Mitigation of cable damage during perforation

Abstract

A system and method to minimize the likelihood of cable damage due to downhole operations such as perforating is disclosed. The system includes at least one transducer and at least one orientation device positioned adjacent a cable. A wireless signal from the transducer and/or orientation device is transmitted towards the cable. The wireless signal influences a wired signal transmitted in the cable. The influenced wired signal is used to identify the axial and radial orientation of the cable. The transducer may be secured to a mid-joint collar on the casing string in a portion of the wellbore to be perforated. The transducers are identified and located by the control system and a perforating tool can be adjusted to point away from the cable before firing of the perforating tool.

1 . A cable support mechanism for coupling a cable to a casing section of a downhole casing string, the cable support mechanism comprising:
 a first collar section;   a second collar section coupled to the first collar section; and   a transducer coupled to one of the first collar section or second collar sections.   
     
     
         2 . The cable support mechanism of  claim 1 , further comprising at least one orientation device disposed adjacent the transducer. 
     
     
         3 . The cable support mechanism of  claim 2 , further comprising
 a fiber optic cable disposed adjacent the transducer; and   a control system in optical communication with the fiber optic cable.   
     
     
         4 . The system of  claim 1 , wherein the transducer is selected from the group consisting of an acoustic transducer and a mechanical transducer. 
     
     
         5 . The system of  claim 1 , further comprising a first orientation device and a second orientation device, each orientation device adjacent the transducer and each orientation device oriented to measure in a direction orthogonal to one another. 
     
     
         6 . The cable support mechanism of  claim 5 , further comprising a sensor electrically coupled to the transducer. 
     
     
         7 . The cable support mechanism of  claim 6 , further comprising a cable guide adjacent the transducer. 
     
     
         8 . The cable support mechanism of  claim 7 , further comprising a locking device securing the transducer and the orientation devices to the cable support mechanism in a fixed position and orientation relative to each other. 
     
     
         9 . A system for perforating a casing string in a wellbore in a direction away from a cable deployed along the casing string, the system comprising:
 an elongated casing string;   a first cable deployed along the casing string;   a plurality of spaced apart transducers deployed along the casing string, each transducer coupled to the casing string adjacent the first cable;   a plurality of orientation devices disposed proximate the plurality of transducers; and   a control system in communication with the first cable.   
     
     
         10 . The system of  claim 9 , further comprising a clamping device that couples the first cable to the casing string. 
     
     
         11 . The system of  claim 10 , further comprising a second cable adjacent the first cable, wherein the first cable is a fiber optic cable and the control system is in optical communication with the fiber optic cable. 
     
     
         12 . The system of  claim 11 , further comprising a plurality of clamping devices, wherein each clamping device comprises a first collar section and a second collar section secured to one another so as to extend completely around the casing string, each clamping device carrying one of the transducers and a set of the orientation devices, wherein the set comprises a first orientation device and a second orientation device orthogonally oriented with respect to one another. 
     
     
         13 . The system of  claim 12 , wherein the clamping device further comprises a connecting portion, the connecting portion forming a guide along which the first and second cables run, wherein the transducer and set of orientation devices for the clamping device are carried on the connecting portion adjacent the cable. 
     
     
         14 . The system of  claim 9 , wherein the first cable is an electrical cable, the system further comprising a plurality of sensing devices, each sensing device configured to detect a wireless signal emitted by a transducer and each orientation device adjacent the transducer. 
     
     
         15 . A method for detecting the orientation of a cable in a wellbore, the method comprising:
 deploying a plurality of transducers in a wellbore, the transducers axially spaced apart from one another adjacent a cable extending along a length of the wellbore;   transmitting a first signal from at least one transducer towards the cable;   propagating a second signal down the cable;   altering the second signal based on the first signal; and   utilizing the altered signal to determine the orientation of the cable in the wellbore at the casing section.   
     
     
         16 . The method of  claim 15 , wherein deploying comprises positioning each transducer adjacent a first cable; identifying the position of the first cable in the wellbore at a given point based on the location of the transducer; and discharging a perforating tool based on the identified position of the first cable. 
     
     
         17 . The method of  claim 15 , wherein the first signal is an acoustic signal and the second signal is an optic signal. 
     
     
         18 . The method of  claim 15 , further comprising, modulating the first signal to include location data. 
     
     
         19 . The method of  claim 15 , wherein altering comprises changing the backscattered optic signal. 
     
     
         20 . The method of  claim 16 , further comprising utilizing the discharging from the perforating tool as a seismic source; propagating a seismic signal into the formation; and detecting a reflected seismic signal with the at least one transducer. 
     
     
         21 . The method of  claim 15 , further comprising propagating a seismic signal in a formation and utilizing the transducer to detect the seismic signal.