Patent Publication Number: US-2015083439-A1

Title: Method And Systems For Stick Mitigation Of Cable

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     None. 
     FIELD OF THE DISCLOSURE 
     The disclosure generally relates to methods and systems for stick mitigation on cable. 
     BACKGROUND 
     Cable is used in many well services. For example, cable is used to deploy tools into the well. The tension on cable during well service has increased as wells are drilled to greater depths. 
     Capstans are used to reduce tension on cable. The capstan, however, requires cable to bend about sheaves, and bending the cables about the sheaves can reduce the cable&#39;s working ends-fixed break strength (EFBS) to about from 60 percent to about 65 percent of the cable&#39;s rated EFBS. 
     A need exists, therefore, for systems and methods for stick mitigation of cable that allows cable to have a larger working EFBS, allowing greater forces to be applied to the cable if the cable, a tool string connected with the cable, or both get stuck in the well. 
     SUMMARY 
     An embodiment of a system for stick mitigation of cable in a well can include a derrick operatively aligned with the well. The derrick can support a cable, and a cable injector can be connected with the derrick. The cable injector can be operatively aligned with the well and the cable, and the cable injector can be disengaged as the cable is run into the well. In an embodiment, a drum can be used to move the cable relative to the well, and a capstan can be located between the derrick and the drum. 
     An embodiment of a method for stick mitigation of cable in a well can include performing a well service using cable supported by a derrick. The method can further include moving the cable relative to the well with a drum during normal operations. The method can also include engaging a cable injector to pull on the cable if the cable is stuck in the well. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts an example embodiment of a system. 
         FIG. 2  depicts another example embodiment of a system. 
         FIG. 3  depicts an example of cable injector blocks. 
         FIG. 4  depicts an example cable. 
         FIG. 5  depicts an example method. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Certain examples are shown in the above-identified figures and described in detail below. In describing these examples, like or identical reference numbers are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic for clarity and/or conciseness. 
     A system for stick mitigation of cable in a well can include a derrick operatively aligned with the well. The derrick can support the cable as the cable is used to perform well services. The cable can be any cable used in well services; however, in an embodiment the cable is a wireline cable. The wireline cable can be a polymer-locked, crush-free wireline cable or any other wireline cable. 
     A cable injector can be connected with the derrick. The cable injector can be connected with the derrick in any manner. For example, the cable injector can be hung on the derrick and aligned with the well. The cable injector can be operatively aligned with the well and the cable. For example, the cable injector can be aligned with the cable and well allowing the cable injector to provide force to the cable that is perpendicular to the well. The cable injector can be disengaged during normal operations. Normal operations, as used herein, means that neither the cable, a tool string connected with the cable, or both are stuck in the well. 
     During normal operations, a drum connected with the cable can be used to move the cable relative to the well. For example, the drum can run the cable into the well and pull the cable out of the well. In an embodiment of the system, a capstan can be located between the derrick and the drum. 
     An example method for stick mitigation of cable in a well includes performing a well service using a cable supported by a derrick, and moving the cable relative to the well with a drum. During normal operation of the system the well service can be performed with the cable injector disengaged; however, the cable injector can be engaged to pull on the cable if the cable is stuck in the well during the well service, deployment of the cable, retrieval of the cable, or combinations thereof. The cable injector can pull on the cable with a force that is up to about 85 percent of the cables designed ends-fixed break strength. 
     Turning now to the FIGS.  FIG. 1  depicts an example embodiment of a system. 
     The system  100  includes a derrick  110  operatively supporting a cable  120 . For example, a plurality of sheaves can be connected with the derrick  110 , and the sheaves can guide and support the cable  120 . The cable  120  at one end can be connected with a service tool  122 . The service tool  122  can be measurement equipment, telemetry equipment, pumping equipment, perforating equipment, other downhole equipment, or combinations thereof. For example, a combination of sensors and other downhole equipment can be assembled to form a toolstring, and the toolstring can be connected with the cable. The cable  120  at another end can be connected with a drum  140 . 
     The drum  140  can be used to run the cable  120  into the well  160 . The drum  140  can move the cable  120  relative to the well  160 . The cable  120  can be used to deploy the attached service tool  122  to a desired depth so a service operation can be performed. After the service operation is performed, the drum  140  can be used to retrieve the cable  120  and the attached service tool  122 . 
     A cable injector  130  is operatively connected with the derrick  110 . The cable injector  130  can be any cable injector. A power source  170  can be in communication with the cable injector  130 . The power source  170  can be an electric power source, a hydraulic power source, a pneumatic power source, or combinations thereof. 
     During normal operation of the system  100 , the cable injector  130  is disengaged, and the drum  140  provides the force on the cable  120  that is necessary to run the cable  120  into the well  160  and pull the cable  120  out of the well  160 . The cable  120 , the connected service tool  122 , or both may get stuck in the well  160 . For example, the service tool  122  may catch on an obstruction in the well  160 . Additional force may need to be applied to the cable  120  to free the cable  120 , the service tool  122 , or both when the cable  120 , the service tool  122 , or both are stuck, and normal operation of the system is no longer possible. 
     To provide the additional force, the cable injector  130  is engaged and the power source  170  provides power to a drive assembly of the cable injector  130 . Engaging the cable injector  130  can include providing power, using the power source  170  to one or more actuators (not shown), such as linear actuators, to move a pair of cable blocks (shown in detail below) into engagement with one another. The engaged cable injector  130  can provide force to the cable  120 , and the force applied to the cable  120  can be perpendicular to or substantially in line with the well  160 . Accordingly, the cable  120  is pulled in a straight line by the cable injector  130 . The cable injector  130  provides force until the cable  120  and the service tool  122  are free to move relative to the well, allowing normal operations to resume. Once normal operations resume, the cable injector  130  is disengaged. 
       FIG. 2  depicts another example embodiment of a system. The system  200  includes the derrick  110 , the cable injector  130 , the cable  120 , and the drum  140 . The power source  170  can be in communication with the cable injector  130 , and the service tool  122  can be connected with the cable  120 . 
     The system  200  can also include a capstan  150 . The capstan  150  can be located between the derrick  110  and the drum  140 . The capstan  150  can reduce tension on the cable  120  during normal operations. For example, as the drum  140  runs the cable  120  into the well  160  to deploy the service tool  122 , the capstan  150  can reduce the tension on the cable  120  to the drum  140 . 
       FIG. 3  depicts an example of cable injector blocks. A first cable injector block  310  and a second cable injector block  320  can cooperate to provide force to the cable  120 , when the cable injector is engaged. 
     The first cable injector block  310  can include a first belt  314 . The first belt  314  can be located on a first drive assembly (not shown). The first drive assembly can be any drive system. Illustrative drive assemblies include hydraulic systems, electric systems, and pneumatic systems. A first channel  312  can be located on the first belt  314 . The first channel  312  is configured to fit about the cable  120 . 
     The second cable injector block  320  can include a second belt  324 . The second belt  324  can be disposed about a second drive assembly (not shown). The second drive assembly can be any drive system. The second belt  324  can have a second channel  322 . The first channel  312  is aligned with the second channel  322  when the injector block is operatively installed on the derrick. Accordingly, the first belt  314  and the second belt  324  can engage one another when the injector block is engaged, and the first channel  312  and the second channel  322  can secure about the cable  120 . The belts  314  and  324  can move and provide force to the cable  120 . 
     The belts  314  and  324  can be made of any material that allows the belts  314  and  324  to tightly grip the cable  120  without damaging the cable  120 . The material can be softer than the cable  120 . Illustrative materials include wood, polymers, or metal. 
       FIG. 4  depicts an example cable. The example cable  120  includes a core  410 , inner armor  420 , and outer armor  430 . 
     The core  410  can have any number of conductors  412 . The conductors  412  can have a jacket  414  disposed thereabout. A polymer  422  can fill the core  410  and interstitial spaces between the inner armor  420  and the outer armor  430 . The polymer  422  can be crush-resistant polymer. The polymer  422  locks the armor layers  420  and  430  with the jacket  414 . Accordingly, the armor layers  420  and  430  are locked with the core  410 . The design of the cable  120  provides a mechanically rigid, torque-balanced and crush-free wireline cable that reduces issues with core coldflow, cable rotation, plastic stretch, armor stranding, and bird-caging. 
     The cable  120  can be spooled under high-tension. For example the cable  120  can be spooled at a tension of about 13,000 lbf, handle instantaneous pulls of about 18,000 lbf, and with a safety margin of about 9,000 lbf. 
       FIG. 5  depicts an example method. The method  500  is depicted as a plurality of blocks or operations. 
     The method  500  includes performing a well service using a cable supported by a derrick (Block  510 ). The method  500  continues by moving the cable relative to the well with a drum during normal operations (Block  512 ). In an embodiment of the method a capstan located between the derrick and drum is used to reduce cable tension during normal operations. 
     The method also includes engaging a cable injector to pull on the cable if the cable is stuck in the well (Block  514 ). The cable can be stuck in the well when a service tool connected with the cable is stuck or the cable is otherwise stuck. The cable injector can be engaged by providing power to actuators and moving injector blocks into engagement about the cable. Power can then be delivered to a drive system connected with the cable injector, and the cable injector pulls on the cable with a force that is up to about 80 percent of the cables ends-fixed break strength. During normal operations, the cable injector is disengaged. 
     Although example assemblies, methods, systems have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers every method, apparatus, and article of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.