 2g of PYX detonator 1 is placed in the detonation hole 23 of the cartridge case 2. At the same time, according to the type of perforated cartridge, 30g of PYX base explosive 3 is evenly covered on the detonator and placed into the inner cavity of the cartridge case.

[0069] The PYX-based main explosive 3 is formed by mixing and granulating PYX-based explosive molding powder, graphite, etc., and the PYX-based explosive molding powder passes through a 10-mesh sieve.

[0070] S3. Apply adhesive evenly to the outer surface of the high-tungsten powder shaped charge liner 4 and place it on the PYX-based main explosive 3. Press it on a hydraulic press using a perforation mold, with a pressing pressure of not less than 18 MPa.

[0071] S4. After pressing, apply sealing adhesive 5 evenly to the connection between the cartridge case 2, PYX-based main explosive 3 and high-tungsten powder shaped charge 4, and seal with sealing adhesive 5.

[0072] Example 3 The present invention discloses a method for preparing an ultra-high temperature deep-penetrating projectile, the specific steps of which are as follows: S1. Preparation of drug-formed liner 1.1 Mixing powder By mass percentage, 83% tungsten powder, 13% copper powder, 0.8% bismuth powder, 1.6% lead powder, 0.4% aluminum powder, 0.7% iron powder, and 0.5% zinc powder are mixed and then placed in a stainless steel container with steel balls. The mixture is then ball-milled in a vibrating high-energy ball mill for 4 hours under argon protection to obtain a uniform mixed powder.

[0073] 1.2 Suppression A spinning press is used to spin press the shaped medicament to obtain the pressed medicament cover.

[0074] 1.3 Sintering The pressed molten liner is then sintered: the temperature is increased at a rate of 12℃ / min, held at 1100℃ for 1 hour, then cooled at a rate of 5℃ / min, held at 350℃ for 1 hour, and then cooled to room temperature in the furnace.

[0075] S2. After the shield is pressed, 2g of PYX detonator 1 is placed in the detonation hole 23 of the cartridge case 2. At the same time, according to the type of perforated cartridge, 45g of PYX base explosive 3 is evenly covered on the detonator and placed into the inner cavity of the cartridge case.

[0076] The PYX-based main explosive 3 is formed by mixing and granulating PYX-based explosive molding powder, graphite, etc., and the PYX-based explosive molding powder passes through a 10-mesh sieve.

[0077] S3. Apply adhesive evenly to the outer surface of the high-tungsten powder shaped charge liner 4 and place it on the PYX-based main explosive 3. Press it on a hydraulic press using a perforation mold, with a pressing pressure of not less than 18 MPa.

[0078] S4. After pressing, apply sealing adhesive 5 evenly to the connection between the cartridge case 2, PYX-based main explosive 3 and high-tungsten powder shaped charge 4, and seal with sealing adhesive 5.

[0079] The perforating projectiles prepared in Examples 1-3 were loaded into the same perforating gun and subjected to perforation tests on concrete targets under ground conditions. The perforation depth data and temperature resistance of the perforating projectiles are shown in the table below.

[0080]

[0081] In some special deep geothermal wells or ultra-deep wells, perforating projectiles may face ultra-high temperature environments. Generally, temperatures of 200℃ or higher are considered ultra-high temperature environments. As shown in the table above, the ultra-high temperature deep-penetrating perforating projectile prepared in this invention can achieve a perforation depth of 852-890mm and a temperature resistance of 260℃, making it suitable for use in ultra-high temperature environments.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A high-temperature deep-penetration projectile, characterized in that, Includes cartridge case (2), PYX detonator (1), PYX-based main explosive (3), and high-tungsten powder shaped charge liner (4); The high-tungsten powder shaped charge liner (4) is placed in the inner cavity of the cartridge case (2), and the PYX-based main explosive (3) is filled in the area formed by the high-tungsten powder shaped charge liner (4) and the inner wall of the cartridge case (2); The inner cavity of the cartridge case (2) is composed of a cylindrical section (24), a first conical section (25), a second conical section (26), an arc section (27), and a third conical section (28) connected in sequence; By mass percentage, the raw materials of the high tungsten powder liner (4) include 80%-85% tungsten powder, 10%-15% copper powder, and other auxiliary materials.

2. The ultra-high temperature deep-penetrating projectile according to claim 1, characterized in that, The cone angle of the first cone segment (25) ranges from 10° to 12°, the cone angle of the second cone segment (26) ranges from 18° to 24°, and the cone angle of the third cone segment (28) ranges from 50° to 60°. The radius of the third arc segment (27) is 4-5 mm.

3. The ultra-high temperature deep-penetrating projectile according to claim 1, characterized in that, The PYX-based main explosive (3) is formed by mixing and granulating PYX-based explosive molding powder and graphite.

4. The ultra-high temperature deep-penetrating projectile according to claim 1, characterized in that, The cartridge case (2) is made of alloy steel and has a yield strength of over 1600 MPa.

5. A high-temperature deep-penetration projectile according to any one of claims 1-4, characterized in that, The high-tungsten powder shaped charge (4) is composed of a first arc-shaped segment (41), a conical segment A (42), a conical segment B (43), and a second arc-shaped segment (44) connected in sequence.

6. The ultra-high temperature deep-penetrating projectile according to claim 5, characterized in that, The radius of the first arc segment (41) ranges from 2 to 6 mm; The cone angle of cone segment A (42) ranges from 40° to 44°, and the cone angle of cone segment B (43) ranges from 44° to 48°. The radius of the second arc segment (44) ranges from 50 to 100 mm.

7. The ultra-high temperature deep-penetrating projectile according to claim 6, characterized in that, The wall thickness of the first arc segment (41) and the second arc segment (44) are both variable wall thickness structures, with a wall thickness range of 1-4 mm.

8. The ultra-high temperature deep-penetrating projectile according to claim 1, characterized in that, The ultra-high temperature deep-penetrating bullet has a perforation depth of 852-890mm and a temperature resistance of 260℃.

9. The method for preparing the ultra-high temperature deep-penetrating projectile according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Preparation of the drug-formation liner: S1.1, Mixing powder The mixture of 80%-85% tungsten powder, 10%-15% copper powder, and other auxiliary materials is ball-milled under argon protection to obtain a uniform mixed powder. S1.2, Press the mixed powder; S1.3 The pressed shaped charge liner is sintered by vacuum reduction sintering process to obtain a high tungsten powder charge liner (4). S2. Place the PYX detonator (1) into the detonation hole (23) of the cartridge case (2), and at the same time, according to the type of perforated projectile, evenly cover the detonator with the PYX base explosive (3) and put it into the inner cavity of the cartridge case. S3. Apply adhesive evenly to the outer surface of the shaped charge liner and place it on the PYX-based main explosive (3); Pressing is performed at a pressure of not less than 18 MPa; S4. After pressing, apply sealing glue (5) evenly to the connection between the cartridge case (2), PYX-based main explosive (3) and high tungsten powder shaped charge (4), and seal it with sealing glue (5).

10. The preparation method according to claim 9, characterized in that, Specifically, S1.3 involves heating at a rate of 10–12 °C / min, holding at 1100 °C for 1 hour, then cooling at a rate of 5 °C / min, holding at 350 °C for 1 hour, and then cooling down to room temperature with the furnace.

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