Patent Publication Number: US-11655692-B2

Title: Shaped charge orientation

Description:
BACKGROUND 
     After drilling a wellbore in a subterranean formation for recovering hydrocarbons such as oil and gas lying beneath the surface, a casing string may be fed into the wellbore. Generally, the casing string protects the wellbore from failure (e.g., collapse, erosion) and provides a fluid path for hydrocarbons during production. Traditionally the casing string is cemented to the wellbore. To access the hydrocarbons for production, a perforating gun system may be deployed into the casing string via a tool string. The tool string (e.g., a tubing string, wireline, slick line, coil tubing) lowers the perforating gun system into the casing string to a desired position within the wellbore. Once the perforating gun system is in position such that shaped charges are disposed adjacent to a subterranean formation having hydrocarbons, the shaped charges are detonated. The detonation perforates the casing string, the cement, and the subterranean formation such that hydrocarbons may flow into the casing string via the perforations. 
     In some cases, operators are interested in perforating wells with phased shots where all shaped charges are pointed toward a predetermined orientation of a horizontal or inclined well. Typically, this may be achieved with externally adjustable lock rings on the perforating carrier or connecting tandems, or with internally weighted charge tubes that are mounted on bearings. However, these techniques may have their disadvantages. For example, in weighted/bearing systems, re-positioning and/or adjusting the shaped charges to modify the orientations of the shaped charges within the wellbore after initial installation may require disassembly of the perforating guns. That is, the rotating members and other perforating gun components must be removed from the perforating gun bodies to provide access to re-position and/or adjust the shaped charge holders, replace the rotating member, etc. Unfortunately, removing rotating members and other perforating gun components to adjust the orientations of the shaped charges is costly, time consuming, and may hinder efficiency of perforation operations. 
     In some cases, operators are interested in perforating wells with phased shots where all shaped charges are pointed toward a predetermined orientation of a horizontal or inclined well. Typically, this may be achieved with externally adjustable lock rings on the perforating carrier or connecting tandems, or with internally weighted charge tubes that are mounted on bearings. 
     However, these techniques may have their disadvantages. For example, in weighted/bearing systems, re-positioning and/or adjusting the shaped charges to modify the orientations of the shaped charges after initial installation of the charge tube may require disassembly of the perforating guns. That is, the rotating members and other perforating gun components must be removed from the perforating gun bodies to provide access to re-position and/or adjust the shaped charge holders, replace the rotating member, etc. Unfortunately, removing rotating members and other perforating gun components to adjust the orientations of the shaped charges is costly, time consuming, and may hinder efficiency of perforation operations. 
     The external lock ring systems may only need the carrier to be rotated and the charges may stay aligned with scallops on the perforating gun. However, the external lock rings require that all of the carriers are aligned and remain aligned during tightening of the lock rings. Further, wrenches are required to hold the carriers in place during tightening of the lock rings to prevent backing off of the carriers during torquing. Some systems also require a set screw to be tightened to keep the lock ring from backing off. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These drawings illustrate certain aspects of some of the examples of the present disclosure and should not be used to limit or define the method. 
         FIG.  1    illustrates an operational environment, in accordance with examples of the present disclosure; 
         FIG.  2    illustrates a close-up view of a perforating gun system, in accordance with examples of the present disclosure; 
         FIGS.  3 A and  3 B  illustrate close-up views of a perforating gun alignment assembly, in accordance with examples of the present disclosure; 
         FIG.  4 A  illustrates a close-up view of a spring-loaded electrical contact, in accordance with examples of the present disclosure; 
         FIG.  4 B  illustrates a close-up view of an electrical contact without a spring, in accordance with examples of the present disclosure; 
         FIG.  5    illustrates a ratcheting mechanism for orienting the charge tube, in accordance with examples of the present disclosure; and 
         FIG.  6    illustrates an operative sequence for orienting a charge tube of the perforating gun system, in accordance with examples of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Provided are systems and methods for adjusting a perforating assembly for subterranean operations. Particularly, the systems and methods are directed to an adjustable end alignment assembly that may attach to the shaped charge holder/tube inside the perforating gun body/carrier, to allow a field crew to dial-in/set the orientation of the shaped charges as desired. 
     In some examples, the end alignment assembly may include two components that nest/interlock together at an end of the charge tube and the gun carrier. A first component may be coupled to the charge tube and a second component may be disposed within the gun carrier. The first component may be disposed concentrically or eccentrically within the second component, and each component may be of a tubular or circular shape to allow rotation of the first component within the second component. Additionally, each component may include a section to allow the charge tube to be adjusted/rotated to the desired orientation, without bearings and lock rings. For example, the first component may include a section with teeth, for example, in the form of a spline feature along an external circumference, and the second component may include a second spline feature along an internal circumference to allow nesting of the first component within the second component. Also, in some examples, a ratcheting mechanism may be employed to ratchet/rotate the charge tube as desired. 
     In some examples, an electrical contact may secure the first and second components. The electrical contact may pass through both components and may include a portion/feature (e.g., a groove) for receiving a fastener. Non-limiting examples of the fastener include a retaining clip, a retaining nut, or a hole and pin, among others. The fastener may be disposed on the electrical contact to secure the first and second components. The electrical contact may also include a feature for attaching a wire (e.g., a tubular extension) to communicate with other perforating guns. 
     In particular examples, the first and second components may be nested together before the charge tube is inserted into the carrier. A spring feature may urge the components together and prevent the charge tube from moving until desired. The spring feature may also prevent the first and second components from falling out of the carrier. The electrical contact may include a spring. 
     For example, the charge tube may be pulled slightly to separate the first component from the second component. The charge tube may then be turned to the desired orientation and the spring pulls or otherwise urges the components back together in the nested configuration. With the next/adjacent perforating gun attached, the charge tube may no longer be adjusted. Thus, as part of the rotation technique, in some examples, an outer section of the gun carrier may be marked (e.g., via a paint pen) to indicate an orientation of the shaped charges (e.g., the direction the charges are facing). 
     In other examples, the second component may be disposed within the carrier before inserting the charge tube, such that the charge tube may not be secured within the carrier until attachment of the next perforating gun. 
     In some examples, the alignment assembly may be constructed from injection-molded plastic with an electrical contact made of any suitable conductive material such as brass, for example. In other examples, the alignment assembly may be made of metal and the electrical contact is insulated. 
       FIG.  1    illustrates an operational environment  100 , in accordance with examples of the present disclosure. It should be noted that while  FIG.  1    generally depicts a land-based drilling and completion assembly, those skilled in the art will readily recognize that the principles described herein are equally applicable to subsea drilling and completion operations that employ floating or sea-based platforms and rigs, without departing from the scope of the disclosure. 
     As illustrated, the operational environment  100  includes a platform  102  that supports a derrick  104  having a traveling block  106  for raising and lowering a tool string  108 . The tool string  108  includes, but is not limited to, a work string  110 , a perforating gun system  112 , and any other suitable tools, as generally known to those skilled in the art. While not shown, tubing string, wireline, slick line, and/or coil tubing may be used instead of the work string  110  for supporting the perforating gun system  112 . 
     The work string  110  is configured to lower the perforating gun system  112  into a wellbore  114 . As illustrated, the wellbore  114  may be lined with 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 work string  110  lowers the perforating gun system  112  to a position such that shaped charges  120  are disposed adjacent to a subterranean formation  122  having the hydrocarbons, and the perforating gun system  112  detonates the shaped charges  120 . 
     In some examples, the shaped charges  120  may be sequentially detonated by the perforating gun system  112  in a downhole to up-hole direction  124  or an up-hole to downhole direction  126 . The detonations perforate the casing  116 , the cementing, and the subterranean formation  122  in the respective paths of the shaped charge detonations such that hydrocarbons may flow into the casing  116  string via the perforations. 
     The wellbore  114  has a vertical portion  128  and a horizontal portion  130  with the perforating gun system  112  being disposed in the horizontal portion  130 . In some examples, the perforating gun system  112  may be disposed in the vertical portion  128 . The perforating gun system  112  includes a charge tube  132  (e.g., a rotating member holding the shaped charges  120 ) rotatably mounted within a gun body  134  of the perforating gun system  112 . The rotation may be relative to a longitudinal axis  140  of the perforating gun system  112 . 
     In particular examples, the perforating gun system  112  may include an adjustable end alignment assembly  136  (“alignment assembly  136 ”). The alignment assembly  136  may be disposed within the gun body  134  at an end  138  (e.g., proximal end) or an end  139  (e.g., distal end). 
       FIG.  2    illustrates a close-up view of the perforating gun system  112 , in accordance with examples of the present disclosure. As set forth above, the perforating gun system  112  includes the gun body  134  (e.g., a gun carrier). The gun body  134  is configured to house the charge tube  132 . In the illustrated example, the charge tube  132  includes a generally cylindrical shape. However, the charge tube  132  may include any suitable shape that permits rotation of the charge tube  132  within an interior portion  200  of the gun body  134 . For example, the charge tube  132  may include an elliptical profile so long as the charge tube  132  may rotate within the gun body  134  without contacting an interior surface  202  of the gun body  134 . Contact between the charge tube  132  and gun body  134  may hinder or prevent rotation of the charge tube  132 . 
     The alignment assembly  136  may be disposed within the gun body  134  at the end  138  (e.g., proximal end) or the end  139  (e.g., distal end). The alignment assembly  136  may be attached to the charge tube  132  and the gun body  134 . The perforating gun system  112  also includes the at least one shaped charge  120 . As set forth above, the shaped charge  120  may be disposed within the charge tube  132 . A wire  204  may be disposed within the charge tube  132  to allow communication between a series of perforating guns. The wire  204  may be in communication with an electrical contact  206  of the alignment assembly  136 . 
       FIGS.  3 A and  3 B  illustrate close-up views of the alignment assembly  136 , in accordance with examples of the present disclosure. In some examples, the alignment assembly  136  may include two components  300  and  302  that may nest/interlock together. In some examples, the two components  300  and  302  may be constructed from injection-molded plastic. In other examples, the components  300  and  302  may be made of metal, however, the electrical contact  206  may be insulated. 
     A first component  300  may be coupled to the charge tube  132  and a second component  302  may be disposed within the gun body  134 . In some examples, the first component  300  may be coupled to the charge tube  132  via a fastener (e.g., a screw) disposed through one or more apertures  303  of the first component  300 . In some examples, the apertures  303  may be disposed on opposite sides of the alignment assembly  136 . The second component  302  may be disposed within the gun body  134 , for example, such that the second component  302  does not rotate. Rotation may be prevented with any suitable feature such as a ridge  305 , for example. The first component  300  may be disposed concentrically or eccentrically within the second component  302 , and each component may be of a tubular or circular shape to allow rotation of the first component  300  within the second component  302 . Each of the first component  300  and the second component  302  may include a section with a mating surface, such as teeth, for example, to allow the charge tube  132  to be adjusted/rotated to the desired orientation, without bearings and lock rings. In some examples, the charge tube  132  may be segmented rather than a continuous tube. 
     For example, as best shown on  FIG.  3 B , the first component  300  may include a section  304  with teeth  306  in the form of a spline. The teeth  306  may be disposed along an external circumference of the section  304 . The first component  300  may also include a cap  308  with a passage  310 . The passage  310  may extend through a center of the cap  308  along a longitudinal axis L. The teeth  306  and spacing therebetween may be of any suitable profile, shape, and/or size. 
     The second component  302  may include a section  312  with teeth  314  disposed along an internal circumference in the form of a spline, for example, to allow nesting of the first component  300  within the second component  302 . The teeth  314  and spacing therebetween may be of any suitable profile, shape, and/or size. 
     A protrusion  316  may extend from a base  318  forming a cavity  320  between the teeth  314  and the protrusion  316 . The protrusion  316  may include a passage  317  also extending in a direction of L. The passage  317  may be coaxially aligned with the passage  310  to receive the electrical contact  206 . For example, the first component  300  may receive the protrusion  316  within the cap  308  such that the teeth  306  and  314  are nested together such that the electrical contact  206  is disposed at centers of both the first component  300  and the second component  302  via the passages  310  and  317 . In some examples, a fastener  325  may secure the electrical contact  206  within the alignment assembly  136 , as best shown on  FIG.  3 A . Non-limiting examples of the fastener  325  may include a retaining clip, a retaining nut, and/or a hole and pin, among others. 
     Additionally, in some examples, the electrical contact  206  may be spring-loaded to urge the first component  300  and the second component  302  together. For example, the charge tube  132  may be pulled slightly (indicated by directional arrow  328 ) to separate the first component  300  from the second component  302 . The charge tube  132  may then be rotated clockwise (indicated by directional arrow  329 ) or counterclockwise (indicated by directional arrow  330 ) to the desired orientation. An axis of rotation may extend along L. After orienting the charge tube  132 , the spring may pull or otherwise urge the components  300  and  302  back together in the nested/interlocked configuration. With a next/adjacent perforating gun attached, the charge tube  132  may no longer be adjusted. Thus, as part of the rotation technique, in some examples, an outer section of the gun body  134  may be marked (e.g., via a paint pen) to indicate an orientation of the shaped charges  120  (e.g., the direction the shaped charges  120  are facing). 
     In particular examples, as best shown on  FIG.  3 A , each of components  300  and  302  may include slots such as slots  332  and  334  to facilitate installation or removal of the electrical contact  206 , when aligned. In some examples, the slots  332  and  334  extend radially from a center of each of the components. 
       FIG.  4 A  illustrates a close-up view of the electrical contact  206 , in accordance with examples of the present disclosure. As previously noted, the electrical contact  206  may include a head  400 . The head  400  may be of any suitable shape, such as, for example, circular or tubular. An elongated portion  402  may extend from the head  400 . A diameter of the head  400  may be greater than a diameter of the elongated portion  402 . The elongated portion  400  may include a portion  404  (e.g., a groove) at a distal end of the elongated portion  402  to receive the fastener  325  to secure the electrical contact  206  within the spline features of the alignment assembly  136  (e.g., shown on  FIG.  3 A ). 
     The electrical contact  206  may also include a second elongated portion  406  extending from the elongated portion  402 . The head  400 , the elongated portion  402 , and the second elongated portion  406  may be coaxially aligned. The second elongated portion  406  may be utilized for attaching a wire. For example, a diameter and length of the second elongated portion  406  may be less than a diameter and length of the elongated portion  402  and may include a hollow portion  407  for wire accommodation. 
     In some examples, the electrical contact  206  may be spring-loaded to urge the first component  300  and the second component  302  together after orientation/rotational adjustment of the charge tube  132  (e.g., shown on  FIGS.  3 A and  3 B ). For example, the second elongated portion  406  may be movably disposed within the elongated portion  402 . A spring  408  may be disposed within the elongated portion  402  between the head  400  and the second elongated portion  406 . As, the charge tube  132  is pulled in a direction  410 , the spring  408  may compress. After, the charge tube  132  has been rotated, the spring  408  may expand in the opposite direction  412  thereby urging the first component  300  and the second component  302  together. The fastener  325  may be disposed within the portion  404  to retain the first component  300  and the second component  302  between the head  400  and the fastener  325  during rotation of the charge tube  132 . In other examples, as shown on  FIG.  4 B , the electrical contact  206  does not include the spring  408  and the elongated portion  406  is not movable. 
       FIG.  5    illustrates another example of the first component  300  and the second component  302 , in accordance with examples of the present disclosure. As illustrated, the inner section of the second component  302  includes at least one ratcheting member  500  to allow adjustment of the charge tube  132  (e.g., shown on  FIG.  3 A ) via rotation of the first component  300  either in a clockwise or counterclockwise direction. In some examples, the ratcheting member  500  may be disposed on the first component  300 . 
       FIG.  6    illustrates an operative sequence for adjusting a charge tube of a perforating gun system, in accordance with examples of the present disclosure. At step  600 : the first component  300  and the second component  302  may be secured with a fastener  325  that may be disposed on the electrical contact (e.g., best shown on  FIG.  3 A ). 
     At step  602 : the first component  300  may be attached to the charge tube  132  (e.g., via the apertures  303  shown on  FIG.  3 A ). At step  604 : the charge tube  132  may be loaded with at least one shaped charge  120  (e.g., shown on  FIGS.  3 A and  3 B ). 
     At step  606 : the charge tube  132  may be secured within the gun body  134  (e.g., via the ridge  305 ). At step  608 , a charge tube of a perforating gun system (e.g., the charge tube  132  shown on  FIGS.  3 A and  3 B ) may be moved in an axial direction to separate a first component from a second component (e.g., the first component  300  and the second component  302  shown on  FIGS.  3 A and  3 B ), wherein the electrical contact  206  passes through both components. In some examples, the second component  302  may be disposed within the gun body  134  before inserting the charge tube  132 . 
     At step  610 , the charge tube  132  may be rotated to orient the shaped charge(s)  120 . At step  612 , the charge tube  132  may be moved in an opposite direction such that the first component  300  interlocks with the second component  302 , as shown on  FIG.  3 A , for example. At step  614 : the charge tube  132  may be prevented from being adjusted by attaching another perforating gun or other connector. 
     Accordingly, the present disclosure provides systems and methods that may adjust an orientation of a charge tube for a perforation assembly, without internal weights and bearings or external lock rings. The systems and methods may include any of the various features disclosed herein, including one or more of the following statements. 
     Statement 1. An alignment system comprises a first component coupled to a charge tube, the first component operable to rotate in concert with the charge tube, wherein an axis of rotation of the first component extends in a direction of the longitudinal axis of the first component; a second component nested within the first component or disposed within a gun body, wherein the charge tube is movably disposed within the gun body; and an electrical contact extending through the first and second components, wherein the first component is further operable to move in axial directions within the gun body and along the electrical contact to interlock with the second component or separate from the second component. 
     Statement 2. The system of the statement 1, wherein the first component comprises at least one aperture operable to attach the charge tube to the first component. 
     Statement 3. The system of the statement 1 or 2, wherein the second component is disposed at an end of the gun body. 
     Statement 4. The system of any one of the preceding statements, wherein the first component and the second component each comprise a surface operable to interlock. 
     Statement 5. The system of any one of the preceding statements, wherein the first and second components each comprise a spline. 
     Statement 6. The system of any one of the preceding statements, wherein the electrical contact comprises a section operable to receive a fastener. 
     Statement 7. The system of any one of the preceding statements, further comprising the fastener operable to secure the first component with the second component. 
     Statement 8. The system of any one of the preceding statements, wherein the first component comprises a first mating surface. 
     Statement 9. The system of any one of the preceding statements, wherein the second component comprises a second mating surface. 
     Statement 10. The system of any one of the preceding statements, wherein each mating surface comprises interlocking features. 
     Statement 11. A perforating gun system comprises a gun body; a charge tube movably disposed within the gun body; an alignment assembly comprising: a first component coupled to the charge tube, the first component operable to rotate in concert with the charge tube, wherein an axis of rotation of the first component extends in a direction of the longitudinal axis of the first component; a second component nested within the first component or disposed within a gun body; and an electrical contact extending through the first and second components, wherein the first component is further operable to move in axial directions within the gun body and along the electrical contact to interlock with the second component or separate from the second component. 
     Statement 12. The system of statement 11, wherein the electrical contact is spring-loaded. 
     Statement 13. The system of statement 11 or 12, wherein the electrical contact is not spring-loaded. 
     Statement 14. The system of any one of the statements 11-13, wherein the first component is coaxially aligned with the second component. 
     Statement 15. The system of any one of the statements 11-14, wherein the first and second components comprise splines. 
     Statement 16. A method for orienting at least one shaped charge, the method comprising: securing first and second components together with a fastener that is disposed on an electrical contact, wherein the electrical contact passes through the first and second components; attaching the first component to a charge tube; loading the charge tube with the at least one shaped charge; securing the charge tube within the gun body; moving the charge tube in an axial direction to separate the first component from the second component; rotating the charge tube to orient the at least one shaped charge; and moving the charge tube in an opposite direction such that the first component interlocks with the second component within a gun body. 
     Statement 17. The method of the statement 16, further comprising mating a portion of the first component to a portion of the second component. 
     Statement 18. The method of the statement 16 or 17, further comprising attaching another perforating gun or other connector to prevent the charge tube from being adjusted. 
     Statement 19. The method of any one of the statements 16-18, further comprising compressing a spring upon moving the charge tube in a first direction away from the second component. 
     Statement 20. The method of any one of the statements 16-19, further comprising ratcheting the first component to orient the at least one shaped charge. 
     For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range are specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values even if not explicitly recited. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited. Therefore, the present examples are well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular examples disclosed above are illustrative only, as the present examples may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Although individual examples are discussed, all combinations of each example are contemplated and covered by the disclosure. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. It is therefore evident that the particular illustrative examples disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present disclosure.