Shaped Charge Liner Research Articles

Development and Application of the 40-Type Perforator for Casing Deformation Wells

To address the inability of the 40-type small-diameter perforator to meet the perforation requirements of 5 1/2" deformed casing in horizontal wells, a perforating gun tube with a wall thickness of 3.2 mm and 160-grade steel was designed. This design effectively increased the available internal space within the gun body, enhancing the perforating gun's resistance to detonation-induced deformation under increased charge conditions. Consequently, the single-shot perforating charge was increased from 3 grams to 4 grams. In terms of the gun and charge design, the limited internal space of the gun was maximized, and a shaped charge liner structure was adopted to enable high-clearance distal perforation, ensuring both perforation depth and casing hole diameter. The newly developed 40-type perforator has been widely applied in blocks such as the National Demonstration Platform for Reservoir Stimulation in northern Dianqian, becoming an effective technological solution for perforation operations in deformed casing wells.

Characterization of slugs for self-designed Ti-alloy shaped charge liner after penetrating reinforced concrete and steel target

Characterization of slugs for self-designed Ti-alloy shaped charge liner after penetrating reinforced concrete and steel target

Preliminary study on the dynamic deformation mechanism of CoCrFeNi high-entropy alloy and its application in the shaped charge liner

High-entropy alloys (HEAs) with a face-centered cubic structure offer numerous advantages, including high plasticity, good processability, and high-temperature resistance. They are also suitable for use as materials in shaped-charge liners, which can cause significant damage. In this study, CoCrFeNi HEAs were prepared, and their mechanical characteristics were examined. The results indicated that the alloy exhibited good plasticity and processability. After dynamic compression, the samples were analyzed using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). It was found that dislocation was the primary deformation mechanism at low strain rates. However, as the strain rate increased, the deformation mechanism shifted from dislocations to a combination of dislocations and twinning. The damage performance of the CoCrFeNi HEA was verified through a static penetration experiment using a conical charge. The results were then compared with simulation results obtained using the AUTODYN software. This study demonstrated that the CoCrFeNi HEA could form a condensed, stable-shaped charge jet, leading to efficient damage after penetrating the steel target plate. Therefore, after uniform treatment, the CoCrFeNi HEA can be utilized as a high-energy structural material to design shaped charge structures that achieve highly efficient damage.

Machine learning optimization strategy of shaped charge liner structure based on jet penetration efficiency

Shaped charge liner (SCL) has been extensively applied in oil recovery and defense industries. Achieving superior penetration capability through optimizing SCL structures presents a substantial challenge due to intricate rate-dependent processes involving detonation-driven liner collapse, high-speed jet stretching, and penetration. This study introduces an innovative optimization strategy for SCL structures that employs jet penetration efficiency as the primary objective function. The strategy combines experimentally validated finite element method with machine learning (FEM-ML). We propose a novel jet penetration efficiency index derived from enhanced cutoff velocity and shape characteristics of the jet via machine learning. This index effectively evaluates the jet penetration performance. Furthermore, a multi-model fusion based on a machine learning optimization method, called XGBOOST-MFO, is put forward to optimize SCL structure over a large input space. The strategy's feasibility is demonstrated through the optimization of copper SCL implemented via the FEM-ML strategy. Finally, this strategy is extended to optimize the structure of the recently emerging CrMnFeCoNi high-entropy alloy conical liners and hemispherical copper liners. Therefore, the strategy can provide helpful guidance for the engineering design of SCL.

Studying the Effectiveness of Shaped Charge Jets Created by Graphene-containing Shaped Charge Liners

The paper presents selected results of studies conducted within the framework of the following research project: “Use of graphene and new multilayer explosive technologies in materials for shaped charge liners" (The National Centre for Research and Development in Poland: project No: DOB-BI08/03/01/2016). This study was performed by a consortium made up of the following entities: Institute of Precision Mechanics, Military University of Technology and the Mototechnika company (Poland). The main objective of the performed experiments was to test the effectiveness of shaped charge liners produced with the use of powder metallurgy methods, from mixtures containing copper powder and graphene-coated copper powder. The content of the latter equaled 0%, 1%, 5% and 10%, respectively. Shaped charge jets created with the use of liners made from the powder mixtures tested were recorded with the help of X-ray technology. Firing tests were conducted against steel barriers and the depth of penetration was determined. The obtained results showed that the addition of graphene powder to pure copper powder practically does not increase the depth of penetration of the shaped charge jet compared to scenarios in which sintered liners without this additive were used.

Research on directional rock blasting based on different slotted pipe materials of the combined charge structure

For shaped charge blasting projects in mining, civil engineering, and similar fields, it is proposed to modify the charge structure by combining slotted tubes and shaped charge liners to obtain a new type of charge structure. This aims to achieve directional rock breaking through the focused action of the shaped charge. The influence of different slotted pipe materials on the directional rock-breaking effect of concentrated energy using a new charge structure is explored through theoretical analysis combined with model test study, high-speed camera, stress–strain gauge, and other equipment. A comparison is made between slotted pipes made of aluminum, kraft paper, and PVC, with the cutting width of 2 mm. Based on the characteristics of the cracks formed after blasting, the new charge structure made of aluminum slotted pipe produces a penetrating crack that is almost consistent with the pre-cracking direction. Based on the corresponding characteristics of successively released blasting energy, the guiding and convergence effect of the new charge structure made of aluminum slotted pipe on the explosion energy is greater than that of the new charge structure made of the other two types of slotted pipe material. According to the strain data measured after blasting, the peak arrival time of the strain peak in the direction of the slotted pipe on one side of the shaped hood is shorter than that in the other two directions, and the peak strain is greater than that in the other two directions while having a better energy gathering effect. Based on the findings, the new charge structure with directional energy concentration has a damage reduction effect. Furthermore, the material of aluminum slotted pipe is found to be better than PVC slotted pipe, whereas the material of PVC slotted pipe is better than kraft paper slotted pipe in achieving directional rock breaking.

Effect of tungsten contents on the jet penetration performance of shaped charge liner based copper-tungsten composites

Herein, we investigated the effect of W content on the jet penetration performance of W-Cu shaped charge liners by using both simulation and experimental methods. The W-Cu composite liners were prepared directly by using spark plasma sintering (SPS) technique. Microstructural observations showed that W particles were uniformly dispersed within the Cu matrix. The relative density of W-Cu composites decreased slightly from 99.2% to 98.8% with an increase in the W content. The hardness of the W-Cu composite liner increased as increasing W content and reached the highest value of 209.2 HV for the composite reinforced by 60 wt.% W. Besides, the penetration depth increased and reached the maximum value of 80 mm for the composite liner containing 50 wt.% W which is improved by about 11% compared to pure Cu liner. According to simulation and experiment results, the penetration depth of the W-Cu composite liners exhibits a nearly identical trend. W-Cu composite liner containing 50 wt.% W remains the best performance compared to other composites. However, the experimental results are lower compared to the simulation results. This could be because the simulation procedure did not completely account for the actual test conditions.

Cold extrusion of a shaped charge liner preform with hyperboloid structure: simulation and experiment

Cold extrusion of a shaped charge liner preform with hyperboloid structure: simulation and experiment

Directional rock blasting using shaped charges using combined charge liners with different shapes

AbstractThe shape of a charge liner used in shaped charges with a combined liner will greatly influence the blasting effect. In this study, we examined how combined charge liners with different shapes affected directional rock blasting, and we assessed the influence mechanism. The numerical simulation results showed that among the three shaped charge liners, liners with arc and triangular shapes performed significantly better than the flat‐top liner, and the triangular liner was slightly superior to the arc‐shaped liner. Model testing indicated that principal cracks in the arc‐shaped and triangular liners developed along the combined energy‐gathering direction, while the principal cracks of the flat‐top liner deviated 32° from the axis. Therefore, the directional cracking effect of arc‐shaped and triangular liners was superior to the flat‐top liner. According to the peak strain values on the liners, the peak strain in the combined energy‐gathering direction was greater than that in the slot and nonenergy‐gathering directions, and the order of the peak strain of the three liners followed arc‐shaped liner > triangular liner > flat‐top liner. The directional blasting effect of the triangular liner was slightly better than the arc‐shaped liner. In conclusion, the findings of this study suggested that the best directional rock‐blasting effect was achieved when the shape of the combined charge liner was triangular.

Shaped Charge Liner Collapse and Jet Formation by Electromagnetic Loading on High Pulsed Power Generator

Shaped Charge Liner Collapse and Jet Formation by Electromagnetic Loading on High Pulsed Power Generator

Study on the forming characteristics of polytetrafluoroethylene/copper jet with different preparation processes

In this paper, PTFE/Cu composite material for liner is taken as the research object, and the preparation process and jet forming characteristics of PTFE/Cu composite liner are studied. The liners were prepared by extrusion molding, molded sintering and hot-pressing sintering. Due to different preparation processes, different microstructures of the liner can occur, including defects such as pores and microcracks, resulting in different strength and density of the liner, leading to differences in the forming characteristics of the jet. Therefore, the forming process of the jet was simulated by the finite element numerical simulation software. It was found that there was obvious radial expansion effect in the head of the jet, but with the increase of density, the radial expansion effect was weakened, and the jet velocity decreased gradually. The strength and densification of the shaped charge liner prepared by different processes were different. The densification of the molded sintering liner was generally better than that of the other two kinds of shaped charge liners. As a result, the velocity of the jet formed by the molded sintering liner is always the highest, with a numerical simulation velocity of 6642 m/s and an experimental velocity of 6534.7 m/s. The second is the jet of the hot-pressing sintering liner and the lowest velocity is the jet of the extrusion molding cover, with a numerical simulation velocity of 6482 m/s, while the experimental velocity is only 6397.9 m/s. The jet velocity measured by the pulse X-ray experiment was compared with the velocity of the numerical simulation, and the error was within 2.96%, which verifies the accuracy of the numerical simulation.

Jet formation and penetration performance of a double-layer charge liner with chemically-deposited tungsten as the inner liner

This paper proposes a type of double-layer charge liner fabricated using chemical vapor deposition (CVD) that has tungsten as its inner liner. The feasibility of this design was evaluated through penetration tests. Double-layer charge liners were fabricated by using CVD to deposit tungsten layers on the inner surfaces of pure T2 copper liners. The microstructures of the tungsten layers were analyzed using a scanning electron microscope (SEM). The feasibility analysis was carried out by pulsed X-rays, slug-retrieval test and static penetration tests. The shaped charge jet forming and penetration law of inner tungsten-coated double-layer liner were studied by numerical simulation method. The results showed that the double-layer liners could form well-shaped jets. The errors between the X-ray test results and the numerical results were within 11.07%. A slug-retrieval test was found that the retrieved slug was similar to a numerically simulated slug. Compared with the traditional pure copper shaped charge jet, the penetration depth of the double-layer shaped charge liner increased by 11.4% and >10.8% respectively. In summary, the test results are good, and the numerical simulation is in good agreement with the test, which verified the feasibility of using the CVD method to fabricate double-layer charge liners with a high-density and high-strength refractory metal as the inner liner.

Study on the Effect of PTFE/Cu Composite Material Preparation Process on Penetration Performance.

The jet formed by the traditional metal liner has a slender shape. The diameter of the jet head is consistent with that of the tail, and the ductility is good. When it is used to penetrate the target, it has a good damage effect. The low-density jet formed by the PTFE/Cu liner, according to the different preparation processes and densities, has different degrees of radial expansion. This phenomenon may lead to the expansion of the jet head during the penetration process, resulting in a damage effect, which is different from the previous jet on the target. In this paper, the numerical simulation of PTFE/Cu liners with different preparation processes penetrating steel targets is carried out, and the effects of different preparation processes and liner density on the penetration characteristics of jets penetrating steel targets are compared and analyzed. The PTFE/Cu shaped charge liner was processed according to different preparation processes, and the jet penetration steel target experiment was carried out, so as to verify and analyze the numerical simulation results.

Research of influence of different shaped charge liner materials on penetration depth using numerical simulations

Research of influence of different shaped charge liner materials on penetration depth using numerical simulations

Influence of liner structure on EFP formation and penetration performance of a Ta-Zr liner

In order to study the formation and penetration performance of reactive liner, in this paper, a Ta-Zr alloy is used as the liner material, and large cone angle liner, spherical liner and arc-cone liner are simulated and analyzed by using AUTODYN software. The following conclusions are obtained: (1) The EFP formed by large cone angle liner has good flight stability, followed by arc cone liner; (2) The length diameter ratio of spherical shaped charge liner is larger than that of arc cone shaped charge liner; (3) The EFP penetration depth of the arc cone shaped liner is larger, and the EFP incident aperture of the large cone angle shaped liner is larger.

Damage performance of a shaped charge liner fabricated from Ti-29Nb-13Ta-4.6Zr alloy

The change of the liner material directly affects the penetration and damage performance of the shaped charge. In this paper, Ti-29Nb-13Ta-4.6Zr (TNTZ) was used as the charge liner. Autodyn software was used to analyze the jet formation of TNTZ liner, then static explosion test was conducted to analyze the penetration and damage performance of charge liners. The following conclusions were obtained: A charge liner structure was proposed for TNTZ alloy, the simulation shows that a jet with acceptable L/D ratio was formed, and the jet head velocity was around 6000 m/s. The TNTZ charge liner successfully ignited fuel tank after penetrating steel target due to chemical reaction. For the tests on C35 concrete targets, the TNTZ liner has horizontal damage effect which leads to penetration tunnel with large diameter, however the penetration depth is smaller compared to Cu liner. Such behavior makes TNTZ liner a good candidate as forward shaped charge of tandem warheads.

Numerical simulation of penetration behavior of RHA target with biconical liner

The AUTODYN-2D simulation software was used to study the jet formation of single-cone and biconical shaped charge liner and the damage influence on the RHA target. The numerical simulation results show that compared with the typical single-cone shaped charge structure, the jet head formed by the biconical liner is faster and has better penetration performance on the RHA target. On this basis, the influence of standoff, liner cone angle and line thickness on the penetration characteristics of RHA target under biconical shaped charge was studied. The simulation results show that when the standoff increases from 2.0CD to 3.0CD, the penetration depth increases gradually. When the upper cone angle is 30° and the lower cone angle increases from 40° to 60°, the penetration depth of the formed jet to the target decreases gradually. When the liner thickness increases from 5mm to 6mm, the penetration depth is obviously improved.

Effect of Annealing Temperature on Mechanical Properties, Microstructure and Penetration of Shear Formed C10100 Copper Shaped Charge Liners

Effect of Annealing Temperature on Mechanical Properties, Microstructure and Penetration of Shear Formed C10100 Copper Shaped Charge Liners

Structural design of the fluted shaped charge liner using multi-section optimization method

Spin effect of the small diameter shaped charge results in the centrifugal stress during the jet stretching process. Consequently, the jet scatters, which deceases the jet penetration capability. In the present study, a multi-section method was proposed to design the spin-compensation liner. The spin-compensation rate (SCR) of the liner was defined as the specific angular velocity that a fluted liner can offset. Based on the plain stress theory, SPH numerical method was applied to study the converging process of the 2D fluted structure. The spin-compensation mechanism of the fluted structure was illustrated. Then, nine cross sections were chosen along the liner axis equidistantly. On each of the section, a 2D fluted structure was designed to offset a given initial angular velocity. After, the optimized fluted structures were integrated into a 3D fluted liner. Jet appearances of the normal liner and the fluted liners under different initial angular velocities were compared, which verifies the practicality of the multi-sectional method. The multi-section optimization method provides a new efficient method of designing the shaped charge liner for a specific usage.

Detonation Wave Propagation of Double-Layer Shaped Charge and Its Driving Characteristics to the Liner

The double-layer charge can effectively improve the axial driving ability of explosives, which shows a considerable engineering application prospect in highly efficient damage warheads. Due to the complex wave structure produced by the overpressure detonation of a double-layer charge, a series of dynamic behaviors inside the shaped charge liner will be affected. By comparing the detonation wave shapes of single-layer charge and double-layer shaped charge structure and the jet shaping parameters of a double-layer shaped charge with different structural parameters, the evolution of detonation wave and the state parameters in the wave system are analyzed in this research. The research found that the double-layer charge with high detonation velocity in the outer layer and low detonation velocity in the inner layer can produce continuous overpressure detonation, which makes the overpressure detonation state be applied efficiently. Meanwhile, this study found that the overpressure detonation field formed by the double-layer charge changes the action law of the traditional single charge on the shaped charge liner. The detonation waveform of the entire charge is controlled by different detonation velocities and detonation energies, and a detonation waveform that matched well with the shaped charge liner is obtained. This study solves the matching relationship between the structure of the overpressure detonation wave system and the properties of a double-layer charge, which is of great value for improving the detonation-driving effect of condensed explosives on surrounding media. The double-layer charge can effectively enhance the potential of explosive charge. It is not only widely used in military fields such as improving the armor-breaking power of shaped charge penetrators and improving the muzzle velocity and concentration of fragments of directional warheads, but also can promote the development of industrial fields such as explosive processing.