Patent Publication Number: US-11384625-B2

Title: Device and method for angularly orientating wellbore perforating guns

Description:
BACKGROUND 
     Technical Field 
     Embodiments of the subject matter disclosed herein generally relate to downhole tools related to well perforating, and more specifically, to a gun string that includes at least one element having steering means for controlling an angular orientation of a shaped charge of the gun string. 
     Discussion of the Background 
     In the oil and gas field, once a well  100  is drilled to a desired depth H relative to the surface  110 , as illustrated in  FIG. 1 , and the casing  102  protecting the wellbore  104  has been installed and cemented in place, it is time to connect the wellbore  104  to the subterranean formation  106  to extract the oil and/or gas. This process of connecting the wellbore to the subterranean formation may include a step of plugging the well with a plug  112 , a step of perforating the casing  102  with a perforating gun string  114  such that various channels  116  are formed to connect the subterranean formations to the inside of the casing  102 , a step of removing the perforating gun string, and a step of fracturing the various channels  116 . 
     Some of these steps require to lower into the well  100  a wireline  118  or equivalent tool, which is electrically and mechanically connected to the perforating gun string  114 , and to activate the gun string and/or a setting tool  120  attached to the perforating gun string. The setting tool  120  is configured to hold the plug  112  prior to plugging the well and then to set the plug.  FIG. 1  shows the setting tool  120  disconnected from the plug  112 , indicating that the plug has been set inside the casing and the setting tool  120  has been disconnected from the plug  112 . 
       FIG. 1  shows the wireline  118 , which includes at least one electrical connector, being connected to a control interface  122 , located on the ground  110 , above the well  100 . An operator of the control interface may send electrical signals to the perforating gun string and/or setting tool for (1) setting the plug  112  and (2) disconnecting the setting tool from the plug. A fluid  124 , (e.g., water, water and sand, fracturing fluid, etc.) may be pumped by a pumping system  126 , down the well, for moving the perforating gun string to a desired location, e.g., where the casing needs to be fractured. 
     The above operations may be repeated multiple times for perforating and/or fracturing the casing at multiple locations, corresponding to different stages of the well. These completion operations may require running back and forth the gun string so that each gun is positioned at a desired location. More specifically, after a first gun is fired at its desired position, the remaining guns have to be moved to another position, where a second is going to be fired. Then, the gun string is further moved until the third gun is in position, and so on. However, only positioning each gun to the desired location underground is not enough for an efficient perforation. It is known in the art that certain zones around the casing should not be perforated while other zones need to be perforated. More specifically,  FIG. 2  shows a cross-section through a system  200  that includes plural guns  220  (only one is shown) located in a casing  210 . Around the casing  210 , there are plural zones Z 1  to Z 5  of the subsurface.  FIG. 2  assumes that the gun  220  is positioned at a certain depth inside the casing and shows only one shaped charge  222 , that is directed along a direction D (firing direction herein). Assume that the intent of the operator of the system  200  is to perforate the casing to communicate with zone Z 1 , but not with the other zone. Then, the perforation direction D of the shaped charge  222  is pointing to the wrong zone. 
     This is a real problem faced by the operator of the well. The existing methods for aligning the firing direction of the guns with the desired zones to be perforated include adding a weight W to the gun carrier or an adjacent sub, as illustrated in  FIG. 2 , so that the weight would settle at the bottom of the casing (when the gun is located inside a horizontal portion of the casing) and the shaped charges would have their perforation directions angularly oriented as desired. In other words, the shaped charges are oriented relative to the weight, when the gun is manufactured, so that the shaped charges will perforate along the desired direction when the weight is at the lowest position inside the casing. 
     However, these methods are not very reliable and also do not allow to change an orientation of the gun after the gun has been deployed in the well. Thus, there is a need for a gun string that can adjust its perforation direction as desired for perforating the casing only towards the desired zones and not other zones. 
     SUMMARY 
     According to an embodiment, there is a steerable sub (or any other well device) for controlling an angular orientation of a well tool in a well. The steerable sub includes a housing, a steering element attached to the housing and configured (i) to partially extend out of the housing and (ii) to change an orientation relative to the housing, and an actuation mechanism connected to the steering element and configured to change the orientation of the steering element relative to the housing. 
     According to another embodiment, there is a gun string for perforating a casing in a well. The gun string includes a gun that includes one or more shaped charges, the one or more shaped charges having a firing direction D; and a steerable sub connected to the gun. The steerable sub is configured to rotate relative to a longitudinal axis Y of the casing to align the firing direction D with a desired firing orientation DD. In one application, the sub is a traditional sub and the steerable mechanism is placed on the gun carrier or any other device in the well that moves with the gun string. 
     According to still another embodiment, there is a method for perforating a casing in a well with a gun string. The method includes a step of lowering the gun string into the well, wherein the gun string includes a first gun, and the first gun includes one or more shaped charges, the one or more shaped charges having a first firing direction D 1 , a step of steering the gun string with a steerable sub, while lowering, to minimize an angle between the first firing direction D 1  and a preset first firing orientation DD 1 , a step of stopping the gun string (which is optional) when arriving at a first location along the well, and a step of firing the first gun so that the one or more shaped charges fires along the preset first firing direction DD 1 . 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. In the drawings: 
         FIG. 1  illustrates a well and associated equipment for well completion operations; 
         FIG. 2  illustrates the orientation of a shaped charge relative to plural zones existing around the casing; 
         FIG. 3  illustrates a steerable sub; 
         FIGS. 4A and 4B  illustrate various orientations of a shaped charge when inside a well,  FIGS. 4C and 4D  illustrate how the orientations of the shaped charges can be controlled with a steerable sub, and  FIG. 4E  shows a steerable sub having plural wheels; 
         FIG. 5  shows a gun string having a steerable sub attached to plural guns; 
         FIG. 6  shows a gun string having two steerable subs; 
         FIG. 7  illustrates the various components associated with a steering element for steering the steerable sub; 
         FIG. 8  is a flowchart illustrating a method for steering a gun string to achieve a minimum angle between a firing direction of a shaped charge and a predetermined firing orientation; 
         FIG. 9  illustrates a steerable sub attached with a rotatable arm to a drill pipe; 
         FIG. 10  is a flowchart of a method for steering a gun string inside a well with a steerable sub; and 
         FIG. 11  illustrates a structure of a controller that drives the steerable sub. 
     
    
    
     DETAILED DESCRIPTION 
     The following description of the embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims. The following embodiments are discussed, for simplicity, with regard to a steerable sub attached to a gun string. However, the embodiments discussed herein are also applicable to a gun string that has a steerable gun or to a steerable sub attached to any other well tool that needs to be positioned in the well with a given angular orientation. 
     Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments. 
     According to an embodiment, a steerable sub is provided as being part of a gun string. The steerable sub has means (e.g., a wheel and/or a fin) for controlling an angular position of the sub relative to the gravity. The steerable sub may include one or more of these means. In one application, the steerable sub has an engine and a power source that supplies the engine with power so that the steering means can be controlled. The engine may include an electrical motor, or a solenoid, or a linear motor or any other means for controlling an orientation of the steering means. In another application, the steerable sub includes electronics (e.g., processor, memory, etc.) and one or more sensors for detecting the orientation of the gun relative to the gravity and also for controlling the steering means so that a firing direction of the gun (the shaped charges) can be aligned with the desired direction. 
       FIG. 3  shows a steerable sub  300  that has a housing  302 , the housing having an upper end  304  and a lower end  306  configured to be attached to corresponding guns (not shown) or other well elements. The housing  302  houses the typical components of a sub, e.g., detonator  310 , switch  312 , and communication line  314 . However, in addition to these elements, the steerable sub  300  also includes a steerable section  320  that holds a steering element  330 , an actuation mechanism  340 , a power source  350 , and a controller  352 . The power source  350  supplies power to the actuation mechanism  340  and the controller  352 . In one application, the power source  350  includes one or more batteries. The steering mechanism  330  may include, for example, a wheel  332 . The actuation mechanism  340  may include, for example, an engine  342  and a rod  344 , which is attached to the steering element  330 . The engine  342  may be controlled by the controller  352  for actuating the rod  344 , which turns the wheel  332  in one of two opposite directions F. In this way, the controller  352  is capable to control the direction of the wheel  332 , and thus, implicitly the orientation of the housing  302  while moving through the casing. While the communication line  314  is electrically connected to a main controller operated by the operator at the surface, the controller  352  is configured to operate independent of the communication line  314 . In other words, controller  352  may be electrically independent of the switch  312  and line  314 . 
     Regarding the angular orientation of the housing,  FIG. 4A  shows a case in which the wheel  332  is turned in one direction so that a shaped charge  322  starts to rotate its firing direction D 1  away from the gravity G (note that axis G points opposite to the actual direction of the gravity), so that the two lines D 1  and G form a first angle α 1 .  FIG. 4B  shows the case in which the wheel  332  is turned in the opposite direction so that the shaped charge  322  starts to rotate its firing direction D 2  away from the gravity G, but in the opposite direction than the case shown in  FIG. 4A . The two lines D 2  and G now form a second angle α 2 . Depending on how much the wheel  332  is turned and for how long, the deviation angle α, defined as the angle made by the gravity G and the firing direction D, can be controlled to achieve any orientation of the shaped charge  322 . 
     For example,  FIG. 4C  shows that the steering wheel  332  has been turned so that the firing direction D of the shaped charge  322  forms an angle of about 90 degrees with the gravity G while  FIG. 4D  shows that the firing direction D of the shaped charge  332  forms an angle of about 180 degrees with the gravity G.  FIGS. 4C and 4D  also show a second wheel  334  that is disposed opposite to the steering wheel  332 . The second wheel  334  may be or not a steering wheel. The purpose for the second wheel  334  is to offer a counterforce on the casing  302  so that enough friction is exerted between the steering wheel  332  and the casing  302 . More than two wheels  332  may  334  may be used for a given sub. 
     In one embodiment, as illustrated in  FIG. 4E , three wheels  332 ,  334 , and  336  are distributed around the sub  300  and one or more of these wheels are biased against the inner wall of the casing  400  so that steering of the wheel  332  rotates the housing  302  inside the casing. Note that while  FIG. 3  shows the steering wheel  332  partially located inside the housing  302 , it is also possible that the steering wheel is located completely outside the housing, as illustrated in  FIG. 4E . The biasing against the one or more steerable wheels may be achieved with a biasing mechanism  346  (e.g., a spring) or with a pneumatic system  348  (e.g., an internal piston placed in a pressurized chamber). Other means may be used to bias one or more of the wheels  332 ,  334 , and  336  against the casing  400 . 
     While  FIGS. 4A to 4E  show the steering wheel  332  directly attached to the steering sub  300 , one would understand that the same mechanism may be deployed directly on a gun carrier.  FIGS. 4A to 4D  appear to show that the shaped charge  322  is located in the housing  302  of the steering sub  300 . This is not the case as the shaped charge  322  is placed in a corresponding gun  510 , and not in the steerable sub  300 , as illustrated in  FIG. 5 . The shaped charge  322  has been shown in  FIGS. 4A to 4D  only to provide an indication for the firing direction relative to the gravity. 
       FIG. 5  shows a gun string  500  having a single steerable sub  300 , which is attached to plural guns  510 ,  520 ,  530 . As these guns are attached in a fixed manner to each other and also relative to the steerable sub  300 , any rotation of the steerable sub  300  relative to the casing (not shown in  FIG. 5 ) automatically translates into a corresponding rotation of the guns  510 ,  520 ,  530 , etc.  FIG. 5  also shows that the steerable sub  300  is attached to a wellbore tool  550 . The wellbore tool  550  may be, in one embodiment, a wireline, slickline, coiled tubing, or drill pipe. In another embodiment, as illustrated in  FIG. 6 , another steerable sub  600  may be added to the gun string  500 . For this embodiment, the second steerable sub  600  may have its own steerable wheel  632  as part of the steering element  630 , and the steerable wheel is housed by the housing  602 . The second steerable sub  600  may be sandwiched between a first plurality of guns  510 ,  520  and a second plurality of guns  610 ,  620 . The number of guns distributed between the two steerable subs  300  and  600  may vary from one to many. All these guns and subs form the gun string  500 . 
     In one application, it is possible to have plural steerable subs and plural sets of guns attached to each other, in any order. It is also possible to have non-steerable subs  660 , attached between plural guns  620  and  680 . Any combination of steerable subs, non-steerable subs and guns is possible to be selected to form the gun string  500 , as long as there is at least one steerable sub to control the angular orientation of the firing direction of the shaped charges of the plurality of the guns of the gun string  500 . As also discussed above, it is possible that the steerable sub has a single steerable wheel or more than one steerable wheels. If plural steerable wheels are used, they may be distributed along the external circumference of the housing of the steerable sub, as illustrated in  FIG. 4E . In one embodiment, it is possible that the steerable sub has a single steerable wheel and one or more non-steerable wheels (e.g., casters) as illustrated in  FIGS. 4C and 4D  so that the steerable wheel is biased against the casing and the resultant friction force is used to steer the gun string. One or more steerable subs may be used in any given gun string. The steerable gun(s) may be placed anywhere along the length of the gun string  500 . 
     If only a wheel is used for a given steerable sub (as illustrated in  FIGS. 4A and 4B ), the gun string is decentralized, i.e., its longitudinal axis LA 1  is not coincident with a longitudinal axis LA 2  of the casing as illustrated in  FIG. 4A . However, if more wheels are used, as illustrated in  FIG. 4E , the longitudinal axis LA 1  of the gun string is substantially coincident with the longitudinal axis LA 2  of the casing. A steerable wheel may be biased against the casing not only because of the presence of other wheels that press the steerable sub against the casing, but also because of a biasing mechanism (see, for example, elements  346  and  348  in  FIG. 4E ) that pushes away from the housing the steerable wheel. 
     Controlling the angular orientation of the guns is achieved as now discussed.  FIG. 7  shows the steerable sub  300  having, besides the controller  352 , one or more sensors  710 , electrically connected to the controller. Sensor  710  can include, one or more of an accelerometer, inclinometer, and/or magnetometer. Based on readings from the sensor  710 , the controller  352  can calculate an absolute orientation O of the housing  302  relative to the gravity G. This absolute orientation O, which is schematically illustrated in  FIG. 7 , makes a certain angle with the gravity G. The controller  352  may also calculate the orientation of the gravity G, by using, for example, the magnetometer or a gravity sensor. The firing direction D of the shaped charge(s)  322  of a given gun  510  is known relative to housing from when the gun string has been assembled and this information is stored in a memory associated with the controller  352 . 
     Thus, when the gun string is deployed into the well, the controller  352  is configured to determine the orientation of the gravity G, the absolute orientation O of the gun string, and the actual orientation of the firing direction D. Note that in one embodiment, the absolute orientation O of the gun string may coincide with the firing direction D, otherwise, the angle between the absolute orientation O and the firing direction D is known. In another embodiment, the controller  352  may be configured to determine only the relative angle between the gravity G and the orientation O and/or the gravity G and the firing direction D. With this data, the controller  352  calculates in which direction to rotate the steering wheel  332 , and instructs the actuation mechanism  340  to move the rod  344  to steer the wheel  332  to align the firing direction D with a desired firing direction DD, i.e., minimize the angle between D and DD. The desired firing direction DD is inputted to the controller  352  before the gun string is lowered into the well, or just before the first gun is fired, when there is still possible to communicate with the controller  352  from the surface. Note that after the first gun is fired, wired communication with the controller  352  is likely lost. 
     For these reasons, the controller  352  is configured to operate in an autonomous way. This means that the controller has its own power source  350 , calculates the orientation of the firing direction D based on information acquired from its own sensors  710 , and determines the steering amount for the steering wheel based on the known desired firing direction DD. No other input is necessary from the operator of the well for adjusting (steering) the gun string to adjust its angular orientation (radial direction) within the well. Thus, the controller  352  is capable to adjust the steerable wheel  332  in two modes: (1) continuously, as the gun string is lowered into the well, or (2) at selected times, as the controller determines that the gun string is moving and is below than a certain depth into the well. The adjustment of the steering wheel, and implicitly of the firing direction D, is performed by the controller  352  in an autonomous way, according to a sequence recorded in the memory of the controller before the firing. 
     More specifically, a method of firing three different sets of guns is now discussed with regard to  FIG. 8 . The method starts with step  800 , in which the number (3 in this case) of sets of guns and their firing orientations (D 1  to D 3 ) is input to the controller. Note that the firing orientations D 1  to D 3  may be the same or different from each other. The first set should fire the shaped charges along a desired firing direction DD 1 , the second set along a desired firing direction DD 2 , and the third set along a desired firing direction DD 3 . This information is also provided to the controller in step  800  or a subsequent step. Further, suppose that the first set of guns should fire first at a first location, the second set of guns should fire second at a second location, and the third set of guns should fire third at a third location along the well. All this information is also transferred to the controller. 
     The steerable sub is then lowered in step  802  into the well, together with the three sets of guns. Note that more or less sets of guns may be used and the case discussed herein uses three sets of guns for simplicity. As the gun string (the gun string includes all three sets of guns) is moving toward its first location, where the first set of guns needs to be fired, the controller calculates in step  804 , based on measurements received from the sensor  710 , the angle between the gravity (or the first desired firing position DD 1 ) and the firing direction D 1  of the first set of guns. Note that the controller calculates in this step the angle between the gravity (or the ith desired firing position DDi) and the ith firing direction Di of the ith set of guns, where “i” is originally assigned value 1 and then changed incrementally later. If this angle is larger than a given threshold, for example, 1 to 2 degrees (but other numbers may also be used), the controller  352  decides in step  806  that it needs to adjust the firing direction D 1  of the first set of guns and thus, it instructs in step  808  the steering wheel to change its orientation. This process is repeated then until the firing direction D 1  is within the threshold, to the first desired firing position DD 1 . When the two positions are close enough, then the process advances to step  810 , where the steering wheel is maintained parallel to the longitudinal axis of the casing, so that the firing position D 1  does not change. However, during the step  810 , the controller  352  continues to calculate the orientation of the first set of guns and, if it determines that the first firing direction D 1  has deviated from the first desired firing position DD 1 , it can force the process to return to step  806 . 
     In step  812 , when first set of guns has arrived at its desired first position, the operator of the gun string fires the shaped charges of the first set of guns. Note that because the firing directions D 1  to D 3  of the three sets of guns are different, for this firing step only the first firing direction D 1  of the first set of guns is aligned with the first desired firing orientation DD 1 . After the first set of guns has been fired, the controller checks in step  814  if all the sets of guns have been fired. If the result of this step is affirmative, the operator retrieves in step  816  the gun string from the well as all the guns have been fired. However, if the result is negative, the process continues to step  818 , in which the gun string is moved back from the first position. In step  820 , the value of ith set of guns is increased by one to address the firing of the next set of guns, i.e., the second set of guns according to this description. Then the process returns to step  802 , in which the gun string is again lowered and the controller calculates now the angle between the gravity (or the second desired firing position DD 2 ) and the second firing direction D 2  of the second set of guns. The process steers the entire gun string so that the second desired firing position DD 2  is aligned with the second firing direction D 2  and then fires the second set of guns. The process then continues until all the sets of guns are fired. Note that after firing each set of guns, the gun string is moved back and forth to give the controller the opportunity to adjust the firing direction of the next set of guns for their firing. If plural steerable subs are provided on the same gun string, the controller  352  may control all the steering wheels in unison, as discussed above, to achieve the same angular orientation for the entire gun string. With the method discussed above, it is possible to allow multiple guns to shoot in the same zone, an each gun to have a different firing direction, which will greatly increase the effective density of the zone. 
     According to another embodiment, it is possible to attach a steerable sub to a drill pipe or coiled tubing (called “line” herein). These lines are know to be very stiff, which makes harder, if not impossible, for the steering wheel to turn (twist) the drill pipe or coiled tubing. Thus, for any stiff line that holds the gun string, in this embodiment, as illustrated in  FIG. 9 , the steerable sub  300  is attached to a de-centralizer arm  910 , which is attached to the line  920 . The de-centralizer arm  910  allows the gun string  500  to freely rotate relative to the line  920  as a swivel  922  is located inside the line and allows free rotation of the arm relative to its longitudinal axis Y. In addition, the de-centralizer arm  910  has a first hinged connection  912  with the line  920  and a second hinged connection  914  with the gun string  500 , so that the gun string can move almost freely along a radial direction of the casing  400 . In other words, the first and second hinged connections  912  and  914  allow the arm  910  to freely pivot relative to the line  920  and/or gun string  500 . 
     In this embodiment, to ensure good friction between the steerable wheel  332  (or steerable fin) and the casing, at least one biasing wheel (a caster wheel in this case)  334  is placed on the steerable sub  300  to push the steering wheel against the casing.  FIG. 9  shows two steerable wheels and two biasing wheels. However, one of each wheels may suffice for this embodiment. Also, more than two of each of these wheels may be used.  FIG. 9  also shows a biasing mechanism  346  that applies the biasing force on the biasing wheel  334 . The biasing mechanism may be a spring, hydraulic mechanism, or other known force applying mechanisms. For this embodiment, the line  920  does not rotate when the gun string  500  rotates relative to the longitudinal axis of the casing. As in the previous embodiments, the steering wheel(s) is capable to rotate the gun string with any desirable angle, for example, 2nπ+α, where n can be any positive whole number, including zero, and a is any angle smaller than 2π. 
     A method for deploying a gun string and controlling its orientation relative to a desired orientation position is now discussed with regard to  FIG. 10 . The method includes a step  1000  of lowering a gun string  500  into the well. The gun string includes a first gun  510 , and the first gun  510  includes one or more shaped charges  322 , the one or more shaped charges  322  having a first firing direction D 1 . The method also includes a step  1002  of steering the gun string  500  with a steerable sub  300 , while lowering, to minimize an angle between the first firing direction D 1  and a preset first firing orientation DD 1 , a step  1004  of stopping the gun string  600  when arriving at a first location, and a step  1006  of firing the first gun  510  so that the one or more shaped charges fire along the first firing direction D 1 . 
     The method may further include a step of steering the steerable sub  300  while moving the gun string to minimize an angle between a second firing direction D 2  of the second gun and a preset second firing orientation DD 2 , a step of stopping the gun string  500  when arriving at a second location in the well, and a step of firing the second gun so that one or more shaped charges fires along the second firing direction D 2 . In one application, the step of stopping is skipped, so that the gun string is fired as soon as it arrives at its desired location under ground. The method may also include a step of independently calculating with a processor the angle between the first firing direction D 1  and the preset first firing orientation DD 1  based on readings from one or more sensors housed within the steerable sub. In one application, the processor adjusts a steering element of the steerable sub based on the calculated angle. The steerable sub twists a wellbore tool that is directly attached to the steerable sub. 
     The controller  352  can be implemented, for example, as a computing device  1100  as illustrated in  FIG. 11 . Computing device  1100  may include a server  1101 . Such a server  1101  may include a central processor (CPU)  1102  coupled to a random access memory (RAM)  1104  and to a read-only memory (ROM)  1106 . ROM  1106  may also be other types of storage media to store programs, such as programmable ROM (PROM), erasable PROM (EPROM), etc. Processor  1102  may communicate with other internal and external components through input/output (I/O) circuitry  1108  and bussing  1110  to provide control signals and the like. Processor  1102  carries out a variety of functions as are known in the art, as dictated by software and/or firmware instructions. 
     Server  1101  may also include one or more data storage devices, including hard drives  1112 , CD-ROM drives  1114  and other hardware capable of reading and/or storing information, such as DVD, etc. In one embodiment, software for carrying out the above-discussed steps may be stored and distributed on a CD-ROM or DVD  1116 , a USB storage device  1118  or other form of media capable of portably storing information. These storage media may be inserted into, and read by, devices such as CD-ROM drive  1114 , disk drive  1112 , etc. Server  1101  may be coupled to a display  1120 , which may be any type of known display or presentation screen, such as LCD, plasma display, cathode ray tube (CRT), etc. A user input interface  1122  is provided, including one or more user interface mechanisms such as a mouse, keyboard, microphone, touchpad, touch screen, voice-recognition system, etc. 
     The server may be part of a larger network configuration as in a global area network (GAN) such as the Internet  1128 , which allows ultimate connection to various landline and/or mobile computing devices. 
     The disclosed embodiments provide methods and systems for controlling an angular orientation of a gun string while in a well so that one or more shaped charges are fired along a desired direction. It should be understood that this description is not intended to limit the invention. On the contrary, the exemplary embodiments are intended to cover alternatives, modifications and equivalents, which are included in the spirit and scope of the invention as defined by the appended claims. Further, in the detailed description of the exemplary embodiments, numerous specific details are set forth in order to provide a comprehensive understanding of the claimed invention. However, one skilled in the art would understand that various embodiments may be practiced without such specific details. 
     Although the features and elements of the present embodiments are described in the embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the embodiments or in various combinations with or without other features and elements disclosed herein. 
     This written description uses examples of the subject matter disclosed to enable any person skilled in the art to practice the same, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims.