Patent Abstract:
An expansion assembly is run into the well as the expandable liner is made up. A work string is tagged into the expansion assembly and run to depth. Pressure drives the swage to initially expand and move uphole with the attached work string until the liner is expanded to set at least one external packer. The balance of the expansion in the uphole direction is continued until the string is expanded into sealing support of a higher string in the wellbore and the variable swage comes out of the hole with the work string. A shoe is milled out and the process can be repeated.

Full Description:
FIELD OF THE INVENTION 
       [0001]    The field of the invention relates to techniques for tubular expansion and sealing in open hole with attachment techniques to an existing tubular. 
       BACKGROUND OF THE INVENTION 
       [0002]    Various techniques have been developed to expand liners and attach them to existing casing already in the wellbore. Some of these techniques involve running a liner with a wide bell at the bottom where the expansion equipment is located and then driving the swage up the liner and out the top and along the way setting external seals to the surrounding casing as the swage makes an exit. One such process is shown in U.S. Pat. No. 6,470,966. The extensive list of prior art included in that patent is representative of the state of the art in downhole tubular expansion techniques that include attachment to an existing tubular. Other patents show the use of swages that include a series of retractable rollers that can be radially extended downhole to initiate a tubular expansion such as of a casing patch as for example is illustrated in U.S. Pat. No. 6,668,930. Some devices swage in a top to bottom direction as illustrated in U.S. Pat. No. 6,705,395. 
         [0003]    What is needed and addressed by the present invention are refinements to the previous techniques that improve performance, mitigate risk and save time to reduce the cost to the operator. Techniques involving expansion in stages coupled with cementing in between are envisioned. An adjustable swage to expand on location removes the need for oversized bells to house the expansion equipment as done in some techniques. Techniques using cement or just sealing externally in open hole are envisioned. Composite materials facilitate subsequent drill out while improved shoe configuration improves circulation when tripping into the hole. The shoe and/or liner can be rotationally locked to work the string for delivery downhole. These and other advantages will become more apparent to one skilled in the art from a review of the description of the preferred embodiments and the associated drawings, while recognizing that the full scope of the invention is given by the claims. 
       SUMMARY OF THE INVENTION 
       [0004]    An expansion and cementing assembly is run into the well as the expandable liner is made up. A work string is tagged into the expansion assembly and run to depth. Pressure drives the swage to initially expand and move uphole with the attached work string until the liner is expanded above the location of the subsequent cement placement. The assembly is then lowered to engage the guide/float shoe to perform the cementing step. The swage assembly is then released from the guide/float shoe and the balance of the expansion is performed without further expansion against the recently placed cement. The expansion assembly can start at the guide/float shoe or higher, in which case expansion can occur initially in a downhole direction and later be completed in an uphole direction. Variations without cementing are also contemplated. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a view of a wellbore that has been cased with an open hole segment below; 
           [0006]      FIG. 2  is the view of  FIG. 1  showing a liner with a float shoe inserted into the open hole segment through the casing; 
           [0007]      FIG. 3  is the view of  FIG. 2  with the swage assembly being run in; 
           [0008]      FIG. 4  is the view of  FIG. 3  with the circulation established through the swage assembly and the float shoe as the liner is run in; 
           [0009]      FIG. 5  is the view of  FIG. 4  with the swage assembly expanded but not yet driven; 
           [0010]      FIG. 6  is the view of  FIG. 5  with the swage assembly released from the supporting string and being driven down to the float shoe; 
           [0011]      FIG. 7  is the view of  FIG. 6  with the circulation re-established after the swage assembly engages the float shoe; 
           [0012]      FIG. 8  is the view of  FIG. 7  with the support string releasing the liner and being advanced further into the liner using additional stands added above; 
           [0013]      FIG. 9  is the view of  FIG. 8  with the swage assembly again latched to the supporting string and cement pumped through the float shoe to fill the annulus around the already expanded liner; 
           [0014]      FIG. 10  is the view of  FIG. 9  with the swage assembly now driven up to complete the expansion of the liner top into the casing; 
           [0015]      FIG. 11  is the view of  FIG. 10  with the swage assembly out of the fully expanded liner and the liner hanger to the surrounding casing engaged; 
           [0016]      FIG. 12  is a view similar to  FIG. 1  to illustrate an alternative method; 
           [0017]      FIG. 13  is the view of  FIG. 12  with the liner in the well showing a swage assembly connected to the float shoe; 
           [0018]      FIG. 14  is the view of  FIG. 13  with the work string run in to engage the swage assembly; 
           [0019]      FIG. 15  is the view of  FIG. 14  with the circulation established as the liner is run into the open hole; 
           [0020]      FIG. 16  is the view of  FIG. 15  with the swage assembly extended in the liner; 
           [0021]      FIG. 17  is the view of  FIG. 16  with the swage assembly pressure released from the float shoe and ready to move uphole; 
           [0022]      FIG. 18  is the view of  FIG. 17  with the swage assembly driven uphole; 
           [0023]      FIG. 19  is the view of  FIG. 18  with the swage assembly again engaged to the float show after initial expansion; 
           [0024]      FIG. 20  is the view of  FIG. 19  with the annulus around the expanded portion of the liner being cemented; 
           [0025]      FIG. 21  is the view of  FIG. 20  with the swage assembly driven up to complete the expansion above the cemented zone and engage the hanger on the liner to the casing; 
           [0026]      FIG. 22  is the view of  FIG. 21  with the swage assembly removed from the liner; 
           [0027]      FIG. 23  is another view of  FIG. 1  for an alternative embodiment without cementing the liner; 
           [0028]      FIG. 24  is the view of  FIG. 23  with the liner in the hole and suspended from the surface with an open hole packer outside the liner; 
           [0029]      FIG. 25  is the view of  FIG. 24  with the string latched into the swage assembly that is supported at the float shoe; 
           [0030]      FIG. 26  is the view of  FIG. 25  with the circulation established for running in the liner; 
           [0031]      FIG. 27  is the view of  FIG. 26  with the swage assembly expanded; 
           [0032]      FIG. 28  is the view of  FIG. 27  with the swage assembly released to move uphole from the float shoe; 
           [0033]      FIG. 29  is the view of  FIG. 28  with the liner expanded and the open hole packer set; 
           [0034]      FIG. 30  is the view of  FIG. 29  with the swage expanding the hanger on the liner into contact with the casing; and 
           [0035]      FIG. 31  is the view of  FIG. 30  with the swage assembly out of the liner and the float shoe ready to be drilled out or retrieved to the surface. 
           [0036]      FIG. 32  shows an open hole that can be under reamed with respect to the cased hole above; 
           [0037]      FIG. 33  shows a liner inserted and expanded to hang off the casing above with options to seal it with cement or external packers or both or neither; 
           [0038]      FIG. 34  shows an under reamed open hole below the already expanded and hung off liner; 
           [0039]      FIG. 35  shows a production string through the expanded liner and hung off the casing where the production string can be cemented or not as needed; 
           [0040]      FIG. 36  shows a casing patch application using expansion; 
           [0041]      FIG. 37  shows an open hole patch using expansion; 
           [0042]      FIG. 38  shows an open hole patch in an under reamed hole; 
           [0043]      FIG. 39  shows an under reamed open hole below a cased hole; 
           [0044]      FIG. 40  is the view of  FIG. 39  with a liner inserted and expanded to create a lower bell in the under reamed portion of the well; 
           [0045]      FIG. 41  is the view of  FIG. 40  with the shoe drilled out of the bottom of the expanded liner and further showing a variety of sizes of new hole to be drilled deeper; 
           [0046]      FIG. 42  is the view of  FIG. 41  with a production string run in and hung off the casing and optionally cemented; 
           [0047]      FIG. 43  is the view of  FIG. 41  with a second liner hung off from the bell of the liner above and optionally externally sealed with cement or/and one or more packers pr neither; 
           [0048]      FIG. 44  is the view of  FIG. 43  with the lower liner expanded in two dimensions to create a lower bell; 
           [0049]      FIG. 45  is the view of  FIG. 44  with the length of the liner below the liner lap expanded to allow for high setting a subsequent liner in the event of a hole collapse; 
           [0050]      FIG. 46  shows a sequence of liners allowing the sidetrack exit while maintaining bore size; 
           [0051]      FIG. 47  shows a cased hole with a bell on the lower end of the casing that can be there for run in or created with expansion of a subsequent liner and an under reamed open hole below; 
           [0052]      FIG. 48  is the view of  FIG. 45  with a liner run in and hung off in the casing bell and optionally sealed with cement or/and one or more external packers or neither; 
           [0053]      FIG. 49  shows a casing with a lower bell and an upper liner hung from the bell with an open hole below the size of the expanded liner or under reamed; and 
           [0054]      FIG. 50  is the view of  FIG. 47  with a production liner inserted through the expanded liner above it and the production liner hung from above the bell in the casing; 
           [0055]      FIG. 51  shows a cased hole with a bell on the lower end of the casing that can be there for run in or created with expansion of a subsequent liner and an under reamed open hole below. 
           [0056]      FIG. 52  is the view of  FIG. 51  with a liner run in and hung off in the casing bell with a second casing bell positioned at the bottom that can be created upon expansion of the liner or created with expansion of a subsequent liner and is optionally sealed with cement and/or one or more external packers or neither. 
           [0057]      FIG. 53  is the view of  FIG. 52  with the shoe drilled out and the open hole below under reamed to accommodate a subsequent liner. 
           [0058]      FIG. 54  is the view of  FIG. 53  with an additional liner shown run in and hung off as the one above it and as subsequent liners can also be installed. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0059]      FIG. 1  shows casing  10  in a wellbore  12  that extends from the surface  14 . The open hole portion  16  has a pilot hole  18  at the lower end. A rig  19  is illustrated schematically at the surface  14 . In  FIG. 2  a liner  20  is supported from the rig  19  and extends into the open hole  16 . Liner  20  has a hanger/packer  22  on the outside that will eventually support the liner  20  and seal it to the casing  10 . A sealed latch assembly  24  is located inside the float shoe  26 . Float shoe  26  has a spring loaded one way valve  28  as well as a bottom exit  30  as well as side exits  32 . The side exits promote well conditioning during circulation when running in the liner  20 . The float shoe  26  allows flow in the liner  20  to exit but prevents reverse flow such as cement later pumped through the liner  20  and into the surrounding annulus  34 . The float shoe  26  can also be made of a soft composite material or other similar materials that promote rapid drill out after the cementing is completed. 
         [0060]      FIG. 3  shows the insertion of an assembly  36  that comprises from the bottom up a latch component  38  designed to seal and latch to component  24  when brought into contact with it. Further uphole is a piston assembly  40  designed to selectively change the size of the adjustable swage  42  such as is illustrated in U.S. Pat. No. 7,128,146, for example. Further up is an uphole oriented swab cup  44  and a disconnect  46 . A section of pipe  50  spaces the lower swab cup  44  from an oppositely oriented upper swab cup  48 . Further up is a running tool  52  shown gripping the interior of the liner  20  and finally an annular debris barrier  54  is designed to keep debris from getting into the liner  20  as it is circulated when being run into the well  12 . 
         [0061]      FIG. 4  shows a run in string  56  starting to be assembled above the debris barrier  54  and the liner  20  now supported through the string  56  off of rig  19  as it is delivered deeper into the wellbore with circulation through the assembly  36  represented by arrow  58  and return flow represented by arrow  60 . In this view it is easy to see the function of the debris barrier  54 . The valve  28  responds to delivered pressure from the surface  14  to open and let the flow out through the lateral shoe passages  32  to allow for a secondary flow path in case the bottom is plugged when resting on bottom. 
         [0062]    In  FIG. 5  a plug or dart or some other obstructing device  62  is dropped or pumped until landed to seal off passage  64 . Then with passage  64  closed at its lower end and pressurized the pressure  66  acts on piston assembly  40  as indicated by arrows  66 . The swage assembly  42  grows in radial dimension to create an initial bump out  68  in the liner  20 . 
         [0063]    In  FIG. 6  the pressure in passage  64  has been further increased to cause a separation between components  46  so that the applied pressure in passage  64  now can enter space  70  as indicated by arrows  72 . That pressure acts on lower swab cup  44  that looks uphole while the liner  20  which is gripped by running tool  52  and is supported off of string  56  from rig  19  remains immobile despite uphole pressure on upper swab cup  48  which is downhole oriented. Arrows  66  indicate that pressure on the piston assembly  40  continues to keep the swage assembly  42  at an enlarged dimension as it travels toward the float shoe  26  until components  38  and  24  re-latch and seal as shown in  FIG. 7 . 
         [0064]    In  FIG. 7  components  38  and  24  have latched and a pressure buildup has popped a disc internal to dart  62  so that circulation can be established with the bulk of the liner  20  below the casing  10  already expanded. Arrows  72  and  74  represent circulation flow through passages  32  and  36  in the float shoe  26 . 
         [0065]      FIG. 8  shows that circulation has stopped and the float shoe  28  is resting on bottom in the pilot hole  18 . The string  56  is being added to at the surface  14  to again bring together the connection  46  so that cementing around the already expanded portion of the liner  20  can take place. 
         [0066]    In  FIG. 9  the connection  46  is brought together in a sealing relationship and cement  76  is delivered into annulus  34  to the top  77  of the expanded portion of liner  20 . The cement  76  goes down passage  64  and through the one way valve  28  in the float shoe  26  to the annulus  34 . A wiper plug or dart  78  wipes passage  64  clear of the cement  76 . Optionally some cement  76  can be pumped above plug  78  to ease subsequent drill out as shown in  FIG. 10 . 
         [0067]    In  FIG. 10  with wiper plug  78  remaining landed a buildup of pressure in passage  64  builds an uphole pressure on sealed latch  24  which has a downhole oriented swab cup  80  whose presence results in an uphole force represented by arrow  82  to drive the assembly  36  uphole to finish the expansion of the liner  20  into a sealed relationship with the casing  10 . The swage assembly  42  remains at maximum dimension because the piston assembly  40  is pressurized at this time as the movement uphole of the  36  continues. 
         [0068]      FIG. 11  shows the expansion of the liner  20  to be complete and the hanger/packer  24  set to the casing  10  as a result of the conclusion of the expansion. It should be noted that the uphole oriented expansion of  FIG. 10  does not occur against cement  76  already in annulus  34 . Rather, expansion continues once the extended swage assembly  42  reaches the location  77  which marked the end of expansion. The assembly  36  can now come all the way out of the liner  20 . The shoe  26  can now be drilled out and more hole can be drilled. 
         [0069]      FIG. 12  begins another embodiment for a well with casing  100  and an open hole portion  102  terminating in a pilot hole  104 . In  FIG. 13  a liner string  106  is supported from a rig  108 . At the bottom of the liner  106  is a float shoe  110  with a one way valve  112  and lateral exits  114 . The float shoe  110  has a seat  116  for landing a plug as will be later described. A latch assembly  118  releasably holds the swage assembly  120  and the piston assembly  122  that controls the dimension of the swage assembly  120  to the float shoe  110 . Above the piston assembly  122  is one portion  124  of a latch assembly. Outside the liner  106  is a hanger/packer  126 . 
         [0070]      FIG. 14  shows a string  128  with another portion  130  of a connection that will seal and connect to portion  124 . Alternatively, the running string  128  could deliver the piston assembly  122  and the swage assembly  120  with a latch below that engages the float shoe  110 . This engagement can be with a type HRD running tool sold by Baker Oil Tools or an equivalent. 
         [0071]      FIG. 15  shows the liner  106  lowered to the pilot hole  104  and circulation through string  128  out ports  112  and  114  and up through the annulus  133  as represented by arrows  132  and  134  as such lowering is taking place. A debris barrier  136  is at the top of liner  106  for the reason explained before. String  128  supports the liner  106  near its lower end using latch assembly  118 . 
         [0072]      FIG. 16  shows that circulation has stopped and a plug  138  has been landed on seat  116  to allow pressure built up in string  128  to reach the piston assembly  122  so that its movement causes the swage assembly  120  move out to a larger dimension putting a bump out  142  in liner  106 . Further pressure buildup as shown in  FIG. 17  releases the latch connection  118  to the float shoe  110 . 
         [0073]      FIG. 18  shows pressure buildup against the plug  138  increasing the volume of chamber  144  as the swage assembly  120  continues to hold its enlarged dimension by virtue of continuous pressure on the piston assembly  122  schematically represented by arrow  140 . The uphole expansion is allowed to continue to a point below the bottom of the casing  100  but leaves the liner  106  expanded over substantially its entire length. 
         [0074]      FIG. 19  shows the string  128  lowered so that latch  118  is back inside float shoe  110  and secured and a follow on pressure buildup blows a passage through the plug  138  so that the assembly is ready for cementing as shown in  FIG. 20 . In  FIG. 20  cement  145  is delivered through passages  112  and  114  at a pressure that keeps the piston assembly  122  ports closed. After cement  145  is delivered to annulus  133  up to location  146  on the liner  106  representing where expansion stopped, a wiper plug  148  is landed on the now opened plug  138 . Optionally some cement  145  can be pumped above plug  148  to ease subsequent drill out as shown in  FIG. 20 . 
         [0075]    Once again pressure is built up from the  FIG. 20  position to cause latch  118  to release and to allow the swage assembly  120  held extended by piston assembly  122  that is now under pressure to be driven up through the already expanded portion to location  146  and then further up to the top of the liner  106 . The swage assembly  120  can optionally have a backup seal like a swab cup  150  shown in  FIG. 20  so that it can keep a seal while driven up to the location  146  where expansion will continue until the hanger/packer  126  is against the casing  100 , as shown in  FIG. 21 , and for continued movement until the entire liner  106  is expanded and all the expansion equipment is removed as shown in  FIG. 22 . At that point the float shoe  110  can be milled out. 
         [0076]      FIG. 23  starts an embodiment that tracks the previous embodiment only without cementing and instead using an open hole packer to seal the annulus around the expanded liner. As before a casing  200  is above an open hole  202  that is drilled or  204  if it is under-reamed. A rig  206  is at the surface  208 . As shown in  FIG. 24 , the liner string  210  has a hanger/packer  212  for eventual support and sealing contact with the casing  200  and one or more external open hole packers  214  such as for example FORMpac® or REPacker® sold by Baker Oil Tools. At the lower end of the liner  210  is a float shoe  216  with a one way valve  218  and side outlets  220  and a lower port  220 A. A latch assembly  222  is latched into the float shoe  216  for ultimate support of the liner  210  as will be explained below. Going uphole there is an adjustable swage assembly  224  with a piston operating assembly  226  and a connector profile  228 .  FIG. 25  illustrates a running string  230  with a connector  232  at its lower end adapted to contact connector profile  228  for a supporting and sealed connection to allow running in the liner  210  to the pilot hole  234  as shown in  FIG. 26 . As stated before for an alternative, the assembly that is above the float shoe  216  can be run into the liner  210  after the liner is assembled in the wellbore  202  or  204 . In  FIG. 26 , string  230  is used to lower liner  210  while circulation represented by arrows  236  and  238  flowing through lateral outlets  220  and lower port  220 A facilitate the advancement of the liner  210 . A debris barrier  240  prevents debris from entering the liner  210  during circulation as it is advanced into the wellbore. 
         [0077]    In  FIG. 27  a plug  242  is landed to allow pressure buildup in the string that is represented by arrow  244 , This pressure actuates the piston assembly  226  to increase the size of the swage assembly  224  and to create a bump out  246  in the liner  210 . As shown in  FIG. 28  further pressure increase and set down weight releases the latch assembly  222  so that the swage assembly  224  start being powered uphole with pressure and/or overpull. An optional seal such as a swab cup  248  could be used with the swage assembly  224  in the event that the swage assembly itself will not sufficiently seal against the liner it is trying to expand as better illustrated in  FIG. 29 . Also in  FIG. 29  the swage assembly is moved up the substantial length of the liner  210  with the result being that the open hole packer  214  is sealed against the open hole  202 . Multiple open hole packers can be run. Because there is no cementing in this embodiment, the swage assembly can be driven continuously until the hanger/packer is set against the casing  200  as shown in  FIG. 30 . The expansion equipment is removed as shown in  FIG. 31  out the top of the liner  210  and the float shoe  216  can be milled out. 
         [0078]    The remaining FIGS. focus on some applications of the techniques described above.  FIG. 32  shows a parent casing  300  and more hole drilled that can include under reaming as represented by  301  or simply an extension of the hole that is the size of the parent casing  300  as represented by the dashed line in  FIG. 32 . This view was previously illustrated in other FIGS. discussed earlier. 
         [0079]      FIG. 33  is a split view indication that liner  302  is hung off the casing  300  using a hanger/packer  320 . At the lower end is a shoe  303 . The view is split showing that liner  302  is sealed with cement  304  on the left or with an external packer or seal  305  on the right as an alternative. As another alternative the cement  304  and seal  305  can be used together. There can be one or more seals  305  employed. The packer  305  can seal either to the smaller or larger bore such as  301  depending on how the hole is drilled and which sealing device is used. 
         [0080]      FIG. 34  shows the liner  302  expanded and hung off the parent casing  300  and the shoe  303  drilled out with the annulus around the liner  302  isolated. More hole  310  is drilled which could be a straight bore or an under reamed bore as actually shown. 
         [0081]      FIG. 35  shows a second liner  311  through the expanded liner  302  and hung off the parent casing  300 . Although the liner  311  is shown cemented, it could also be in open hole without cement and it could be slotted. Alternatively it could be hung off liner  302  but hanging off the casing  300  allows a larger inside diameter for liner  311 . Additionally, the hanging of liner  311  from casing  300  allows for subsequent flow to be isolated from the expanded liner  302  which might have not have the required pressure capacity or corrosion resistance. The extension bore if under reamed allows lower circulation pressure when cementing the production liner  311 . The staging of the liners  302  and  311  allows different mud weights to be used to account for differing formation properties so as to avoid mud loss or formation damage during drilling and subsequent running of the string  311 . 
         [0082]      FIG. 36  shows a casing patch application where the casing  400  has a break or a crack or is otherwise damaged  401  and a section of tubular  402  can be inserted into position and expanded by the techniques described above so that pair of straddling seals  403  are disposed on opposed sides of the break  401 . Alternatively, longer continuous seals can be expanded to cover the damaged sections in place of straddling. Alternatively, the tubular  402  can be expanded into the inside wall of the casing  400  without seals such as  403  and simple expansion results in a tight seal that can be metal to metal. 
         [0083]      FIG. 37  illustrates an open hole patch application where additional hole  411  has been drilled past the casing  410  and in the open hole region there is a fluid loss zone, water or other undesirable fluid is being produced into the wellbore, and/or sloughing formation. The tubular patch  412  can be run in and expanded in the manner shown before with the use of external packers  413  to straddle the zone where the losses or unwanted inflow or sloughing is occurring. Alternatively, longer continuous seals can be expanded to cover the damaged sections in place of straddling. It should be noted that there may be a reduction in the drift diameter in the patch  412  as compared to the drift diameter of the casing  420  which will restrict the passage of bit and drill string assemblies, possibly leading to a smaller open hold being drilled below the open hole patch. However,  FIG. 38  is the same view as  FIG. 37  with the drilled hole  411  having been under reamed in the troublesome zone so that after expansion of the patch  412  to engage the seals  413  the drift diameter of the patch is at least as large as the drift diameter in the casing  420  and maintains the bit passage diameter for continuous drilling of the hole further. 
         [0084]      FIG. 39  starts another sequence of views with a cased hole  430  and an under reamed open hole  431  below it. In  FIG. 40  a liner  432  has been inserted and expanded to two diameters or possibly more diameters depending on the cone capabilities. The smaller diameter is in casing  433  and the larger diameter is in the under reamed open hole  431  below. As covered before, a shoe  434  can be run if cement  435  is the option selected or if the alternative of external packers  436  is used. In either even the shoe provides a seat as a part of the expansion process previously discussed. The inside dimension of the liner  437  in the open hole is at least as large as its inside diameter inside the casing  433 . In  FIG. 41  the shoe  434  is drilled out and additional hole  438  is drilled with a possible variation of the degree of under reaming which accounts for the dashed and solid line in the FIG. The innermost dashed line  439  represents the hole that would be made with the largest bit to fit through the top of the liner  432  while the next series of dashed lines represent under reaming to get the inside dimension of the lower end  437  of the same liner that had previously been expanded into an under reamed portion of the well above. The solid line represents a continuation of the bore size above.  FIG. 42  shows another tubular  440  which can be the production string inserted and optionally cemented with cement  441  although it could be left in open hole without cement. Essentially what will pass through the top  432  of the liner above can be used. Again the lower bore size depends on formation conditions and whether cementing is to be done. In  FIG. 42  the hole is under reamed to be about the size of the expanded portion  437  of the liner above. The string  440  is hung and/or sealed off inside the casing  442  but could optionally be hung off the bell portion  437  of the upper liner. The latter is illustrated in  FIG. 43  where the second liner  446  is expanded and hung and/or sealed off at  445  to the already expanded liner above and in the enlarged bell portion. The string  446  can be cemented  448  or sealed with external packers  447 . At the top, it can be hung from the bell of the previously expanded liner above using a hanger/packer  445 . Note that there is no reduction in drift size as between the smallest dimension of the liner above  432  and the expanded dimension of the string  446 . This is due to the lower string  446  being hung off in the bell of the liner above at hanger/packer  445 . 
         [0085]    In  FIG. 44  the upper and lower liners are expanded to two or more different dimensions. The lower liner is hung with hanger packer  452  in the bell of the liner above it. The lower portion  453  of the lower liner is flared out so that the choke points for flow are at the hanging areas of both liners and in each case there is no reduction of drift regardless how many strings are run and sequentially hung from the string above. Here again the option of cementing  455  or using an external packer or packers  454  is also illustrated. The process can be repeated to add additional expandable liners until depth is reached. Open hole production can be another option. 
         [0086]      FIG. 45  shows a progression of  FIG. 44  where the second liner  456  has been drilled out and the open hole  457  has been under reamed to accommodate another expandable liner. The third liner  458  is shown off bottom due to a collapse of the open hole  459 . Alternatively, the liner could become stuck in the open hole for a variety of reasons including differential sticking and fill. Although the third liner  458  did not reach its targeted depth, it is still able to be expanded in two or more dimensions, maintaining flexibility for further wellbore construction. The extended recess section length of the previous liner  456  accommodates the length that the third liner  458  is set high by means of a longer liner lap. It can therefore be seen that the extended recess diameter section of the previous liner increases the flexibility of operations and mitigates risk beyond that of a shorter recess length. If a shorter recess length were present in the second liner  456 , then the third liner  458  would not have been able to be expanded without restricting the pass through diameter. 
         [0087]      FIG. 46  is a further embodiment of the operational flexibility and risk mitigation provided by the extended recess diameter length. A third liner  460  has been installed into the wellbore below a second expandable liner  461 . The third liner  460  is shown in a no longer useable form as collapsed. Alternatively, the third liner could be leaking, not fully expanded, or otherwise damaged. Alternatively, the open hole below an undamaged third liner  460  could render the third liner unusable if for example the open hole stopped producing hydrocarbons, started producing water, or opened up for fluid losses. The sidetrack technique is then employed above the third liner  460  milling a window out of the side of the second liner  461  in a section that has been expanded to the recess diameter. After the window is milled the open hole section is further drilled and under reamed as required to accommodate running in a fourth liner  463  out of the window. The fourth liner is expanded in two or more dimensions and a hanger packer  462  is hung and/or sealed off in the recess diameter section of the second liner  461 . The section of the fourth liner  463  outside of the milled window in the second liner  461  is able to be expanded to the recess diameter. Open hole isolation for the fourth liner  463  is accomplished with cement  464  and/or the use of open hole packer or packers  465 . The bottom of the fourth liner  463  has been drilled out for further wellbore construction. All of the operational flexibility and risk mitigation provided by the two or more dimension expansion of the fourth liner and the recess resulting can be utilized in further wellbore construction such as: several additional Monobore liners are able to be run, ability to perform additional sidetracks, ability to set subsequent liners off of bottom, and running production strings of pipe to produce reservoirs without reducing the size of these production strings due to restricted pass through. 
         [0088]      FIG. 47  shows and upper casing  470  that has a bell at the lower end either in the condition installed or due to expansion into it of the first liner to be hung. In  FIG. 45  there is no liner in the hole but the FIG. is intended to be schematic of both ways a bell can be formed.  FIG. 48  shows a liner  473  hung with hanger/packer  472  in the bell of casing  470 . Again the shoe is used to expand the string  473  and to facilitate cementing  476  or use of an external packer or packers  475  or both or neither if production will occur from open hole.  FIG. 49  shows the shoe  474  drilled out and the hole  477  extended to the diameter of the expanded liner above. It can be under reamed to make it even larger should the formation characteristics and the cement delivery pressure be an issue. Running clearance could also be an issue that would warrant under reaming for running in of the liner  478  shown in  FIG. 50 . The production liner  478  can be cemented  479  or it can be in open hole without cement or sealed with external packers. The string  478  is hung off the smaller dimension of the casing above the bell where the upper liner is supported. As a result of two dimension expansion of the upper liner with the upper end in the bell of the casing and the upper wellbore under reamed, the resulting internal dimension to depth is not reduced and the use of the upper liner for staged completion of the well does not narrow the size of the production liner  478  which is dictated by the casing size where the production liner  478  is shown to be supported in  FIG. 50 . 
         [0089]      FIGS. 51-54  show a progression of the wellbore construction concepts shown in  FIGS. 47-50  in which the subsequent liner also contains a bell for the sake of being able to repeat the process multiple times without restriction of pass through.  FIG. 51  shows and upper casing  480  that has a bell  481  at the lower end either in the condition installed or due to expansion into it of the first liner to be hung. In  FIG. 51  there is no liner in the hole but the FIG. is intended to be schematic of both ways a bell can be formed.  FIG. 52  shows a liner  483  hung with hanger/packer  482  in the bell  481  of casing  480 . Again the shoe  484  is used to expand the string  483  and to facilitate cementing  486  or use of an external packer or packers  485  or both or neither.  FIG. 52  shows a bell section at the bottom of the liner  483  that is created either as a part of the process of expansion of this string or upon the installation of subsequent liner.  FIG. 53  shows the shoe  484  drilled out and the hole  487  drilled out and under reamed as above.  FIG. 54  shows the installation of a second liner  489  hung with a hanger/packer  488  in the bell of the previous liner. Zonal isolation is shown to be performed either with cement  492 , one or more open hole packers  490 , or both or neither. The second liner  489  contains a bell section  491  as the previous liner that can be used to hang off subsequent liners without restricting the wellbore. 
         [0090]    Those skilled in the art will appreciate that the various embodiments offer many advantages that include improved circulation from the lateral ports in the float shoe and a fast drill out from using soft materials for the float shoe. There is an ability to transmit torque through the liner string as it is being advanced right down to the float shoe. Using an adjustable swage removes the need for a bell portion in the liner assembly reducing surge/swab effects. The liner is substantially expanded prior to cementing making for a smaller volume to cement with shorter pump times and earlier compressive strength. The balance of the expansion to tie the liner to the casing is not done against cement. The adjustable swage also allows removal through the liner at any time should the full expansion of the liner become impossible for some reason. 
         [0091]    The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below.

Technology Classification (CPC): 4