Distributed sensing system employing a film adhesive

Abstract

A distributed sensing apparatus and system including one or more optical fibers disposed in a channel on the surface of a central member. A layer of film adhesive is disposed between the central member and a sheath. The film adhesive is circumferentially wrapped around the central member prior to arranging the sheath around the central member. The film adhesive is then cured and expanded to firmly attach the optical fiber to the sheath.

1 . A sensing apparatus, comprising:
 a sheath;   a central member disposed in the sheath;   at least one optical fiber disposed with the central member; and   a film adhesive disposed between the sheath and the central member.   
     
     
         2 . The apparatus of  claim 1 , the central member having at least one channel formed thereon, the at least one optical fiber disposed in the at least one channel. 
     
     
         3 . The apparatus of  claim 2 , comprising a plurality of channels in the central member and a plurality of optical fibers, each of the plurality of optical fibers being arranged in one or more of the plurality of channels. 
     
     
         4 . The apparatus of  claim 2 , the at least one channel and the at least one optical fiber being arranged in a helical shape. 
     
     
         5 . The apparatus of  claim 1 , wherein the film adhesive is circumferentially wrapped around the central member. 
     
     
         6 . The apparatus of  claim 1 , wherein the film adhesive substantially fills a void between the at least one optical fiber and the sheath. 
     
     
         7 . The apparatus of  claim 6 , wherein the film adhesive expands to fill the void when cured. 
     
     
         8 . The apparatus of  claim 7 , wherein the expanded film adhesive results in a compressive force on the optical fiber and the central member. 
     
     
         9 . A distributed sensing system, comprising:
 a central member disposed in a sheath;   at least one optical fiber disposed with the central member; and   an adhesive film disposed between the central member and the sheath, the adhesive film being circumferentially wrapped around the central member.   
     
     
         10 . The system of  claim 9  deployed in a well. 
     
     
         11 . The system of  claim 10 , wherein the sheath is coupled to a production tubing or casing. 
     
     
         12 . The system of  claim 9 , wherein the at least one optical fiber is disposed in a channel on the periphery of the central member. 
     
     
         13 . The system of  claim 9 , wherein the at least one optical fiber is disposed in a hole through the central member. 
     
     
         14 . A method for preparing distributed sensing system, comprising:
 disposing at least one optical fiber in or on a central member;   applying a film adhesive onto the central member;   arranging a sheath over the film adhesive and central member; and   drawing down the sheath.   
     
     
         15 . The method of  claim 14  wherein the at least one optical fiber is disposed in a channel on the periphery of the central member. 
     
     
         16 . The method of  claim 14  wherein applying the film adhesive onto the central member is performed by circumferentially wrapping the film adhesive around the central member or by applying the film adhesive longitudinally along the central member. 
     
     
         17 . The method of  claim 14  wherein the sheath is drawn down to a selected internal diameter. 
     
     
         18 . The method of  claim 16 , wherein a radius of the applied adhesive film is less than the selected internal diameter. 
     
     
         19 . The method of  claim 14 , further comprising curing the adhesive film. 
     
     
         20 . The method of  claim 18 , wherein curing the adhesive film causes the adhesive film to expand and substantially fill a plurality of voids between the central member and the sheath.