Patent Publication Number: US-2011073313-A1

Title: Device for fixing a valve to a tubular member

Description:
The present invention relates to a device for fixing a valve to a tubular member, in particular valves being adapted to control the flow of fluid out from or into a subterranean reservoir. 
     When valves are to be mounted to tubular members, practice has shown that difficulties are easily occurring. Problems arise in finding a appropriate and simple way for the fixation as such. It is nor obvious that the valves remain in a fixed position during situations in which the tubular member is lowered into a wellbore or a workover tool is running therethrough. 
     Therefore, a main object is to provide for simple and cost-effective mounting of the valves radially through the wall of the tubular member or axially disposed therein. It is also an object to provide for a fixation involving the valves are not susceptible of being unintentionally detached from the tubular member but, if needed, also is able of being removed, e.g. to replace a damaged valve in situ. 
     These objects are achieved by a device for fixing a valve to a tubular member being situated in wellbore formed in a subterranean reservoir and is having at least one drainage section including a plurality of such valves as to allow the flow of fluid into and out from the tubular member, respectively, distinguishing itself in that the valve is secured to the tubular member by means of a sleeve portion, the sleeve portion being part of the valve or is formed like a separate socket into which the valve is to be arranged. Favourable embodiments are specified in the dependent patent claims and are, briefly spoken, involving that the valve can be secured by means of threads and/or at least one weld, be stabilised by using an insert in an area between the valve and tubular member, be mounted in level with or above or below the outer or inner surface of the tubular member, and be mounted in an radial or axial direction to the tubular member. 
    
    
     
       Now, the present invention is to be described more in detail with reference to preferred embodiments illustrated in the drawings, in which: 
         FIGS. 1   a - c  show schemically embodiments of a valve having a sleeve portion used when securing the valve to a tubular member by means of threads; 
         FIGS. 2   a - b  depict schemically another embodiments similar to  FIGS. 1   a - c  but the threads have been replaced by at least one weld; 
         FIGS. 3   a - b  illustrate schematically yet another embodiments including an insert adapted to the curvature of the tubular presenting a flat surface for a valve flange; 
         FIGS. 4   a - c  show schemically still another embodiments using a separate socket securing the valve to the tubular member; 
         FIGS. 5   a - b  depict in perspective the valve being secured in a drainage section of the tubular member; 
         FIGS. 6   a - c  illustrate schemically still another embodiments including an inner lining; and 
         FIGS. 7   a - b  show schemically embodiments in which the sleeve is situated inside the tubular member. 
     
    
    
     At first, some general observations are to been given. As illustrated in  FIG. 5   a , an autonomous or self-adjusting valve or flow control apparatus according to WO-A 1  2008/004875 is used to exemplify one of all sorts of valves  1  applicable for the present invention. Even though  FIG. 5   b  shows a tubular member with a drainage section  21  extending in a horizontal direction, this fact is not involving the exclusion of drainage sections orientated in other directions such as vertical, deviated, etc. Except in  FIGS. 7   a - b,  all of the valves are allowing the fluid to flow into the tubular member. The present invention can also be used with valves being situated in the opposite direction and, thus, allowing the flow of fluid out of the drainage section into an subterranean formation during injection. It is understood that a combination of valves orientated in both directions is within the scope of the present invention involving the tubular member can be used during both production and injection. In the drawings the valve is not depicted in a correct scale but enlarged to clarify the details thereof. The valve can be customised for any needs, e.g. with a height corresponding to the wall of the tubular member. 
     As already mentioned above, the present device is developed for the fixation a valve  1  to a tubular member  2  to control the flow of fluid out from or into a subterranean reservoir, not shown. Thus, the tubular member is to be situated in a wellbore formed in such subterranean reservoirs to produce hydrocarbons, for instance, or inject various injection fluids out from and into the reservoir, respectively. The tubular member is having at least one drainage section  11  including a plurality of such valves as to allow the flow of fluid into or out from the tubular member. According to the present invention each of the valves is secured to the tubular member by means of a sleeve portion  3 , and the sleeve portion is an integrated part of the valve, i.e. a monolithic component thereof, or is formed like a separate socket  4 ;  4 ′ into which the valve is to be arranged. 
     According to a first embodiment the valve has a sleeve portion  3 , see  FIGS. 1   a - c,  being part of the valve and arranged at a valve shaft  36 . The sleeve portion is provided with threads  31 , and a bore through the tubular member is having complementary threads, not depicted. The valve is fastened by screwing the threads into one another. To enhance the connection between the valve and tubular member, a suitable glue or soldering can be used supplementary to the threads  31 , not illustrated. Alternatively, as illustrated in FIG,  1   c,  a weld  32  can arranged in an area between the tubular member and valve. It should be noted that the dotted lines do not specify an inner wall of the valve shaft but only the horizontal extension of the threads  31 . 
     As an alternative embodiment, see  FIGS. 2   a - b,  the sleeve portion  3  is fastened using a weld  33  totally filling the gap between the sleeve portion and tubular member or both a wedge weld  34  and weld deposit  35 . In such a case the valve shaft can be formed without any threads. 
     According to  FIGS. 3   a - b  a further embodiment corresponding to the one above is having an insert  5  arranged in an area between the valve flange  11  and tubular member  2 . The insert levels for the curvature of the tubular member and is providing a flat base for the valve flange  11  which involves a more robust fixation. Both the valve flange and insert are provided with seals  12 ,  52  of appropriate kind, for instance but not exclusively an O-ring, arranged in grooves or the like. The insert can be made from any suitable materials. If an elastomer is used, the seals can be omitted. 
     The sleeve portion  3  must necessarily not be formed in level with the outer surface of the valve shaft  36  but can, if needed, extend outside this surface, not illustrated. Such a configuration is useful in case of an elastomeric insert  5  including a bushing made from metal to prevent over-tightening of the valve  1 , not illustrated. 
     In yet another embodiment, see  FIGS. 4   a - c,  the sleeve portion is formed by a separate socket  4  in which threads  41  are formed in a surface facing the valve shaft  36 . The socket  4  as such is secured to the tubular member  2  by means of a suitable weld, and the threads  41  are formed complementary to the threads in the valve  31  enabling screwing the valve  1  and socket into one another. As mentioned above, the thread connection can be supplemented by a glue or soldering. A suitable seal  43  is arranged in an area between the socket and valve flange  11 , e.g. in a groove or the like. To enable mounting below an outer surface of the tubular member  2 , the socket  4  is provided with a recess  44 , see  FIGS. 4   b - c.  As an alternative to threads the socket can provided with a groove  45  to accommodate the valve flange  11  and a lock ring  45  fastening the valve in a releasable manner within the socket. 
     To prevent a lower portion of the valve  1  from making a sharp egde which is able to destory objects being lowered into the tubular member  2 , for instance, an inner lining  6  is provided to surround this lower portion extending below an inner surface of the tubular member. As depicted in  FIGS. 6   b - c,  the lining can be formed like a separate lining and monolithic part of the tubular member, respectively. Particulary when formed monolithically, the tubular member is provided with a recess  22  enabling the valve to be situated below the outer surface thereof. 
     Normally, the valves  1  are arranged in a radial direction through the tubular member  2  but there can be situations in which the valves are to be axially mounted inside the tubular member, e.g. to control the flow of fluid in a branch pipe and the like. Then, as illustrated by  FIGS. 7   a - b,  the socket is orientated in a longitudinal direction inside the tubular member and secured in any proper manner against the inner surface thereof. In an alternative the socket is formed by a partition  47  having more than one opening therethrough to accommodate the valves. It is understood that variaos features from the embodiments above are applicable also in this instance and are, therefore, not to be repeated.