Abstract:
Devices and methods for applying axial force for such uses as running and releasing tools or other articles within a wellbore. An installation system is described that includes a force generator used to generate axial forces. The installation system also releasably secures an article and is capable of releasing the article once it has been emplaced or installed with the force generator.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention generally relates to tools for use in installing articles and equipment within a wellbore. In some aspects, the invention relates to installation devices used in coiled tubing arrangements. 
         [0003]    2. Description of the Related Art 
         [0004]    When coiled tubing is used in wellbores, it is problematic to apply significant downward force on the tubing, as this might result in the collapse of or damage to the coiled tubing. This makes it difficult to perform many tasks wherein it is necessary to apply a downward force. One example of such a task is when a multilateral wellbore has been drilled wherein a primary, usually vertically-oriented wellbore has one or more lateral secondary wellbores which extend radially outwardly therefrom. It is difficult to apply set-down force for certain tools that are landed within the wellbore. Conventional arrangements for generating axial forces with coiled tubing assemblies lack the ability to be reused or to enable a device below the force generator to be actuated by hydraulic fluid pressure. 
       SUMMARY OF THE INVENTION 
       [0005]    The invention provides exemplary devices and methods for generating and applying axial force for such uses as running and releasing tools or other articles within a wellbore. An installation system is described that includes a force generator used to generate axial forces. The installation system also releasably secures an article and is capable of releasing the article once it has been emplaced or installed with the force generator. An exemplary installation system is described that includes an anchor for securing the system in place within a wellbore and a force generator in the form of a stroker tool for installing a diverter module that is run in with coiled tubing. The stroker tool creates the axial force needed to seat the diverter module within a lateral entry module in the wellbore. The installation system also includes a release tool that is selectively released from the diverter module after seating. 
         [0006]    The described stroker tool includes a tool body and a piston portion that is axially moveable with respect to the tool body in a telescoping fashion. The piston portion includes a mandrel with a central flowbore. A ball seat is releasably secured within the central flowbore by one or more frangible shear members that are designed to shear away at a predetermined level of fluid pressure within the central flowbore. The ball seat permits a ball or other object to be landed within the mandrel, permitting fluid pressure to urge the piston portion axially with respect to the tool body, thereby generating axial force. After the ball seat has been sheared out of the mandrel, hydraulic fluid pressure can be communicated through the stroker tool and to the release tool. The fluid pressure actuates the release tool to release from the seated diverter. 
         [0007]    The installation system also functions to provide physical indications to operators at the surface of the status of the installation operation. The running string can be pulled up on after the setting of the anchor. The increased resistance to pull will indicate that the installation system is successfully anchored in place. A fluid pressure drop associated with shearing out of the ball seat will provide an indication that 1) the stroker tool has become fully stroked for seating of the diverter module and 2) fluid, pressure has been transmitted to the release tool in order to release from the seated diverter module. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The advantages and other aspects of the invention will be readily appreciated by those of skill in the art and better understood with further reference to the accompanying drawings in which like reference characters designate like or similar elements throughout the several figures of the drawings and wherein: 
           [0009]      FIG. 1  is a partial side, cross-sectional view of an exemplary tool installation system constructed in accordance with the present invention with system components being shown in an exploded manner. 
           [0010]      FIG. 2  is a side, cross-sectional view of an exemplary stroker tool used with the tool installation system of  FIG. 1  and constructed in accordance with the present invention. 
           [0011]      FIG. 3  is a side, cross-sectional view of the tool shown in  FIG. 2 , now in a stroked condition. 
           [0012]      FIG. 4  is a side, cross-sectional view of an exemplary piston head used in the tool shown in  FIGS. 2 and 3 . 
           [0013]      FIG. 5  is a side, cross-sectional view of an exemplary insert sleeve used with the piston head shown in  FIG. 4 . 
           [0014]      FIG. 6  is a side, cross-sectional view of an exemplary ball seat and setting ball used with the insert sleeve shown in  FIG. 5 . 
           [0015]      FIG. 7  is a side, cross-sectional view of an exemplary release tool used with the tool installation system shown in  FIG. 1 . 
           [0016]      FIG. 8  is a side, cross-sectional view of the tool installation system of  FIG. 1  during run-in to install a diverter module within a lateral entry module in a wellbore. 
           [0017]      FIG. 9  is a side, cross-sectional view of the tool installation system of  FIG. 8  during installation of the diverter module. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]      FIG. 1  illustrates an exemplary installation system, generally shown at  10 , that has been constructed in accordance with the present invention. In the described embodiment, the installation system  10  is useful for installing an article within a wellbore wherein the article needs to be seated within a generally complimentary seating arrangement by applied axial force. In the described embodiment, a diverter module is emplaced within a lateral entry module that is already positioned within a wellbore. The components of the installation system  10  are shown in side view and partially exploded. The installation system  10  is shown here in conjunction with a lateral diverter module  20  which will be installed into a wellbore in a manner which will be described in detail shortly. 
         [0019]    The system  10  and the attached diverter module  20  are run into a wellbore on the tubing string  22 , which extends downwardly from the surface of a wellbore. Preferably, the tubing string  22  is a coiled tubing string of a type known in the art. The tubing string  22  defines a central internal flowbore, as is known in the art, through which hydrocarbon production fluid can be transmitted to the surface of the wellbore  10  from the diverter module  20 . In addition, fluid may be pumped downwardly through the tubing string  22  and pressure increased within the tubing string  22  using surface pumps, as is known in the art. Also, production arrangements and other tools can be passed through the flowbore of the tubing string  22 . The installation system  10  generally includes an anchor device  24 , a stroker tool  26 , and a release tool  28 . The diverter module  20  allows communication between the secondary bore  18  and the flowbore of the tubing string  22 . 
         [0020]    The anchor device  24  includes a sub body  30  with a plurality of slips  32  that are radially outwardly moveable with respect to the sub body  30 . In a currently preferred embodiment, the anchor device  24  is hydraulically actuated by fluid pressure within the tubing string  22 . When the anchor device  24  is actuated by increased fluid pressure, the slips  32  are moved radially outwardly and into biting engagement with a is surrounding casing. One suitable anchor device for this application is the Thru-Tubing Hydraulic Set Anchor (Model H13226) which is available commercially from Baker Oil Tools of Houston, Tex. 
         [0021]    The release tool  28  is used to convey the diverter module  20  into the wellbore and is capable of selectively releasing from the diverter module  20  after it has been latched into a pre-placed lateral entry module. The release tool  28  generally includes an outer housing  34 , an inner mandrel  36 , and a skirt  37  which carries engagement members in the form of latching collet fingers  38 . Although collet fingers  38  are depicted, different forms of latches, locks or other engagement members, as are known in the art, may be used. The skirt  37  and collet fingers  38  are axially moveable with respect to the outer housing  34 . An exemplary release tool  28  is depicted in  FIG. 7  apart from the other components of the system  10 , and it will be discussed in greater detail shortly. 
         [0022]    The stroker tool  26  is shown in greater detail in  FIG. 2 . As seen there, the tool  26  is a telescoping assembly that includes an outer tool body, generally indicated at  40  and a piston portion, generally shown at  42 , which is axially moveable with respect to the body  40 . The tool body  40  includes a top sub  44 , a generally cylindrical outer housing  46 , and a bottom sub  48 . The top sub  44  includes an axial bore  50  with a threaded portion  52  so that the stroker tool  26  can be affixed to the anchor  24 . The top sub  44  is affixed by threaded connection  54  to the outer housing  46 . The bottom sub  48  is affixed to the outer housing  46  by threaded connection  56 . The outer housing  46  surrounds and defines a piston chamber  58 , which is bounded by the top sub  44  at the top end and by the bottom sub  48  at the lower end. The bottom sub  48  contains a central polished bore  60  and lateral vent channels  62 . The vent channels  62  provide fluid communication between the pressure chamber  58  and the surrounding annulus  64 . 
         [0023]    The piston portion  42  of the stroker tool  26  includes a piston head  66  and an affixed mandrel  68 . The components of an exemplary piston head  66  are shown in greater detail in  FIGS. 4 ,  5  and  6 . The piston head  66  has a piston body  70  with an outer radial surface  72 . The outer radial surface  72  carries a fluid o-ring seal  74  and a dynamic seal stack  76 . The piston body  70  has an interior bore  78  with an enlarged insert chamber  80 . The lower end of the insert chamber  80  has threads  82  so that the mandrel  68  can be affixed to the piston head  66 . A portion of the insert chamber  80  also has threads  84  so that an insert sleeve  86  can be affixed within the insert chamber  80 . 
         [0024]    An exemplary insert sleeve  86  is depicted in  FIG. 5 . The insert sleeve  86  has a sleeve body  88  that presents an outer radial surface  90  with threads  92 . Annular fluid seals  94  are carried on the outer radial surface  90 . Threads  96  are also formed on the outer radial surface  90  and are shaped and sized to be complimentary to the threads  84  of the piston body  70 . A ball seat bore  98  is defined within the sleeve body  88 . Threaded openings  100  are disposed through the sleeve body  88 . 
         [0025]    A ball seat  102  is secured within the ball seat bore  98 . A exemplary ball seat  102  is shown in  FIG. 6 . The ball seat  102  has a generally cylindrical body  104  which defines a central fluid passageway  106 . A seat portion  108  is formed at one axial end of the ball seat  102  upon which ball member  109  can rest. Threaded openings  110  are disposed through the body  104 . Shear screws  114  are disposed within the threaded openings  100  and  110  to releasably secure the ball seat  102  to the insert sleeve  86 . The shear screws  114  are frangible members designed to break away at a particular level of axial force applied to the ball seat  102 . 
         [0026]    Referring once again to  FIG. 2 , the mandrel  68  defines a central flowbore  112 . A baffle  116  is located within the flowbore  112 . In a currently preferred embodiment, the baffle  116  is a perforated plate which allows fluid to pass through, but which will capture the ball seat  102  and ball  109 . It is noted that, while a spherical ball is depicted for ball  109 , the ball  109  may take other shapes, such as a dart, plug or other object that will seat upon the ball seat  102  and substantially block fluid flow through the passageway  106  of the ball seat  102 . 
         [0027]    A compression spring  118  is disposed within the pressure chamber  58 . The compression spring  118  abuts the underside of the piston head  66  and the upper axial end of the bottom sub  48 . 
         [0028]    In  FIG. 2 , the stroker tool  26  has had ball  109  landed upon the ball seat  102 . Thereafter, fluid pressure is increased in the flowbore  50  above the ball  109 . In  FIG. 2 , the stroker tool  26  is in an axially retracted position.  FIG. 3  illustrates the stroker tool  26  in a stroked position wherein the piston portion  42  has been moved axially downwardly (i.e., “stroked”) with respect to the tool body  40 , compressing the spring  118 . The stroked position shown in  FIG. 3  is an axially extended position. Fluid within the pressure chamber  58  is expelled through the vent channels  62 . It is currently preferred that the tool  26  provide a stroke with a length from about 12 to about 18 inches. 
         [0029]    When fluid pressure within the flowbore  50  increases to the point where the shear forces exerted upon the shear screws  114  exceeds the shear capacity of those is screws  114 , the screws  114  rupture and release the ball seat  102  from the insert sleeve  86 . The ball seat  102  and ball  109  will fall downwardly through the flowbore  112  of the mandrel  68  and land upon the baffle  116 . When this occurs, fluid flow is permitted through the flowbore  112  and baffle  116 . Fluid pressure above the piston head  66  is reduced, and the compression spring  118  urges the piston portion  42  upwardly with respect to the tool body  40  until it is again in the position shown in  FIG. 2 . 
         [0030]      FIG. 7  illustrates an exemplary release tool  28  in greater detail. The release tool  28  includes a central axial flow passage  120  which is defined within a release tool body formed by the outer housing  34  and inner mandrel  36 . An annular spring chamber  122  is defined between the outer housing  34  and the inner mandrel  36 . Spring  124  resides within the spring chamber  122 . The spring  124  exerts axial force upon the skirt  37 , urging it axially downwardly with respect to the housing  34 . An annular pressure chamber  126  is formed between the skirt  37  and the inner mandrel  36 . A lateral flow path  128  extends from the central flow passage  120  to the annular chamber  126 . Fluid seals  130  help enclose the pressure chamber  126 . The skirt  37  and collets  38  are normally in the downward position depicted in  FIG. 7 , with the collets  38  being biased radially outwardly by the presence of shoulder  132 . When fluid pressure is increased within the flowbore  112 , the pressure is transmitted through the lateral flow path  128  and into the annular pressure chamber  126  causing the skirt  37  to move axially upwardly, compressing the spring  124 . When the skirt  37  is moved axially upwardly, the collets  38  are raised above the shoulder  132  and are freed to deflect radially inwardly into recessed area  134  on the mandrel  36 . As a result, the release tool  28  can, in this manner, release an affixed tool from the collets  38 . 
         [0031]      FIGS. 8 and 9  depict the tool installation system  10  being used to install a diverter module  20  into a lateral entry module  136  which has been previously installed within a primary wellbore  138 . The primary wellbore  138  has been drilled through the earth  140  and lined with casing  142 . A secondary lateral wellbore  144  extends from the primary wellbore  138 . 
         [0032]    The lateral entry module  136  includes a central, generally cylindrical body  146  which defines a central bore  148  (see  FIG. 9 ). A lateral window  150  is formed in the body  146  and provides fluid communication between the bore  148  and the secondary wellbore  144 . The bore  148  of the lateral entry module  136  includes a landing profile ( 152  in  FIG. 9 ), of a type known in the art. One suitable lateral entry module for use as the lateral entry module  136  is the H28906 lateral entry module which is available commercially from Baker Oil Tools of Houston, Tex. 
         [0033]    The diverter module  20  includes a diverter body  154  defining an axial bore  156  within. Collet latching recesses  157  (see  FIG. 1 ) are formed within the bore  156 . A landing latch  158  is formed on the radial exterior of the body  154  and is shaped and sized to latch into the landing profile  152  of the lateral entry module  136 . The diverter body  154  also presents a ramp surface  160  that permits access into the bore  156  of the diverter module  20  and attached tubing string  22 . 
         [0034]    In  FIG. 8 , the installation system  10  is being run into the primary wellbore  138  in the direction of arrow  162 . During run in, the collets  38  of the release tool  28  are secured within the collet latching recesses  157  of the diverter module  20  to secure the diverter module  20  to the tool installation system  10 . The lower end of the diverter module  20  will eventually enter the upper end of the central bore  148  of the lateral entry module  136 . When the landing latch  158  of the diverter module  20  encounters the landing profile  152  of the lateral entry module  136 , downward progress ends, and it now becomes necessary to apply downward force upon the diverter module  20  in order to seat the landing latch  158  into the landing profile  152  of the lateral entry module  136 . The end of downward progress of the tubing string  22  will indicate to operators at the surface that the application of downward force is needed. 
         [0035]    A ball (or dart, plug or other object)  109  is now dropped into the tubing string  22  and lands upon the ball seat  102  of the stroker tool  26 . Fluid pressure is now increased within the tubing string  22 , and this will cause the slips  32  of the anchor device  24  to move radially outwardly and into biting engagement with the surrounding casing  142 . The tool installation system  10  is now secured axially within the primary wellbore  138 . The increased fluid pressure within the tubing string  22  also causes the piston portion  42  of the stroker tool  26  to be moved downwardly with respect to the tool body  40 , as described previously. This downward movement will urge the diverter module  20  into seating engagement with the lateral entry module  136  as the landing latch  158  becomes seated within the landing profile  152 . Proper seating can be confirmed by pulling upwardly on the tubing string  22  to ensure that latching has occurred. Thereafter, fluid pressure is increased within the tubing string  22  until the ball seat  102  is sheared out of the surrounding insert sleeve  86 . The release tool  28  will initially remain affixed to the diverter module  20  because the shoulder  132  prevents the collets  38  from moving radially inwardly to release the diverter module  20 . 
         [0036]    However, once the ball seat  102  is sheared out, fluid pressure can be communicated below the stroker tool  26  and to the release tool  28 . Fluid pressure will is enter the central flow passage  120  of the release tool  28  and is transmitted via the lateral flow passage  128  into annular chamber  126 . The increased pressure within the chamber  126  will urge the skirt  37  axially upwardly with respect to the outer housing  34  and inner mandrel  36  and compress the spring  124 . The collets  38  can then retract into the recessed area  134  thereby disengaging the diverter module  20  from the release tool  28 . The tubing string  22  and tool installation system  10  can now be withdrawn from the wellbore  138 . 
         [0037]    The installation system  10  provides a number of physical indicators to surface operators of the installation process for the diverter module  20 . Once fluid pressure has been increased within the coiled tubing string  22  to set the anchor device  24 , the string  22  can be pulled up on at surface. Increased resistance to pull will indicate that the installation system  10  is successfully anchored in place. Also, once the ball seat  102  has sheared out of the surrounding insert sleeve  86 , fluid pressure within the tubing string  22  will drop as fluid is communicated through the stroker tool  26  and to the release tool  28  below. The drop in fluid pressure provides an indication that 1) the stroker tool  26  has become fully stroked to seat the diverter module  20  and 2) fluid pressure has been transmitted to the release tool  28  in order to release the installation system  10  from the seated diverter module  20 . 
         [0038]    It is noted that the emplacement of the diverter module  20  into lateral entry module  136  is merely an example of the utility of the system  10 . The installation system  10  may be used to emplace other articles within a wellbore. 
         [0039]    Those of skill in the art will recognize that numerous modifications and changes may be made to the exemplary designs and embodiments described herein and that the invention is limited only by the claims that follow and any equivalents thereof.