Abstract:
A method and apparatus for running a liner into a well bore, hanging the liner to a casing, perforating the liner, cementing the liner in, setting a liner packer, and establishing sand control, all in one trip.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application relies upon U.S. Provisional Patent Application No. 60/550,686, filed on Mar. 5, 2004, and entitled “One Trip Perforating, Cementing, and Sand Management Apparatus and Method.” 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention is in the field of methods and apparatus used for cementing a liner in a well bore in an oil or gas well, and for subsequently performing other operations such as injecting into the well or producing hydrocarbons from the well. 
     2. Background Art 
     In the drilling and completion of oil and gas wells, it is common to position a liner in the well bore, to cement the liner in place, to perforate the liner, and to gravel pack the well bore, to allow the sand free production of hydrocarbons from the well or the injection of fluids into the well. These operations are typically performed in several steps, requiring multiple trips into and out of the well bore with the work string. As rig time is expensive, it would be advantageous to be able to perform all of these operations with a single trip into the well bore. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention provides a method and apparatus for running a combination tool into the well bore, including a liner with a hanger and packer, a perforation assembly, a landing assembly and float valve, and a setting assembly for installing the liner and cementing it in place. The setting assembly includes a liner hanger setting tool, a slip and button assembly, a swab cup assembly, and a gauge ring. The liner hanger, packer, perforation assembly, landing assembly, and float valve are all suspended from the liner hanger setting tool for lowering into the well bore. The perforation assembly can be any type of assembly adapted to provide access between the inner bore of the tool and the formation, either by the extension of telescoping perforation elements, or by the perforation of the cement layer in the annulus as is known in the art. 
     When the liner is at the desired depth, the flow through the landing assembly and the float valve is hydraulically shut off, and fluid pressure is used to set the liner hanger to suspend the entire assembly from the casing. Then, the setting assembly is hydraulically released from the liner hanger. If a telescoping perforation assembly is used, fluid pressure is used to extend the telescoping elements in the perforation section to contact the formation. Subsequently, fluid pressure shears a bull plug loose to re-establish flow through the float valve. Then, a stinger on the bottom of the setting assembly is landed in the landing assembly, at which time the gauge ring also completely extends any telescoping perforation elements which may not have fully extended under fluid pressure. 
     Cement is pumped through the landing assembly, out through the float valve, and up into the annulus between the liner and the formation. Where used, the telescoping elements preserve a plurality of fluid flow paths from the inner bore of the assembly to the formation, through the cement. Otherwise, the cemented annulus is perforated by known methods after setting of the cement. Pumpable darts below and above the cement can be used to segregate the cement from other fluids. The lower dart can shift an element in the landing assembly to establish cement flow around the dart, while the upper dart can close off the flow path which was established by the lower dart. Alternatively, instead of the fluid actuated landing collar, a standard drop-in-ball type landing collar can be used. 
     After the float valve is properly seated, the setting assembly can be lifted from the landing assembly, allowing packer setting dogs to extend outwardly over the top end of the liner packer assembly. Setting the setting assembly down on the top end of the packer assembly sets the packer to seal the annulus between the liner and the casing. 
     The novel features of this invention, as well as the invention itself, will be best understood from the attached drawings, taken along with the following description, in which similar reference characters refer to similar parts, and in which: 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIGS. 1A and 1B  are a section view of the apparatus of the present invention; 
         FIG. 2  is a section view of the liner hanger setting subassembly of the apparatus of  FIG. 1A ; 
         FIG. 3  is a section view of the hold down button and swab cup subassemblies of the apparatus of  FIG. 1A ; 
         FIG. 4  is a section view of the liner packer setting subassembly and gauge ring shown in  FIGS. 1A and 1B ; 
         FIG. 5  is a section view of a liner packer assembly which can be used with the present invention; 
         FIG. 6  is a section view of a liner hanger assembly which can be used with the present invention; 
         FIG. 7  is a section view of the landing assembly shown in  FIG. 1B ; 
         FIGS. 8 and 9  are section views of a portion of the landing assembly, showing the hydraulic shut-off operation; 
         FIG. 10  is a two position section view of a portion of the liner hanger setting subassembly, showing the hydraulic release operation; 
         FIG. 11  is a section view of the landing assembly, showing hydraulic extension of the perforation elements and re-establishment of the main bore flow; 
         FIG. 12  is a section view of the landing assembly and the liner packer setting subassembly, showing mechanical extension of the perforation elements and initiation of cement flow; 
         FIG. 13  is a section view of the landing assembly and the liner packer setting subassembly, showing completion of cement flow; 
         FIGS. 14 and 15  are detailed section views of a portion of the liner packer setting subassembly, showing extension of the setting dogs; 
         FIGS. 16 and 17  are detailed section views of a portion of the landing assembly, showing seating of the pumpable plug and establishment of bypass flow of cement; 
         FIG. 18  is a section view of the liner packer setting subassembly, showing setting of the packer; 
         FIG. 19  is a two position section view of the liner hanger setting subassembly, showing emergency release of the setting assembly from the liner hanger; 
         FIG. 20  is a section view of one embodiment of a telescoping perforation element which can be used with the present invention, shown in the retracted condition; and 
         FIG. 21  is a section view of the perforation element of  FIG. 20 , shown in the extended condition. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in  FIGS. 1A and 1B , the apparatus of the present invention includes a setting assembly  10  and a landing assembly  20 . A liner L is suspended from the setting assembly  10  by a liner hanger, with a perforation assembly  500  and the landing assembly  20  attached at the bottom of the liner L. Instead of the perforation assembly  500 , discussed in more detail below, another type of perforation tool, known in the art, can be used. The entire apparatus, including the liner L, is lowered through the casing C into the well bore. 
     The setting assembly  10  includes a liner hanger setting subassembly  100 , a slip and button subassembly  200 , a seal cup subassembly  300 , and a liner packer setting subassembly  400 . The landing assembly  20  includes a landing collar subassembly  600  and the float valve  700 . The liner hanger and liner packer, as commonly known in the art, are shown only symbolically in  FIG. 1A , between the liner L and the casing C. This apparatus is designed to lower the liner L into the well bore through the casing C, hang the liner L from the casing C with the liner hanger, release the setting assembly  10  from the liner hanger, lower the setting assembly  10  into the landing assembly  20 , pump cement into the annulus between the liner L and the formation, set the liner packer to seal the annulus between the liner L and the casing C, and withdraw the setting assembly from the well, all in one trip. Where a telescoping perforation assembly is used, the perforation elements are extended into contact with the formation before the cement is pumped. Otherwise, the cement layer is perforated by known methods after the cement sets. 
     As shown in  FIG. 2 , the liner hanger setting subassembly  100  includes a top connector  102  connected to a mandrel  104  with threads and one or more set screws. The mandrel  104  is in turn threadedly connected to a bottom connector  106 . A cylindrical torque finger holder  108  is attached to the outer surface of the top connector  102  by one or more shear screws  110 . The top end of the torque finger holder  108  has a serpentine profile as represented by the lower dashed line, and the outer surface of the top connector  102  has a similar profile, represented by the upper dashed line, designed to interlock with the serpentine profile on the top of the torque finger holder  108 , to transfer torque in the clockwise direction. The profiles on the top end of the torque finger holder  108  and on the outer surface of the top connector  102  are designed not to transfer torque in the counter-clockwise direction, thereby allowing selective shearing of the shear screw  110  as will be discussed below. 
     A hollow cylindrical collet housing  112  is suspended below the top connector  102 . The lower end of a cylindrical torque finger retainer  114  is attached to the inner surface of the collet housing  112  by splines and one or more set screws, and the upper end of the torque finger retainer  114  is bolted to the torque finger holder  108 . A plurality of outwardly biased torque fingers  116  are positioned in slots in the torque finger retainer  114 . The torque fingers  116  are biased outwardly into longitudinal slots in the inner surface of the liner hanger, as shown in  FIG. 1A . The torque fingers  116  and the aforementioned apparatus shearably connecting them to the top connector  102  are provided for the purpose of accomplishing an emergency release of the setting assembly  10  from the liner hanger, as will be described below. An outwardly biased collet  118  is attached to the collet mandrel  104 , by means of a collet piston  120  which is attached to the mandrel  104  by one or more collet piston shear screws  122 , and by means of one or more collet shear screws  124 . Interconnecting structure between the collet  118 , the collet piston  120 , and the mandrel  104  is described in more detail below. 
     As shown in  FIG. 3 , the slip and button subassembly  200  includes a slip mandrel  202  which is threadedly attached to a bottom sub  204 . A plurality of outwardly biased slips  210  are positioned around the outer surface of the slip and button subassembly  200 , to provide longitudinal positioning of the setting assembly  10  relative to the liner L. Attached to the bottom sub  204  of the slip subassembly  200  is the upper end of a seal cup mandrel  302  of the seal cup subassembly  300 . The lower end of the seal cup mandrel  302  is threadedly attached to a seal cup bottom sub  306 . A plurality of seal cups  304  are positioned around the outer surface of the seal cup subassembly  300 , to provide a pressure seal against fluid pressure below the seal cup subassembly  300 , in the annulus between the setting assembly  300  and the liner L. 
     As shown in  FIG. 4 , the liner packer setting subassembly  400  includes a packer setter body  402 , with a bottom sub  404  at its lower end. A cylindrical setting dog keeper  406  is shearably attached to the body  402  by one or more keeper shear screws  408 . A setting dog keeper skirt  412  is formed at the lower end of the dog keeper  406 , surrounding a plurality of packer setting dogs  414 . The packer setting dogs  414  are outwardly biased by a plurality of dog springs  416 , but they are held inwardly against the body  402  by the dog keeper skirt  412  when the dog keeper  406  is pinned in its lower position as shown. One or more packer setter ports  422  are provided through the wall of the body  402  from its inner bore to its outer surface, communicating fluid pressure to a chamber between the outer surface of the body  402  and the inner surface of the setting dog keeper  406 . A gauge ring  418  is mounted on the body  402  below the packer setting dogs  414 , and attached thereto with one or more shear screws. The outer diameter of the gauge ring  418  is only slightly smaller than the full inner diameter of the liner L. If the gauge ring  418  hangs up at any point in the process, the tool can be pulled free by shearing the shear screws. 
     A typical liner packer  800  is shown in  FIG. 5 , with a packer body  802 , and a setting mandrel  804  which is attached to the packer body  802  with one or more shear screws  806 . An expandable packer element  808  is provided around the outer surface of the packer  800 . A liner support profile  810  is provided on the inner surface of the packer body  802 . The collet  118  on the liner hanger setting subassembly  100  is outwardly biased into the liner support profile  810 . This supports the liner L from the liner hanger setting subassembly  100  by creating an interference fit, with the collet  118  being forced firmly into the liner support profile  810  by the weight of the liner L and a reactive upward force of a tapered upper surface on the bottom connector  106  of the liner hanger setting subassembly  100 . 
     As shown in  FIG. 6 , a typical liner hanger  900  is suspended below the packer  800 , including a hanger body  902 , a plurality of hanger slips  904 , and one or more hanger setting ports  906 , through the wall of the hanger body  902 . As is commonly known in the art, this type of liner hanger is set by applying sufficient fluid pressure through the ports  906  to shift one or more sleeves on the hanger  900  to wedge the slips  904  outwardly and downwardly against the inner surface of a casing. After the hanger  900  is set, the weight of the liner L applies additional outward force against the slips  904 , wedging them more tightly against the casing C. 
     As shown in  FIG. 7 , the landing collar subassembly  600  includes a landing collar body  602  which is attached below the telescoping perforation assembly  500 , which is discussed in more detail below. A liner section having a slightly increased inner diameter is provided between the perforation assembly  500  and the landing collar subassembly  600 . A stinger seat  604  is fixedly mounted to the inner bore of the landing collar body  602 , with a stinger seating profile  606  on its inner surface. Below the stinger seat  604 , a reduced diameter in the bore provides a dart seat  608 . At least one upper bypass port  612  above the dart seat  608 , and at least one lower bypass port  614  below the dart seat  608 , are provided from the inner bore to the annulus within the landing collar body  602 . A cylindrical indicating ring  610  is slidingly positioned to cover the upper bypass ports  612 , and held in place by one or more shear screws. 
     As seen in  FIGS. 7 and 8 , a middle connector  616  essentially isolates the upper annulus within the landing collar body  602  from the lower annulus. A shifting mandrel  618  is slidingly positioned to contact the inner surface of the lower end of the middle connector  616  and to extend down through the main bore of the landing collar subassembly  600 . Near the lower end of the shifting mandrel  618 , one or more flow ports  620  are provided through the wall of the shifting mandrel  618 . One or more orifices  622  are provided in fluid flow communication with the flow ports  620 , to allow fluid to flow from the main bore, through the flow ports  620 , through the orifices  622 , and through a plurality of longitudinal flow channels  634  in the orifice housing  662 , to exit the lower end of the landing collar subassembly  600 . The orifice housing  662  is held in place in the landing collar body  602  by a lock ring  644 . 
     The outer surface of the lower end of the middle connector  616  has mounted thereto an upper housing  642 , to which is connected a spring housing  650 , and a piston housing  648  therebelow. A seal sub  646  is connected to the lower end of the piston housing  648 , and the orifice housing  662  is connected to the seal sub  646 . A piston  628  is positioned between the piston housing  648  and the mandrel  618 , with the piston  628  being shearably pinned to the piston housing  648  by one or more shear screws  630 . A mandrel spring  632  is positioned between the spring housing  650  and the mandrel  618 , biasing the mandrel  618  upwardly. 
     The mandrel  618  is held in place in its lower position, shown in  FIG. 8 , by one or more balls  626  and a ball retainer  624 , interacting with the piston  628 . The ball  626  sits in a groove in the outer surface of the mandrel  618  and in a hole in the ball retainer  624 . A shoulder on the top end of the piston  628  extends over the ball retainer  624  and holds the ball  626  down in the groove in the mandrel  618 . The upper end of the ball retainer  624  is biased against the lower end of the spring housing  650 , preventing the ball retainer  624 , the ball  626 , and the mandrel  618  from moving upwardly. As will be discussed further below, a shifting port  652  is provided through the mandrel  618 , from the main bore to a chamber within the piston housing  648  above the piston  628 . 
     Below the mandrel  618 , a bull plug  636  is retained in place by one or more shear screws  638 , blocking the main bore. Below the bull plug  636  is a bull plug catcher  640 , with one or more main flow ports  654  therethrough. 
     The apparatus is assembled and lowered into the well bore, until the landing collar subassembly  600  and the perforation assembly  500  are at the desired depths. Then, as shown in  FIG. 9 , the fluid flow rate through the apparatus is increased, until backpressure created by the orifices  622  exerts enough pressure through the shifting port  652  to shear the piston shear screw  630  and drive the piston  628  down against the seal sub  646 . This allows the ball  626  to come out of the groove in the mandrel  618 , releasing the mandrel  618 . Bleeding off pressure then allows the mandrel spring  632  to drive the mandrel  618  upwardly, blocking off flow through the orifices  622 . An increasing pressure alerts the operator that the mandrel  618  has shifted. Alternatively, a standard drop-in-ball type landing collar could be used, instead of the illustrated fluid actuated landing collar. 
     As pressure increases, hydrostatic force via the hanger port  906  sets the liner hanger  900  to support the weight of the liner L from the casing C. Weight is set down with the work string to compensate for upward hydraulic force on the setting tool, until the collet  118  is essentially free from the weight of the liner L. The slip and button subassembly  200  assists in counteracting this upward hydraulic force. 
     The portion of  FIG. 10  above the centerline of the tool shows the tool in this weight-neutral condition. The collet  118  is still extending into the profile  810  in the liner, but the liner is not exerting weight on the collet  118 , or on the bottom connector  106 . Slack in movement of the collet  118  is absorbed by a collet spring  144  on a collet spring guide  142 . It can be seen in this Figure that the upper end of the collet  118  engages a split ring  140  and a collet retainer  138 . The upper end of the collet retainer  138  engages the lower end of the collet piston  120 , by means of a snap ring  126  and a snap ring retainer  128 . As mentioned before, the collet piston  120  is held in place up to this point by one or more shear screws  122 ,  124 . 
     After the liner hanger is set and the collet  118  is weight-neutral, pressure is further increased through a mandrel port  134  until hydrostatic pressure between a piston seal  130  and a mandrel seal  132  is sufficient to shear the shear screws  122 ,  124 . This drives the collet piston  120  upwardly, pulling with it the collet  118 , until the collet  118  pulls out of the liner profile  810  and up within the collet housing  112 , as shown in the portion of  FIG. 10  below the tool centerline. This releases the liner from the liner hanger setting subassembly  100 . A body lock ring  136  between the collet retainer  138  and the collet mandrel  104  holds the collet  118  in this position within the collet housing  112 . 
     Then, fluid pressure is further increased until the bull plug shear screws  638  are sheared, releasing the bull plug  636  to drop down into the bull plug catcher  640 , as shown in  FIG. 11 . This opens up flow through the main bore, through the main flow ports  654 , and out through the float valve  700 , by displacing the float valve ball  704  against the bias of the float valve spring  706  which tends to seat the ball  704  against the housing  702 . In the condition shown in  FIG. 11 , flow out the float valve  700  passes into the annulus and back up around the liner L. 
     Where a telescoping perforation assembly  500  is used, this increase in pressure also causes some or all of the telescoping perforation elements  504  on the perforation assembly  500  to extend to contact the formation F. Similar telescoping perforation elements are disclosed in U.S. Pat. No. 5,829,520, which is hereby incorporated herein by reference. 
       FIG. 20  shows one embodiment of such a telescoping perforation element  504  in the refracted position, while  FIG. 21  shows the telescoping perforation element  504  in the extended position. The element  504  can have one, two, or more tubular extensions  510 ,  512 , arranged in a telescoping fashion. The innermost end  506  of these extensions protrudes radially inwardly into the inner bore of the perforation assembly  500 , with the outermost end  508  of the extensions oriented radially outwardly. The interior  514  of the innermost extension provides a flow path for fluids. As seen in  FIG. 21 , when the element  504  is fully extended, the outermost end  508  contacts the surface of the formation F. As also shown in  FIG. 21 , the interior  514  of the element  504  can be filled with a sand control medium  516 , as disclosed, for example, in U.S. Pat. No. 5,829,520. Further, the sand control medium  516  can be retained in place as disclosed in U.S. Pat. No. 5,829,520. Or, the sand control medium can be retained within the element  504  by screens placed generally at the inner surface  506  and the outer surface  508 . The spaces between the sand control medium can be filled with a selectively removable blocking medium, as disclosed in U.S. Pat. No. 5,829,520. 
     After flow is established through the float valve  700 , the work string is picked up to make sure that the liner hanger setting subassembly  100  has released from the liner hanger. If it has not, the emergency release procedure is employed, as discussed below. If the hanger has released, the setting assembly  10  is lowered into the liner until the stinger or bottom sub  404  of the liner packer setting subassembly  400  is landed in the stinger seating profile  606  of the stinger seat  604  of the landing collar subassembly  600 , as shown in  FIG. 12 . As the setting assembly  10  is lowered, the torque transfer fingers  116  deflect inwardly against their biasing elements, collapsing the torque fingers  116  to the GD of the setting assembly  10 , thereby allowing the torque transfer fingers  116  to exit the longitudinal slots in the inner surface of the liner. During the lowering of the setting assembly  10 , the gauge ring  418  will mechanically extend any of the telescoping perforators  504  that did not fully extend hydraulically. The increased diameter of the liner section between the perforation assembly  500  and the landing collar subassembly  600  prevents fluid pressure under the seal cups from interfering with the seating of the stinger. 
     The cement is then pumped into the work string, with a pumpable dart  656  in front of, or below, the cement. A second pumpable dart  658  can also be pumped behind, or above, the cement, as shown in  FIG. 13 . When the lower dart  656  has landed in the dart seat  608 , as shown in  FIG. 12 , pressure is increased to release the liner hanger setting dogs  414 . As shown in more detail in  FIG. 14 , the setting dogs  414  are held in place by a top holding ring  420  and set screw  424 . The setting dogs  414  are held inwardly, against the bias of the dog springs  416 , by the skirt  412  on the lower end of the dog keeper  406 . The dog keeper  406  is held in place by one or more shear screws  426 . As shown in  FIG. 15 , as pressure increases between an upper o-ring  428  and a lower o-ring  430 , through the packer setter port  422 , the keeper shear screws  426  are sheared. This allows the dog keeper  406  to be forced upwardly by the hydrostatic pressure, until the keeper skirt  412  pulls away from the dogs  414 , allowing the dog keeper springs  416  to push the dogs  414  outwardly. Since, at this point, the packer setting subassembly  400  is still within the liner L, the dogs  414  will move out against the inner surface of the liner L. 
     Pressure is then further increased to open the upper bypass port  612 , as shown in more detail in  FIGS. 16 and 17 . That is, as pressure is increased on the upper bypass port  612 , this pressure eventually shears the indicating ring shear screw  660 , which releases the indicating ring  610  to be driven downwardly. This opens the upper dart bypass port  612  for cement flow, which passes through the annulus and back into the main bore through the lower bypass port  614 , thereby bypassing the lower dart  656  and providing an indication for the operator that the dart has seated and the bypass flow of cement has been established. If the upper bypass port  612  does not open, the pressure is increased until a blow out plug in the lower dart  656  is ruptured. When the upper dart  658  has seated against the lower dart  656 , this again blocks flow through the bypass ports  612 ,  614  or through the blow-out plug. 
     After completion of the cementing, the annulus surrounding the perforation assembly  500  is filled with cement, except for the flow paths provided by the telescoping perforation elements  504 , where the telescoping element type of perforation assembly is used. When the cement back pressure is being held by the float valve, the setting assembly  10  is pulled upwardly, until the packer setting dogs  414  are above the upper end of the packer  800 , and the dogs  414  are fully extended, as shown in  FIG. 18 . The setting assembly  10  is then set down on top of the liner, applying force to expand and set the packer  800 , as is commonly known in the art. The tool is then pulled from the well bore. Where a telescoping element type of perforation assembly is not used, the perforation assembly is used to perforate the liner and the cement, as is known in the art, after the cement sets. 
     As mentioned above, if the collet  118  fails to release from the liner profile  810 , the emergency release procedure is used. This is illustrated in  FIG. 19 , where the portion of the tool to the right of the centerline illustrates the emergency released position, and the portion to the left of the centerline illustrates the tool when the work string has been pulled upwardly to mechanically pull the collet  118  out of the liner profile  810 . The torque fingers  116  ride in longitudinal slots in the liner. Rotating the work string counterclockwise shears the shear screw  110 , allowing the top connector  102  to drop down relative to the liner, as shown in the right hand portion of  FIG. 19 . This moves the bottom connector  106  out of contact with the collet  118 . At the same time, the mandrel  104  is moved downwardly relative to the collet  118 , and the collet  118  is held in this new position on the mandrel  104  by the body lock ring  136 , shown in  FIG. 10 . Then, the work string is pulled upwardly, pulling the collet  118  out of the liner profile  810 , as shown in the left hand portion of  FIG. 19 . Thereafter, the setting assembly  10  is pulled from the well bore and the liner packer setting subassembly  400  is made up on the work string. The tool is then lowered to land the stinger in the landing collar subassembly  600 , pump cement, and set the packer, as discussed above. 
     While the particular invention as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages hereinbefore stated, it is to be understood that this disclosure is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended other than as described in the appended claims.