Segment presses for powder metal hollow charge inserts

Abstract

A shaped charge insert can comprise a plurality of insert segments for a shaped charge configured to perforate the sidewall of a borehole upon detonation. The plurality of insert segments can include a tip insert segment, comprising a first group of compacted metal powder having a hollow conical shape with a rear interface end opposite a tip end. The tip insert segment is configured to be placed within a shaped charge casing. The plurality of insert segments can also include a base insert segment, comprising a second group of compacted metal powder having a hollow truncated conical shape with a rear base end opposite a front base interface end.The rear base end has a larger diameter than the front base interface end, and the base insert segment is configured to be located at least partially within the shaped charge housing.

Description

BACKGROUND

[0001] After drilling a wellbore in a subterranean formation to retrieve hydrocarbons such as oil and gas located below the surface, a casing string may be inserted into the wellbore. Generally, the casing string protects the wellbore from failure (e.g., collapse, erosion) and provides a fluid pathway for hydrocarbons during production. Traditionally, the casing string is cemented to the wellbore. To develop the hydrocarbons for production, a perforating gun system may be inserted into the casing string via a toolstring. The toolstring (e.g., a tubing string, wireline, slickline, coiled string) lowers the perforating gun system into the casing string to a desired position in the wellbore.Once the perforation gun system is positioned so that the shaped charges are adjacent to a subterranean formation containing hydrocarbons, the shaped charges are ignited. The detonation perforates the casing string, the cement, and the subterranean formation, allowing hydrocarbons to flow through the perforation into the casing string.

[0002] Traditionally, shaped charges enclose an explosive material that propel a metal liner outward in a jet to perforate a target material (e.g., casing string, cementing, subterranean formation) upon detonation. Various properties of the metal liner (e.g., material, shape, size, density, etc.) can affect the velocity, momentum, length, and stability of the jet formation. For example, increasing the density at the tip of an liner and / or decreasing the density at the base of the liner can alter the velocity and momentum gradients of the jet. A high-velocity jet may be ideal for penetrating relatively hard target materials. However, in some situations, a higher density in the center of the liner or at the base of the liner may be ideal for penetrating target materials.

[0003] Unfortunately, current manufacturing techniques, which involve spinning metal powder in a centrifugal die and pressing the metal powder to form the insert, do not readily allow for intentional density variations within the insert. In fact, spinning the metal powder expels lower-density particles outward, so metal inserts are generally denser near the tip of the insert, which can limit their effectiveness with some target materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] These drawings illustrate certain aspects of some embodiments of the present disclosure and should not be used to limit or define the method. Fig. 1 illustrates a partial cross-sectional side view of an operating environment for a drilling and completion system according to some embodiments of the present disclosure. Fig. 2 illustrates a cross-sectional view of a downhole perforating gun system according to some embodiments of the present disclosure. Fig. 3 illustrates a sectional view of a shaped charge for the borehole perforating gun system according to some embodiments of the present disclosure. The Fig. 4A-4E illustrate various views of a tip press assembly forming a tip liner segment for the shaped charge according to some embodiments of the present disclosure. The Fig. 5A-5E illustrate various views of a base press assembly forming a base liner segment for the shaped charge according to some embodiments of the present disclosure. Fig. 6 illustrates a cross-sectional view of the shaped charge having a plurality of liner segments with interface features according to some embodiments of the present disclosure. The Fig. 7A-7B illustrate cross-sectional views of a secondary press assembly configured to press a plurality of liner segments into a continuous liner according to some embodiments of the present disclosure. Fig. 8 illustrates a cross-sectional view of the continuous liner disposed within the shaped charge according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0005] Disclosed herein are systems and methods for segmented shaped charges used in downhole perforation gun systems configured to perforate materials downhole (e.g., casing string, cementing, subterranean formation). In particular, the segmented shaped charges each comprise a plurality of liner segments. As detailed below, the liner segments 312 can each be formed with specific properties (e.g., material, shape, size, density, etc.) and aligned within a corresponding shaped charge 120 such that the resulting liner of the shaped charge 120 can have a particular density gradient as well as other properties for perforating a target material downhole.

[0006] Fig. 1 illustrates a partial cross-sectional side view of an operating environment for a drilling and completion system according to one or more embodiments of the disclosure. It should be noted that during Fig. 1 generally shows a land-based drilling and completion assembly, those skilled in the art will readily recognize that the principles described herein are also applicable to subsea drilling and completion operations utilizing floating or sea-based platforms and rigs without departing from the scope of the disclosure. As illustrated, the drilling and completion assembly 100 includes a platform 102 supporting a derrick 104 having a traveling block 106 for raising and lowering a tool string 108. The tool string 108 includes, among other things, a work string 110, a perforation gun system 112, and any other suitable tooling well known to those skilled in the art. Although not shown, a tubular string, wireline, slickline, and / or coiled string may be used in place of the work string 110 to support the perforation gun system 112.

[0007] The workstring 110 is configured to lower the perforation gun system 112 into a wellbore 114. As illustrated, the wellbore 114 may be lined with a casing 116 cemented to a wellbore wall 118. The casing 116 is configured to protect the wellbore 114 from failure (e.g., collapse, erosion) and to provide a fluid path for hydrocarbons during production. To access the hydrocarbons, the workstring 110 lowers the perforation gun system 112 into a position such that the shaped charges 120 are disposed adjacent to a subterranean formation 122 containing the hydrocarbons, and the perforation gun system 112 ignites the shaped charges 120. In some embodiments, the shaped charges 120 may be ignited by the perforation gun system 112.The detonations perforate the casing 116, the cementation, and the subterranean formation 122 in the respective paths of the detonations of the shaped charge 120, allowing hydrocarbons to flow through the perforations into the casing string 116.

[0008] Fig. Figure 2 illustrates a cross-sectional view of a downhole perforating gun system according to some embodiments of the present disclosure. The perforating gun system 112 includes the gun body 200 (e.g., gun carrier). The gun body 200 is configured to house a charge tube 202. In the illustrated embodiment, the charge tube 202 includes a generally cylindrical shape. However, the charge tube 202 may have any suitable shape. Further, the perforating gun system 112 may include a plurality of attachment devices 204 configured to secure the charge tube 202 within the gun body 200. The fastening devices 204 can radially secure the charge tube 202 within the gun body 200 to prevent the outer surface 206 of the charge tube 202 from contacting the inner surface 208 of the gun body (200).In the illustrated embodiment, the attachment devices 204 include a first set of attachment devices 210 secured to an interior portion 212 of the gun body 200 near a first axial end 214 of the gun body 200, and a second set of attachment devices 216 secured to the interior portion 212 of the gun body 200 near a second axial end 218 of the gun body 200. In some embodiments, the perforation gun system 112 may include additional attachment devices 204 for further securing the charge tube 202.

[0009] In addition, the perforation gun system 112 also includes at least one shaped charge 120 (e.g., a first shaped charge 220, a second shaped charge 222, a third shaped charge 224, and a fourth shaped charge 226). The at least one shaped charge 120 can be mounted within the charge tube 202. At a desired location in the wellbore, the at least one shaped charge 120 is configured to detonate to perforate the casing 116, the cementing, and the subterranean formation 122. An ignition device 228 of the perforation gun system 112 can be configured to trigger the ignition of the shaped charges 120. As illustrated, the ignition device 228 can include a fuse 230 connected to each shaped charge 120 mounted within the charge tube 202.

[0010] Fig. 3 illustrates a cross-sectional view of a shaped charge 120 for the borehole perforation gun system according to some embodiments of the present disclosure. The shaped charge 120 includes a shaped charge casing 300 configured to house a segmented shaped charge liner 302 and an explosive material 304. The explosive material 304 can be disposed near a trigger end 306 of the shaped charge casing 300 between an inner surface 308 of the shaped charge casing 300 and an outer surface 310 of the segmented shaped charge liner 302. Upon detonation, the explosive material 304 is configured to collapse and eject the segmented shaped charge liner 302 in a jet to perforate a target material (e.g., a borehole sidewall).

[0011] As illustrated, the segmented shaped charge liner 302 includes a plurality of liner segments 312 configured to be stacked within the shaped charge casing 300. Each liner segment 312 can be formed with specific properties (e.g., material, shape, size, density, density gradient, etc.) and aligned within the shaped charge casing 300 so that the segmented shaped charge liner 302 can have a particular density gradient as well as other properties for perforating a target material in the wellbore. In the illustrated embodiment, the plurality of liner segments 312 includes a tip liner segment 314, a first intermediate liner segment 316, a second intermediate liner segment 318, and a base liner segment 320, which are arranged one above the other to form the segmented shaped charge liner 302 having a hollow conical shape.However, any number of liner segments 312 may be used to form the segmented shaped charge liner 302. For example, the plurality of liner segments 312 may include only the tip liner segment 314 and the base liner segment 320. Alternatively, the plurality of liner segments 312 may include one or more intermediate liner segments stacked between the tip liner segment 314 and the base liner segment 320 to form the segmented shaped charge liner 302.

[0012] The tip insert segment 314 is configured to be disposed within the shaped charge casing 300 proximate the trigger end 306 of the shaped charge casing 300. The tip insert segment 314 includes a first group 322 of compacted metal powder having a hollow cone shape with a tip end 324 and a rear interface end 326 opposite the tip end 324. The first group 322 of compacted metal powder may include a metal, a coated metal, or a metal alloy powder selected from the group consisting of iron, steels, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, alloys thereof, and combinations thereof. A small amount of graphite may be included to act as a lubricant. Further, the first group 322 of compacted metal powder may be in a green state.That is, the first group 322 of metal powder is pressed into the desired shape, but is not sintered or otherwise fused into a solid liner segment. Fusing the metal powder into a solid liner segment can adversely affect finishing operations because the solid liner segment may leave behind a piece of metal blocking the hole formed by other sections of the segmented shaped charge liner 302.

[0013] Furthermore, as illustrated, the tip liner segment 314 may be formed with a rounded tip end 324 having a radius between 0.03 and 0.5 inches (e.g., between 0.0762 and 1.27 centimeters). However, the tip end 324 may have any suitable shape. Further, the tip end 324 may be located closer to the trigger end 306 of the shaped charge casing 300 than the rear interface end 326 of the tip liner segment 314 such that a diameter (e.g., an inner and / or outer diameter) of the tip liner segment 314 increases in a direction toward a base casing end 328 of the shaped charge casing 300. The diameter of the tip liner segment 314 may increase based at least in part on a cant angle 330 of the tip liner segment 314. In particular, a larger inclination angle 330 may result in a larger diameter of the tip insert segment 314 at the rear interface end 326.The inclination angle 330 of the tip liner segment 314 can be between 10.0 and 45.0 degrees. Furthermore, the inclination angle 330 of the tip liner segment 314 can be greater than a casing inclination angle 332 of the shaped charge casing 300, such that a radial width of the gap between an outer surface 334 of the tip liner segment 314 and the inner surface 308 of the shaped charge casing 300 decreases toward the rear interface end 326 of the tip liner segment 314.

[0014] An axial length of the tip liner segment 314, from the tip end 324 to the rear interface end 326, may be between 12.0 and 50.0 percent of a combined axial length of the plurality of liner segments 312 for a segmented shaped charge liner 302 having two to eight liner segments 312. However, in some embodiments, the axial length of the tip liner segment 314 may be between 15.0 and 35.0 percent of the combined axial length of the plurality of liner segments 312 for a segmented shaped charge liner 302 having two to eight liner segments 312. Furthermore, the axial length of each liner segment of the plurality of liner segments 312 may be between 12.0 and 50.0 percent of the combined axial length of the plurality of liner segments 312 for a segmented shaped charge liner 302 having two to eight liner segments 312.However, the axial length of each liner segment may be greater (e.g., between 30.0 and 60.0 percent) for a segmented shaped charge liner 302 with two or three liner segments 312, and less (e.g., between 10.0 and 25.0 percent) for a segmented shaped charge liner 302 with more than four liner segments 312. Furthermore, each of the liner segments 312 may have a specific axial length based at least in part on a desired density gradient profile for the segmented shaped charge liner 302. For example, in the illustrated embodiment, the axial lengths of the liner segments 312 gradually decrease from the tip liner segment 314 to the base liner segment 320 such that the density of the segmented shaped charge liner 302 near the tip liner segment 314 is greater than the density near the base liner segment 320. Alternatively, each of the liner segments 312 may have the same axial length.

[0015] The average thickness of the tip insert segment 314 may be between 0.015 and 0.150 inches (e.g., between 0.0381 and 0.381 centimeters). As stated above, the tip insert segment 314 comprises a hollow cone shape. The thickness of the tip insert segment 314 may be measured between an inner surface 336 of the tip insert segment 314 and the outer surface 334 of the tip insert segment 314. In some embodiments, the thickness of the tip insert segment 314 may increase in the axial direction from the tip end 324 to the rear interface end 326. Alternatively, the tip insert segment 314 may have a uniform thickness. Furthermore, the average thickness of each insert segment may be between 0.015 and 0.250 inches (e.g., 0.0381 to 0.635 centimeters). In some embodiments, the average thickness of each liner segment 312 may increase toward a base end 338 of the segmented shaped charge liner 302.For example, as illustrated, the respective average thicknesses may be 0.035 inches (e.g., 0.0889 centimeters) for the tip liner segment 314, 0.036 inches (e.g., 0.09144 centimeters) for the first intermediate liner segment 316, 0.05 inches (e.g., 0.127 centimeters) for the second intermediate liner segment 318, and 0.065 inches (e.g., 0.1651 centimeters) for the base liner segment 320. However, the thickness at each end of the respective liner segments 312 may be the same as that of a corresponding end of an adjacent liner segment to create an interface.

[0016] Each liner segment 312 may include at least one interface end 340 configured to interface with a corresponding interface end of an adjacent liner segment. For example, in the illustrated embodiment, the tip liner segment 314 includes the rear interface end 326 mated with a front first intermediate interface end 342. The rear interface end 326 and the front first intermediate interface end 342 may have the same inner and outer diameters so that the respective interface ends 340 can be aligned and form the continuous inner surface 344 and outer surface 310 for the segmented shaped charge liner 302 between the adjacent liners 312.Further, a rear first intermediate interface end 346 of the first intermediate liner segment 316 may be mated to a front second intermediate interface end 348 of the second intermediate liner segment 318, and a rear second intermediate interface end 350 of the second intermediate liner segment 318 may be mated to a front base interface end 352 of the base liner segment 320. Alternatively, in an embodiment having only the tip liner segment 314 and the base liner segment 320, the rear interface end 326 of the tip liner segment 314 may be mated to the front base interface end 352 of the base liner segment 320.

[0017] Furthermore, as stated above, the plurality of insert segments 312 may include at least one intermediate insert segment disposed between the tip insert segment 314 and the base insert segment 320. In the illustrated embodiment, the at least one intermediate insert segment includes the first intermediate insert segment 316 disposed adjacent the tip insert segment 314 and the second intermediate insert segment 318 disposed adjacent the base insert segment 320. The at least one intermediate insert segment comprises a second group 354 of compacted metal powder having a hollow frustoconical shape with a front intermediate interface end (e.g., the front first intermediate interface end 342) and a rear intermediate interface end (e.g., the rear first intermediate interface end 346).The second group 354 of compacted metal powder may comprise a metal or metal alloy powder selected from the group consisting of iron, steels, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, alloys thereof, and combinations thereof. The second group 354 of compacted metal powder may be composed of the same metal or metal alloy as the first group 322 of compacted metal powder. Alternatively, the second group 354 of compacted metal powder may include a different metal or metal alloy than the first group 322 of compacted metal powder. Further, the second group 354 of compacted metal powder may be in a green state.Additionally, since the at least one intermediate insert segment has a hollow truncated cone shape, the front intermediate interface end and the rear intermediate interface end may have a circular or annular cross-section. Additionally, the rear intermediate interface end has a larger diameter than the front intermediate interface end.

[0018] Further, the plurality of insert segments 312 includes the base insert segment 320, which comprises a third group 356 of compacted metal powder having a hollow frustoconical shape. The third group 356 of compacted metal powder may comprise a metal or metal alloy powder selected from the group consisting of iron, steels, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, alloys thereof, and combinations thereof. The third group 356 of compacted metal powder may be composed of the same metal or metal alloy as the first group 322 and / or the second group 354 of compacted metal powder. For example, the first group 322, the second group 354, and the third group 356 of compacted metal powder may each include copper and tungsten materials, possibly in different proportions.Alternatively, the third group 356 of compacted metal powder may include a different metal or metal alloy than the first group 322 and / or the second group 354 of compacted metal powder. For example, the first group 322 of compacted metal powder may include a copper and tungsten material, and the second group 354 and the third group 356 of compacted metal powder may each include a steel material. Further, the base insert segment 320 includes the front base interface end 352 and a rear base end 358, each having a circular or annular cross-section. The rear base end 358 may have a larger diameter than the front base interface end 352.In some embodiments, an outer diameter at the rear base end 338 of the base liner segment 320 may be sufficiently large such that an outer surface of the base liner segment 320 contacts the inner surface 308 of the shaped charge casing 300. Such contact may at least partially seal the explosive material 304 from the base casing end 328 of the shaped charge casing 300.

[0019] The Fig. 4A-4E illustrate various views of a tip press assembly 400 forming a tip insert segment 314 for the shaped charge according to some embodiments of the present disclosure. In particular, Fig. 4A is a cross-sectional view of a tip press assembly 400 for forming the tip insert segment 314. As illustrated, the tip press assembly 400 includes a tip die 402 and a tip punch 404. The tip die 402 may be a conical tip die 402 configured to receive a corresponding conical tip punch 404 to form a tip insert segment 314 having a hollow conical shape. In the illustrated embodiment, the tip die 402 is oriented such that the diameter of an inner wall 406 of the tip die 402 increases in an upward direction 408. That is, the inner wall 406 of the tip die 402 may be angled with respect to a central axis 410 of the tip die 402 such that the tip die 402 may form the tip insert segment 314 with a hollow cone shape.Furthermore, a bottom of the tip die 402 may be rounded so that the tip end 324 of the tip insert segment 314 may be a rounded tip end 324. However, the bottom of the tip die 402 may have any suitable shape for forming the tip end 324 of the tip insert segment 314.

[0020] Fig. 4B illustrates the tip press assembly 400 after receiving the first group 322 of metal powder according to some embodiments of the present disclosure. As illustrated, the tip die 402 (e.g., the conical tip die 402) is configured to receive the first group 322 of metal powder. A desired amount of the first group 322 of metal powder can be introduced into the tip die 402. As set forth above, the first group 322 of metal powder can comprise a metal or metal alloy powder selected from the group consisting of iron, steels, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, alloys thereof, and combinations thereof. Further, the first group of metal powder can settle near the bottom 412 of the tip die 402.

[0021] Fig. 4C illustrates the tip press assembly 400 with a rotating tip die 402 according to some embodiments of the present disclosure. The tip die 402 may include a die section 414 rotatably housed within an outer housing 416. That is, the die section 414 may be configured to rotate within the outer housing 416 about the central axis 410 of the tip die 402. Additionally, the tip die 402 may include an actuator (not shown) configured to drive rotation of the die section 414 relative to the outer housing 416. By rotating the die section 414, the first group 322 of metal powder may be propelled outward and upward by centrifugal force on the inner wall 406 of the die section 414 of the tip die 402.When the first group 322 of metal powder is driven outward and upward by centrifugal force on the inner wall 406, the metal particles of the first group 322 of metal powder can be separated according to their density. In particular, particles with a lower density can be driven toward an upper end of the inner wall 406.

[0022] Fig. 4D illustrates the tip press assembly 400 with the tip punch 404 compressing the first group 322 of metal powder against the tip die 402 according to some embodiments of the present disclosure. Indeed, the tip punch 404 (e.g., the conical tip punch 404) is configured to compress the first group 322 of metal powder against the inner wall 406 of the tip die 402 (e.g., the conical tip die 402) to compact the first group 322 of metal powder and form the tip insert segment 314 having a hollow cone shape. As stated above, the first group 322 of compacted metal powder may be in a green state. That is, the first group 322 of metal powder may be compacted into the desired hollow cone shape, but not sintered or otherwise fused into a solid insert segment.Further, the tip punch 404 may be configured to compress the first group 322 of metal powder against the inner wall 406 after rotation or during rotation of the tip die 402, such that the lower density particles of the first group 322 of metal powder are located near the top end 418 of the inner wall 406. Compressing the first group 322 of metal powder while the tip die 402 rotates, or after rotation, may form the tip insert segment 314 with a density gradient along the axial length of the tip insert segment 314, wherein the density of the tip insert segment 314 near the rear interface end 326 is lower than the density near the tip end 324.

[0023] Fig. 4E illustrates the tip insert segment 314 formed by the tip press assembly 400. As illustrated, the tip insert segment 314 has a hollow cone shape. Further, as previously mentioned, the tip insert segment 314 may have a density gradient along its axial length. In particular, the density of the tip insert segment 314 may decrease in the direction from the tip end 324 to the rear interface end 326. However, in some embodiments, the tip press assembly 400 may be inverted vertically so that the propulsion of the metal powder over the tip die 402 may drive lower density metal powder toward the tip end 324 of the tip insert segment 314. In such an embodiment, the tip insert segment 314 may have a density gradient, with the density decreasing in the direction from the rear interface end 326 to the tip end 324.

[0024] The Fig. 5A-5E illustrate various views of a base press assembly 500 forming a base liner segment 320 for the segmented shaped charge liner 302 according to some embodiments of the present disclosure. In general, a variety of press assemblies having respective presses and dies may be used to form the segmented shaped charge liner 302. For example, the variety of press assemblies may include the tip press assembly 400 described above, a first intermediate press assembly, a second intermediate press assembly, and the illustrated base press assembly 500. However, any suitable press assemblies may be used to form the variety of liner segments 312 for the segmented shaped charge liner 302.As stated above, the tip press assembly 400 may include the conical tip die 402 configured to receive the corresponding conical tip punch 404 to form the tip insert segment 314 having a hollow conical shape. Further, the first intermediate press assembly may include a first frustoconical intermediate die configured to receive a first frustoconical intermediate punch to form a first intermediate insert segment 316 having a hollow frustoconical shape. The second intermediate press assembly may include a second frustoconical intermediate die configured to receive a second frustoconical intermediate punch to form a second intermediate insert segment 318 having a hollow frustoconical shape.Additionally, as illustrated, the base press assembly 500 may include a frustoconical base die 502 configured to receive a frustoconical base punch 504 to form the bottom liner segment 320 having a hollow frustoconical shape. Each of the press assemblies may be configured to form a respective liner segment from the plurality of liner segments 312 configured to be stacked within the shaped charge casing 300 to form the segmented shaped charge liner 302.

[0025] Fig. 5A illustrates a cross-sectional view of a base press assembly 500 for forming the base insert segment 320. As illustrated, the base press assembly 500 includes the base die 502 and the base punch 504. The base die 502 may be a frustoconical tip die 402 configured to receive a corresponding frustoconical base punch 504 to form the base insert segment 320 with a hollow frustoconical shape. In the illustrated embodiment, the base die 502 is oriented such that the diameter of an inner base wall 506 of the base die 502 increases in the upward direction 408. That is, the inner base wall 506 of the base die 502 may be angled with respect to a central axis 508 of the base die 502 such that the base die 502 may form the base insert segment 320 having a hollow frustoconical shape.

[0026] Fig. 5B illustrates the base press assembly 500 after receiving the third group 356 of metal powder according to some embodiments of the present disclosure. As illustrated, the base die 502 (e.g., a frustoconical base die) is configured to receive the third group 356 of metal powder. A desired amount of the third group 356 of metal powder may be introduced into the base die 502. As set forth above, the third group 356 of metal powder may comprise a metal or metal alloy powder selected from the group consisting of iron, steels, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, alloys thereof, and combinations thereof. Further, the third group 356 of metal powder may settle near a bottom 510 of the base die 502.

[0027] Fig. 5C illustrates the base press assembly 500 with a rotating base die 502, according to some embodiments of the present disclosure. The base die 502 may include a base die portion 512 rotatably housed within a base outer housing 514. That is, the base die portion 512 may be configured to rotate within the base outer housing 514 about the central axis 508 of the base die 502. Additionally, the base die 502 may include a base actuator configured to drive rotation of the base die portion 512 relative to the base outer housing 514. By rotating the base die portion 512, the third group 356 of metal powder may be propelled outward and upward by centrifugal force on the inner base wall 506 of the base die portion 512 of the base die 502.As the third group 356 of metal powder is forced outward and upward by centrifugal force on the inner base wall 506, the metal particles of the third group 356 of metal powder can be separated according to their density. In particular, particles with a lower density can be forced toward an upper end 516 of the inner base wall 506.

[0028] Fig. 50 illustrates the base press assembly 500 with the base punch 504 compressing the third group 356 of metal powder against the base die 502 according to some embodiments of the present disclosure. Indeed, the base punch 504 (e.g., a frustoconical base punch) is configured to compress the third group 356 of metal powder against the inner base wall 506 of the base die 502 (e.g., a frustoconical base die) to compact the third group 356 of metal powder and form the base insert segment 320 having a hollow frustoconical shape. As stated above, the third group 356 of compacted metal powder may be in a green state. That is, the third group 356 of metal powder may be compacted into the desired hollow frustoconical shape, but not sintered or otherwise fused into a solid insert segment.Furthermore, the base punch 504 may be configured to compress the third group 356 of metal powder against the inner base wall 506 during or after rotation of the base die 502, such that the higher-density particles of the third group 356 of metal powder are located near the upper end 516 of the inner base wall 506. Compressing the third group 356 of metal powder during or after rotation of the base die 502 may form the base insert segment 320 with a density gradient along the axial length of the base insert segment 320, wherein the density of the base insert segment 320 near the rear base end 358 is lower than the density near the front base interface end 352.

[0029] Fig. 5E illustrates the base insert segment 320 formed by the base press assembly 500. As illustrated, the base insert segment 320 has a hollow frustoconical shape. Further, as stated above, the base insert segment 320 may have a density gradient along its axial length. In particular, the density of the base insert segment 320 may increase in the direction from the front base interface end 352 to the rear base end 358. However, in some embodiments, the base press assembly 500 may be inverted vertically so that projecting the third group 356 of metal powder over the base die assembly 502 may drive higher density metal powder toward the front base interface end 352 of a base insert segment 320 formed by the base die 502.In such an embodiment, the base liner segment 320 may have a density gradient, with the density decreasing in the direction from the rear base end 358 to the front base interface end 352.

[0030] Fig. 6 illustrates a cross-sectional view of the shaped charge 120 having a plurality of liner segments 312 with interface features according to some embodiments of the present disclosure. As stated above, the plurality of liner segments 312 may be configured to be stacked within the shaped charge casing 300 to form a hollow conical liner. Indeed, a method of forming the segmented liner may include the step of stacking the individual liner segments 312 within the shaped charge casing 300. In the illustrated embodiment, the first intermediate liner segment 316 is stacked upon the tip liner segment 314 with the forward first intermediate interface end 342 joined to the rearward interface end 326 of the tip liner segment 314.Further, the second intermediate liner segment 318 is stacked onto the first intermediate liner segment 316 with the front second intermediate interface end 348 joined to the rear first intermediate interface end 346, and the base liner segment 320 is stacked onto the second intermediate liner segment 318 with the front base interface end 352 joined to the rear second intermediate interface end 350.

[0031] Furthermore, as illustrated, each liner segment of the plurality of liner segments 312 includes at least one interface feature 600 configured to cooperate with a corresponding interface feature of an adjacent liner segment in the shaped charge casing 300 to prevent at least lateral movement between the liner segment and the adjacent liner segment. The at least one interface feature 600 of each liner segment 312 may include a protrusion, a recess, or a combination thereof. For example, the rear second intermediate interface end 350 of the second intermediate liner segment 318 may include a protrusion 602 (e.g., a rib) extending from a surface of the rear second intermediate interface end 350 and across at least a portion of the perimeter of the rear second intermediate interface end 350.Further, the front base interface end 352 of the base liner segment 320 may include a corresponding recess 604 (e.g., a channel) extending into a surface of the front base interface end 352 and around at least a portion of the perimeter of the front base interface end 352. Upon stacking the base liner segment 320 onto the second intermediate liner segment 318, the protrusion 602 of the second intermediate liner segment 318 may extend into the recess 604 of the base liner segment 320. Such interface features 600 may at least partially restrict lateral movement between the second intermediate liner segment 318 and the base liner segment 320.

[0032] Furthermore, as set forth above, each liner segment of the plurality of liner segments 312 may have a density gradient along an axial length of the liner segment. Each liner segment may have a leading end (e.g., tip end 324, leading first intermediate interface end 342, etc.) and a trailing end (e.g., trailing interface end 326, trailing first intermediate interface end 346, etc.). Generally, the trailing end has a larger diameter than the leading end. The density gradient for each liner segment may have a first average density between 0.3613 and 0.7948 pounds per cubic inch [e.g., between 10.0 and 22.0 grams / cubic centimeter (g / cm 3)] at the leading end of each insert segment and a second intermediate density at the trailing end of each insert segment. The second intermediate density may be between 95 and 99 percent of the density of the first intermediate density. For example, the density gradient for an insert segment may include the first intermediate density of 10.0 g / cm 3 at the front end and the second average density of 9.5 g / cm 3 at the rear end. Alternatively, the plurality of insert segments may be inverted such that the first average density is between 95 and 100 percent of the density of the second average density. The density gradient along the axial length of the insert segments 312 may include a gradual transition from the first average density to the second average density.

[0033] The Fig. 7A-7B illustrate cross-sectional views of a secondary press assembly 700 configured to press a plurality of liner segments 312 into a continuous liner according to some embodiments of the present disclosure. In some embodiments, the plurality of liner segments 312 may be pressed into a single continuous liner 702 prior to insertion into the shaped charge casing. Referring to Fig. 7A, the plurality of insert segments 312 may be stacked in a secondary conical die 704 of the secondary press assembly 700 such that the stacked insert segments 312 form a hollow conical shape. For example, the tip insert segment 314 may be inserted near a bottom 706 of the secondary conical die 704, the first intermediate insert segment 316 may be stacked on the tip insert segment 314, the second intermediate insert segment 318 may be stacked on the first intermediate insert segment 316, and the base insert segment 320 may be stacked on the second intermediate insert segment 318. Referring to Fig. 7B, the secondary press includes a secondary conical punch 708. The plurality of liner segments 312 can be assembled or pressed into the continuous liner 702 by inserting the secondary conical punch 708 into the secondary conical die 704. In particular, the secondary conical punch 708 can compress the plurality of liner segments 312 into each other and into the secondary conical die 704, so that the plurality of liner segments 312 fuse into a single continuous liner 702, which can then be inserted into the shaped charge casing 300.

[0034] Fig.8 illustrates a cross-sectional view of the continuous liner 702 disposed within the shaped charge 120, according to some embodiments of the present disclosure. As illustrated, the continuous liner 702 may have a hollow cone shape formed from a plurality of liner segments 312. Thus, the continuous liner 702 may have a density gradient based at least in part on the respective density gradients, axial lengths, etc., of the liner segments 312. For example, the density of the continuous liner 702 may increase from a tip end 800 of the continuous liner 702 in a direction toward a base end 802 of the continuous liner 702. However, the density may decrease in a second portion 804 of the continuous liner 702 formed from the first intermediate liner segment 316. The density may then increase in the direction toward a third portion 806 of the endless insert 702 formed from the second intermediate insert segment 318.The continuous liner 702 may retain the density gradients of the plurality of liner segments 312 from which it was formed, so that the continuous liner 702 may be formed with specific properties for perforating a target material in the borehole.

[0035] Accordingly, the present disclosure may provide segmented shaped charges and methods for forming segmented shaped charges used in downhole perforation gun systems for perforating materials in the downhole. These systems and methods may incorporate any of the various features disclosed herein, including one or more of the following.

[0036] Statement 1. A shaped charge liner comprising: a plurality of liner segments for a shaped charge configured to perforate a sidewall of a borehole upon detonation, the plurality of liner segments comprising: a tip liner segment comprising a first group of compacted metal powder having a hollow cone shape with a rear interface end disposed opposite a tip end, the rear interface end having a larger diameter than the tip end, and the tip liner segment configured to be disposed within a shaped charge casing of the shaped charge;and a base liner segment comprising a second group of compacted metal powder having a hollow frustoconical shape with a rear base end disposed opposite a front base interface end, the rear base end having a larger diameter than the front base interface end, and the base liner segment configured to be disposed at least partially within the shaped charge casing;

[0037] Statement 2. The shaped charge liner of Statement 1, wherein the plurality of liner segments are configured to be stacked within the shaped charge casing to form a hollow cone shape.

[0038] Statement 3. The shaped charge liner of Statement 1 or Statement 2, wherein each liner segment of the plurality of liner segments comprises at least one interface feature configured to cooperate with a corresponding interface feature of an adjacent liner segment in the shaped charge casing to prevent at least lateral movement between the liner segment and the adjacent liner segment.

[0039] Statement 4. The shaped charge liner of any preceding statement, wherein the at least one interface feature of each liner segment comprises a protrusion, a recess, or a combination thereof.

[0040] Statement 5. The shaped charge liner of any preceding statement, wherein each liner segment of the plurality of liner segments has a density gradient along an axial length of the liner segment.

[0041] Statement 6. The shaped charge liner of any preceding statement, wherein the density gradient has a first average density of between about 10 g / cm 3 up to about 22 g / cm 3 at a front end of each insert segment of the plurality of insert segments and a second average density at a rear end of each insert segment of the plurality of insert segments, wherein the second average density is between about 95 percent to about 99 percent of the first average density, and wherein the rear end has a larger diameter than the front end.

[0042] Statement 7. The shaped charge liner of any preceding statement, wherein an axial length of each liner segment is between about 12 percent and about 50 percent of a combined axial length of the plurality of liner segments.

[0043] Statement 8. The shaped charge liner of any preceding statement, wherein a thickness of each liner segment is between about 0.035 inches and about 0.11 inches.

[0044] Statement 9. The shaped charge liner of any preceding statement, wherein the first group of compacted metal powder and the second group of compacted metal powder each comprise at least one metal or at least one metal alloy powder selected from the group consisting of iron, steel, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, an alloy thereof, and combinations thereof.

[0045] Statement 10. The shaped charge liner of any preceding statement, wherein the plurality of liner segments further comprises at least one intermediate liner segment configured to be disposed between the tip liner segment and the base liner segment in the shaped charge casing, and wherein the tip liner segment, the intermediate liner segment, and the base liner segment are configured to be stacked in the shaped charge casing to form a hollow cone shape.

[0046] Statement 11. The shaped charge liner of any preceding statement, wherein the at least one intermediate liner segment comprises a first intermediate liner segment and a second intermediate liner segment, wherein the first intermediate liner segment is disposed adjacent the tip liner segment and wherein the second intermediate liner segment is disposed adjacent the base liner segment.

[0047] Statement 12. A method of making a segmented shaped charge liner, comprising: introducing a respective group of metal powder into each die of a plurality of dies; rotating each die of a plurality of dies to propel the respective groups of metal powder outwardly and upwardly by centrifugal force on the respective inner walls of the plurality of dies; and pressing a respective punch into each die of a plurality of dies to compact the respective groups of metal powder and form respective liner segments, the liner segments being configured to be stacked within a shaped charge casing of a shaped charge configured to perforate a sidewall of a borehole upon detonation.

[0048] Statement 13. The method of Statement 12, wherein the plurality of dies comprises a conical die configured to receive a corresponding conical punch for forming a tip insert segment having a hollow conical shape, and wherein the plurality of dies further comprises at least one frustoconical die configured to receive a corresponding frustoconical punch for forming at least one insert segment having a hollow frustoconical shape.

[0049] Statement 14. The method of Statement 12 or Statement 13, wherein the plurality of dies comprises: a conical die configured to receive a corresponding conical punch for forming a tip liner segment having a hollow conical shape; a first frustoconical die configured to receive a first frustoconical punch for forming a first intermediate liner segment having a hollow frustoconical shape, wherein the first intermediate liner segment has a larger average diameter than the intermediate liner segment; a second frustoconical die configured to receive a second frustoconical punch for forming a second intermediate liner segment having a hollow frustoconical shape, wherein the second intermediate liner segment has a larger average diameter than the first intermediate liner segment;and a third frustoconical die configured to receive a third frustoconical punch for forming a base insert segment having a hollow frustoconical shape, the base insert segment having a larger average diameter than the second intermediate insert segment;

[0050] Statement 15. The method of any of statements 12-14, further comprising the step of stacking the liner segments within the shaped charge casing to form a hollow conical liner at least partially disposed within the shaped charge casing.

[0051] Statement 16. The method of any of statements 12-14, further comprising the steps of: stacking the liner segments within a secondary conical die such that the stacked liner segments form a hollow cone shape; and pressing a secondary conical punch into the secondary conical die to fuse the liner segments into a continuous liner configured to be disposed within a shaped charge casing.

[0052] Statement 17. The method of any one of statements 12-16, wherein rotating each die of a plurality of dies to propel the respective groups of metal powder radially outward and vertically upward by centrifugal force on the corresponding inner walls of the plurality of dies separates the metal particles of the respective groups of metal powder according to their density such that the insert segments have a density gradient along an axial length of each respective insert segment.

[0053] Statement 18. The method of any one of statements 12-18, wherein each die of the plurality of dies is oriented such that the respective diameters of the corresponding inner walls of the plurality of dies increase in the upward direction.

[0054] Statement 19. A system for manufacturing a segmented shaped charge liner, comprising: a first press assembly including a conical punch and a conical die, the conical die configured to receive a first group of metal powder, and the conical punch configured to press the first group of metal powder against a first inner wall of the conical die to densify the first group of metal powder and form a tip liner segment having a hollow conical shape;and a second press assembly comprising a frustoconical punch and a frustoconical die, the frustoconical die being configured to receive a second group of metal powder, and the frustoconical punch being configured to press the second group of metal powder against a second inner wall of the frustoconical die to compact the second group of metal powder and form a base liner segment having a hollow frustoconical shape, the tip liner segment and the base liner segment being configured to be disposed within a shaped charge casing of a shaped charge configured to perforate a sidewall of a borehole upon detonation;

[0055] Statement 20. The system of Statement 19, further comprising a secondary press assembly comprising a secondary conical punch and a secondary conical die, the secondary conical die configured to receive the tip liner segment and the base liner segment, and the secondary conical punch configured to compress the tip liner segment and the base liner segment against a third interior wall of the secondary conical die and against each other to form a continuous liner having a hollow cone shape configured to be disposed within a shaped charge casing of a shaped charge configured to perforate a sidewall of a wellbore upon detonation.

[0056] Therefore, the present embodiments are well adapted to achieve the stated objects and advantages as well as those inherent therein. The particular embodiments disclosed above are merely illustrative, as the present embodiments may be modified and practiced in different but equivalent ways as will be apparent to those skilled in the art having the benefit of the teachings contained herein. Although individual embodiments are discussed, all combinations of each embodiment are contemplated and covered by the disclosure. Furthermore, no limitations on the details of construction or workmanship shown herein are intended except as described in the following claims. In addition, the terms in the claims have their simple, ordinary meaning unless explicitly and clearly defined otherwise by the patentee.It will therefore be apparent that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the present disclosure.

Claims

[1] Shaped charge liner, comprising: a plurality of liner segments for a shaped charge configured to perforate a sidewall of a borehole upon detonation, the plurality of liner segments comprising: a tip insert segment comprising a first group of compacted metal powder having a hollow cone shape with a rear interface end disposed opposite a tip end, the rear interface end having a larger diameter than the tip end, and the tip insert segment being configured to be disposed within a shaped charge casing of the shaped charge; and a base liner segment comprising a second group of compacted metal powder having a hollow frustoconical shape with a rear base end disposed opposite a front base interface end, the rear base end having a larger diameter than the front base interface end, and the base liner segment configured to be disposed at least partially within the shaped charge casing. [2] The shaped charge liner of claim 1, wherein the plurality of liner segments are configured to be stacked within the shaped charge casing to form a hollow cone shape. [3] The shaped charge liner of claim 1, wherein each liner segment of the plurality of liner segments comprises at least one interface feature configured to cooperate with a corresponding interface feature of an adjacent liner segment in the shaped charge casing to prevent at least lateral movement between the liner segment and the adjacent liner segment. [4] The shaped charge liner of claim 3, wherein the at least one interface feature of each liner segment comprises a protrusion, a recess, or a combination thereof. [5] The shaped charge liner of claim 1, wherein each liner segment of the plurality of liner segments has a density gradient along an axial length of the liner segment. [6] A shaped charge liner according to claim 5, wherein the density gradient has a first average density between about 10 g / cm 3 up to about 22 g / cm 3at a front end of each insert segment of the plurality of insert segments and a second average density at a rear end of each insert segment of the plurality of insert segments, wherein the second average density is between about 95 percent to about 99 percent of the first average density, and wherein the rear end has a larger diameter than the front end. [7] The shaped charge liner of claim 1, wherein an axial length of each liner segment is between about 12 percent and about 50 percent of a combined axial length of the plurality of liner segments. [8] The shaped charge liner of claim 1, wherein a thickness of each liner segment is between about 0.035 inches and about 0.11 inches. [9] The shaped charge liner of claim 1, wherein the first group of compacted metal powder and the second group of compacted metal powder each comprise at least one metal or at least one metal alloy powder selected from the group consisting of iron, steel, copper, brass, bronze, manganese, molybdenum, nickel, tungsten, bismuth, tin, lead, tantalum, aluminum, an alloy thereof, and combinations thereof. [10] The shaped charge liner of claim 1, wherein the plurality of liner segments further comprises at least one intermediate liner segment configured to be disposed between the tip liner segment and the base liner segment in the shaped charge casing, and wherein the tip liner segment, the intermediate liner segment, and the base liner segment are configured to be stacked in the shaped charge casing to form a hollow cone shape. [11] A shaped charge liner according to claim 10, wherein the at least one intermediate liner segment comprises a first intermediate liner segment and a second intermediate liner segment, wherein the first intermediate liner segment is arranged adjacent to the tip liner segment and wherein the second intermediate liner segment is arranged adjacent to the base liner segment. [12] A method for producing a segmented shaped charge liner, comprising: introducing a respective group of metal powder into each die of a plurality of dies; Rotating each die of a plurality of dies to drive the respective groups of metal powder outwardly and upwardly by centrifugal force on the corresponding inner walls of the plurality of dies; and Pressing a respective punch into each die of a plurality of dies to compact the respective groups of metal powder and form corresponding liner segments, the liner segments being configured to be stacked within a shaped charge casing of a shaped charge configured to perforate a sidewall of a borehole upon detonation. [13] The method of claim 12, wherein the plurality of dies comprises a conical die configured to receive a corresponding conical punch for forming a tip insert segment having a hollow conical shape, and wherein the plurality of dies further comprises at least one frustoconical die configured to receive a corresponding frustoconical punch for forming at least one insert segment having a hollow frustoconical shape. [14] The method of claim 12, wherein the plurality of matrices comprises: a conical die configured to receive a corresponding conical punch for forming a tip insert segment having a hollow conical shape; a first frustoconical die configured to receive a first frustoconical punch for forming a first intermediate liner segment having a hollow frustoconical shape, the first intermediate liner segment having a larger average diameter than the intermediate liner segment; a second frustoconical die configured to receive a second frustoconical punch for forming a second intermediate liner segment having a hollow frustoconical shape, the second intermediate liner segment having a larger average diameter than the first intermediate liner segment; and a third frustoconical die configured to receive a third frustoconical punch for forming a base insert segment having a hollow frustoconical shape, the base insert segment having a larger average diameter than the second intermediate insert segment. [15] The method of claim 12, further comprising the step of stacking the liner segments in the shaped charge casing to form a hollow conical liner at least partially disposed within the shaped charge casing. [16] The method of claim 12, further comprising the following steps: Stacking the insert segments within a secondary conical die such that the stacked insert segments form a hollow cone shape; and Pressing a secondary conical punch into the secondary conical die to fuse the liner segments into a continuous liner configured to be disposed in a shaped charge casing. [17] The method of claim 12, wherein rotating each die of a plurality of dies to drive the respective groups of metal powder radially outward and vertically upward by centrifugal force on the corresponding inner walls of the plurality of dies separates the metal particles of the respective groups of metal powder according to their density such that the insert segments have a density gradient along an axial length of each respective insert segment. [18] The method of claim 12, wherein each die of the plurality of dies is oriented such that the respective diameters of the corresponding inner walls of the plurality of dies increase in the upward direction. [19] System for producing a segmented shaped charge liner, comprising: a first press assembly comprising a conical punch and a conical die, the conical die being configured to receive a first group of metal powder, and the conical punch being configured to press the first group of metal powder against a first inner wall of the conical die to compact the first group of metal powder and form a tip insert segment having a hollow conical shape; and a second press assembly comprising a frustoconical punch and a frustoconical die, the frustoconical die being configured to receive a second group of metal powder, and the frustoconical punch being configured to press the second group of metal powder against a second inner wall of the frustoconical die to densify the second group of metal powder and form a base liner segment having a hollow frustoconical shape, the tip liner segment and the base liner segment being configured to be disposed within a shaped charge casing of a shaped charge configured to perforate a sidewall of a borehole upon detonation. [20] The system of claim 19, further comprising a secondary press assembly comprising a secondary conical punch and a secondary conical die, the secondary conical die being configured to receive the tip liner segment and the base liner segment, and the secondary conical punch being configured to compress the tip liner segment and the base liner segment against a third inner wall of the secondary conical die and against each other to form a continuous liner having a hollow cone shape configured to be disposed within a shaped charge casing of a shaped charge configured to perforate a sidewall of a wellbore upon detonation.

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