Patent Publication Number: US-8113292-B2

Title: Strokable liner hanger and method

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application is a continuation-in-part of United States Non Provisional application Ser. No. 12/175,747, filed on Jul. 18, 2008 now abandoned, the entire contents of which are specifically incorporated herein by reference. 
    
    
     BACKGROUND 
     Liner hangers are common in the hydrocarbon recovery industry and come in a number of sizes, shapes, and operational configurations. Each of these works well for its intended purpose but each also has drawbacks. Sometimes the drawbacks can become problematic and this is especially so when the hangers are used in applications for which they were not originally designed or when the environment of use changes due to changing landscape surrounding the industry as a hole. Often, liner hangers utilize a packer to act as a seal for the liner top. In some embodiments more than one packer is used for a single liner hanger arrangement. 
     SUMMARY 
     A strokable liner hanger including a liner hanger; one of a slide seal and a casing seal sub disposed adjacent the liner hanger; the other of the slide seal and the casing seal sub disposed adjacent the one of the slide seal and the casing seal sub. 
     A method for completing a wellbore with a strokable liner hanger arrangement including running a liner hanger having one of a slide seal and a casing seal sub disposed adjacent the liner hanger, the other of the slide seal and the casing seal sub disposed adjacent the one of the slide seal and the casing seal sub to a target depth in a casing engaging the liner hanger with the casing. 
    
    
     
       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 representation of a strokable liner hanger system as disclosed herein; 
         FIG. 2  is a schematic view of one embodiment of an arrangement as disclosed herein; 
         FIG. 3  is a schematic view of another embodiment of an arrangement as disclosed herein; 
         FIG. 4  is a schematic view of another embodiment of an arrangement as disclosed herein; 
         FIG. 5  is a schematic view of another embodiment of an arrangement as disclosed herein; 
         FIG. 6  is a schematic view of another embodiment of an arrangement as disclosed herein; 
         FIG. 7  is a schematic view of another embodiment of an arrangement as disclosed herein; 
         FIG. 8  is a schematic view of another embodiment of an arrangement as disclosed herein; and 
         FIG. 9  is a schematic view of another embodiment of an arrangement as disclosed herein 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , a portion of a wellbore  10  is illustrated comprising a production casing  12  and an open hole  14  extending therefrom. A liner  16  is represented schematically including one or more inflow control devices/screens  18  and one or more control and or monitoring lines  20 . 
     A liner hanger arrangement is required to locate the liner properly. The inventor hereof has discovered that although liner hangers of the prior art are billed as seals, they do not function as such particularly in wells that have very high temperature gradients. This is particularly true in Steam Assisted Gravity Drainage (SAGD) wells due to the extremely high temperatures the steam brings to the liner  16 . With the heat comes a substantial amount of thermal expansion of the liner. Because the liner is significantly more exposed to the heat than the production casing, the thermal expansion of the liner is correspondingly greater. This causes movement at the liner production casing juncture that movement being experienced directly between the production casing  12  and a liner hanger  24 . Movement is necessary between these components of the well because the thermal expansions of the liner  16  and the production casing  12  are different but the same movement causes problems with respect to sealing of the liner hanger  24  to the casing  12 . 
     To address the foregoing, a strokable liner hanger arrangement  26  is disclosed that allows for the movement of relative thermal expansion while maintaining a reliable seal between the production casing  12  and the liner hanger  24 . Several alternate embodiments as illustrated in  FIGS. 2-8  and described hereunder allow for longitudinal movement of the liner hanger  24  while maintaining a sealed condition with, ultimately, the casing  12 . The precise dimensions of the polished bore, whether on the liner hanger  24  or the casing  12 , is selected for the specific application taking into account the anticipated thermal expansion likely to be experienced. 
     Referring to  FIGS. 2 and 3  two related but reversed configurations are illustrated. In  FIG. 2 , the production casing  12  (note  FIG. 1 ) includes a collar  30 . The collar  30  has at least a thread  32  to connect to the casing  12  and may include a thread  34  to connect to more downhole disposed structure (not shown). In this embodiment the collar  30  provides a polished bore  36  against which one or more seals  38  at an outside surface  40  of the liner hanger  24 . In the reverse configuration of  FIG. 3 , a collar  42  having at least thread  44  and optionally thread  46  provides a seal  48  that may be configured as a seal stack as shown or may be other conventional seal configurations. In the particularly illustrated embodiment of  FIG. 3 , wiper rings  50  are also illustrated but it is to be understood that the use of the rings  50  is optional. 
     In both of the embodiments illustrated in  FIGS. 2 and 3 , the arrangement  26  will include a no go feature  52  at an uphole end of the liner hanger  24  that may be fixed and further will include a downhole no go feature  54  that is retractable and extendible. In these embodiments the downhole no go features  54  must be retractable in order to be able to pass through the polished bore ( FIG. 2 ) or the seal stack ( FIG. 3 ). In order for the no go  54  to have effect however, it must also be extendible. In each of  FIGS. 2 and 3 , the no go feature is illustrated as one or more dogs  56 . For clarity the dogs in  FIG. 2  are illustrated extended and in  FIG. 3  are illustrated retracted. An exemplary system capable of retracting and extending one or more dogs is commercially available from Baker Oil Tools Houston Tex. under product family number 836-02. 
     Referring to  FIGS. 4 and 5 , a very similar configuration is illustrated in a very schematic way to simplify understanding of the distinction. In these figures, rather than a collar, the polished bore  60  or the seal  62  are inserts in the casing string  12 . In other respects these embodiments are similar to those of  FIGS. 2 and 3 . In the embodiments of  FIG. 4 and 5  a separate sub is avoided. 
     Referring now to  FIG. 6 , another embodiment of a strokable liner hanger arrangement is illustrated having a casing mounted no go land  70  that functions in use to provide a positive land for both the uphole no go feature  52  and the downhole no go feature  54 . It is to be recognized also that the uphole and downhole no gos are both located uphole of the seal or polished bore. A consideration for utilizing this configuration is the length of tubing between the no go  52  and the no go  54  to ensure that the stroke of the arrangement  26  is not in excess of the capability of the seal or polished bore to provide a seal against the arrangement  26 . 
     Referring to  FIG. 7 , another alternate embodiment is illustrated that eschews the uphole no go  52  in favor of a single no go  54  that is receivable in a recess  72  in the casing  12 . When the one or more dogs  56  are extended into the recess  72 , both uphole and downhole movement of the arrangement  26  are limited. Similar to the  FIG. 6  embodiment, the length of the recess  72  should be considered relative to the designed in stroke of the seal or polished bore to ensure that the seal to the arrangement  26  remains intact during use of the arrangement. This embodiment has the added advantage that the entire arrangement  26  could be run deeper in the well if for some reason that became desirable. This is because there is no fixed uphole no go  52  that would get hung if such running was attempted with the embodiments of  FIGS. 2-6 . 
     Referring to  FIG. 8 , an embodiment similar to  FIG. 6  is illustrated. In fact the only difference between the embodiment of  FIG. 8  and that of  FIG. 6  is the addition of another retractable and extendible no go  76 . This no go may be configured, in one embodiment, as is no go  54  identified above. As in the benefit of  FIG. 7 , the embodiment of  FIG. 8  can also be run deeper than the intended depth of the arrangement as there is no fixed no go to hang up. 
     Referring to  FIG. 9 , yet another embodiment of the arrangement broadly disclosed herein is illustrated. In this embodiment, a single trip system, even in a preexisting well completion, is enabled. A casing  80  is illustrated which may be a new casing or a preexisting casing or in fact may signify a wall of an open hole as it is possible to install this system in an open hole as well as a cased hole. A liner  82  is illustrated having a strokable liner hanger  84  engaged therewith. The liner hanger  84  includes no gos  86  at an uphole end  88  of liner hanger  84  and no gos  90  at a downhole end  92  of liner hanger  84 . These no gos may be configured as nonmovable types, deployable only types, retractable only types or extendible and retractable types as conditions dictate. The distinctions among these and needs for specific ones of these should be appreciated from the foregoing disclosure of other embodiments of the invention but for efficiency in reading this application it is noted that fixed no gos at the uphole end of liner hanger  84  do not allow motion farther downhole but allow retrieval of the hanger without the other components of this embodiment; retractable no gos at the uphole end allow additional downhole motion; retractable no gos at the downhole end allow retrieval of the hanger without the other components of this embodiment and retractable no gos on both ends allow the retrieval or farther downhole motion discussed. It will be understood that the spacing of the no gos dictates the actual stroke capability of the strokable liner hanger  84 . Extendable no gos avoid gage problems in other locations of the well. 
     Outwardly adjacent the liner hanger  84  are, in radially increasing sequential order, a slide seal  94 , casing seal sub  96 , a fixed seal  98  and slips  100 . These are all mounted to the liner hanger  84  in a selectively releasable manner such as by one or more shear screws, etc. The casing seal sub is settable against the casing  80  or open hole by set down weight as in a mechanically set packer as will be well understood by one of skill in the art or may be settable by hydraulic pressure in known ways. The slips  100  bite into the casing  80  or open hole and the fixed seal  98  forms a pressure tight connection with the casing  80  or open hole. This secures the noted components in place at the casing  80 . The liner hanger  84  may then move relative to the casing seal sub 
     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.