Abstract:
A method for securing a signal propagating line to a downhole component includes configuring the downhole component in a final form prior to securing the line thereto; positioning the line at an outside dimension of the component; and fusing the line to the component with a heat based fusion method and apparatus therefore.

Description:
BACKGROUND 
     Signal propagation lines of many types are utilized in the hydrocarbon recovery industry with great regularity. Such lines, although necessary in contemporary hydrocarbon recovery, are extremely helpful for the same must still be accommodated at a downhole tool string in order to be useful. While there are currently a plethora of attachment means utilized in the downhole industry, additional methods are always welcome. This is particularly so in view of the sensitivity of optic fiber signal propagation lines, which are becoming increasingly ubiquitously sought after. Optic fibers are often used as sensory devices by registering strain therein. In view of this mode of operation, however, residual strain from processing of various strain components for from attachment of the optic fiber to strain components can be detrimental to the accuracy and monitoring system utilizing such fiber. Since greater accuracy of monitoring in the wellbore leads to greater productivity in recovery of hydrocarbons from the wellbore, the art is always well receptive of additional methods and configurations to achieve this end. 
     SUMMARY 
     A method for securing a signal propagating line to a downhole component includes configuring the downhole component in a final form prior to securing the line thereto; positioning the line at an outside dimension of the component; and fusing the line to the component with a heat based fusion method. 
     A low residual stress signal propagation line connection system includes a downhole component preformed into a final form; and at least one heat based fusion securing the line to an outside dimension of the component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring now to the drawings wherein like elements are numbered alike in the several Figures: 
         FIG. 1  is a schematic view of a signal propagation line secured at a downhole component; 
         FIG. 1A  is an enlarged portion of  FIG. 1  that has been circumscribed with line  1 A- 1 A; 
         FIG. 2  is a schematic view of another signal propagation line alternately secured at a downhole component; 
         FIG. 2A  is an enlarged portion of  FIG. 2  that has been circumscribed with line  2 A- 2 A; 
         FIG. 3  is a schematic view of another signal propagation line alternately secured at a downhole component; and 
         FIG. 3A  is an enlarged portion of  FIG. 3  that has been circumscribed with line  3 A- 3 A. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to all of the figures simultaneously, initially, three alternative concepts are disclosed for securing a signal propagation line to a downhole component while avoiding the introduction of excessive residual stress in the materials surrounding the line or in the line itself. Such stresses introduce anomalous readings from the line when using the same as a sensor. In some cases, the anomalies are significant and thus difficult to miss by a seasoned well operator, but in other cases they may be more subtle thereby rendering them difficult to directly detect. In such situations, a well operator might not even know that there is any anomaly to account for and make decisions that do not ultimately result in a positive change in the productivity of the well. Worse yet, due to the residual stresses, the operator may fail to appreciate a condition in the downhole environment that if left unaddressed, will cause the well to require a workover. Because in such situation where the operator is not aware of a problem, he is unlikely to take prophylactic measures to prevent the necessity of a workover. This lack of preemptive action normally will result in a more costly reactive action. 
     In order to address the problems discussed above, the present inventors have devised the below described configurations and methods for securing signal propagation lines, and especially optic fiber lines, to downhole components. 
     Referring to  FIG. 1 , a signal propagation line  10  is illustrated in place on an outside dimension of a cover  12 . It will be appreciated by one of skill in the art that the particular illustration places the cover  12  radially outwardly of a sand screen including a shroud. These components are illustrated only for environment and do not make up a part of the invention. Therefore, they need not be specifically discussed. 
     Referring to  FIG. 1A , an enlarged view of the line  10  at the cover  12  is shown to enable the reader to appreciate the securement of the line  10  to the cover  12 . Initially, it is to be noted that the cover  12  in this embodiment includes a depression  14  therein at the outside dimension  16  of the cover  12 . The depression  14  is of a size and shape to receive at least part of the line  10  therein. As illustrated, the line is not fully received in the depression  14  but this is also contemplated. The line  10  is secured in the depression by a heat based fusion process such as laser welding at least one longitudinal side of the line  10 . As illustrated there are two fusion joints  18 . In addition to the foregoing, it is to be understood that in the configuration as illustrated, the line  10  is secured to the cover  12  only after the cover  12  has been itself constructed. One of skill in the art will be familiar with a common method for constructing tubular covers by helically wrapping a strip of material. In such a method of construction, the line  10  is to be secured after the helical winding is completed. Due to the securement only after the helical winding, induced and residual stress is reduced in the line  10 . As alluded to above, reduction in stresses in the line  10  related to the securement and or the construction of the cover  12 , significantly improve the performance of the line  10  in subsequent operations. 
     In an alternate embodiment and referring to  FIGS. 2 and 2A , the line  10  is secured to the cover  12  without the use of a depression  14  but rather simply directly at the outside dimension  16  of the cover  12 . Without the benefit of the depression  14 , a metal sheet  20  is disposed between the line  10  and the outside dimension  16  of the cover  12 . At least one and as illustrated two heat based fusions is/are created at each longitudinal side of the line  10 . In one embodiment the fusion is created by a laser weld. Each weld is positioned as illustrated and extends from the cover  12  to the line  10  and incorporates the metal sheet  20  in the joint(s)  18 . 
     In yet another alternate embodiment, and referring to  FIGS. 3 and 3A , the line  10  is again placed at the outside dimension of the cover  12  without benefit of a depression  14 . In this embodiment, similar to the embodiment of  FIG. 2 , a metal sheet  20  is employed. By comparing  FIGS. 2A and 3A , one will appreciate a distinct difference in the heat based fusion joints employed. In the  FIG. 3  embodiment, joints  18  are placed on each longitudinal side (at least one side also being contemplated) of the line  10  as in the foregoing embodiments but those joints  18  do not extend to the cover  12  itself. Rather, they extend only to the metal sheet  20 . The metal sheet  20  is then heat based fused to the cover  12 . Because the fusion joints  22  between the sheet  20  and the cover  12  are spaced from the line  10  and the joints  18 , stress from the individual joints is reduced as it is spread over a larger surface area. 
     In each of the embodiments discussed above, the line  10  is positioned at a potentially damage prone location. In order to protect the line from inadvertent damage while, for example, running in the hole, the configurations discussed may sometimes be built with an additional outer cover  24  (as illustrated in each of the figures). The outer cover  24  is a perforate tubular mounted in such a way as to maintain a clearance  26  between an inside dimension  28  thereof and a radially outermost surface  30  of the line  10 . The clearance may be any practical clearance to give a buffer between the cover and the line. The outer cover  24  may be mounted as illustrated with support structures  32  fixed to a base pipe  34  by fasteners or fusion means. 
     While preferred embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.