High pressure high temperature packer system

Abstract

A method and apparatus for creating a seal between two coaxial strings of pipe. The method and apparatus have utility in one embodiment for sealing the annulus between the tubing and the casing within a hydrocarbon wellbore. According to the method of the present invention, an expander tool is positioned at a selected depth within the tubing, and then actuated in order to expand the tubing against the inner wall of the casing wall. The expander tool is rotated in order to provide a fluid seal in the annulus. In this way, the tubing string becomes its own packer. In the preferred embodiment, an elastomeric seal is provided around the outer surface of the tubing to enhance the fluid seal. Further, a slip ring is provided around the outer surface of the tubing to provide a gripping means between the tubing and the casing. In the preferred embodiment, rollers of the expander tool are aligned with the seal ring and slip ring before expansion.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to wellbore completion. More particularly, the invention relates to an apparatus and method for sealing a tubular in a casing.

[0003] 2. Description of the Related Art

[0004] Wellbores are typically formed by drilling and thereafter lining a borehole with steel pipe called casing. The casing provides support to the wellbore and facilitates the isolation of certain areas of the wellbore adjacent hydrocarbon bearing formations. The casing typically extends down the wellbore from the surface of the well to a designated depth. An annular area is thus defined between the outside of the casing and the borehole in the earth. This annular area is filled with cement to permanently set the casing in the wellbore and to facilitate the isolation of production zones and fluids at different depths within the wellbore.

[0005] It is common to employ more than one string of casing in a wellbore. In this respect, a first string of casing is set in the wellbore when the well is drilled to a first designated depth. The well is then drilled to a second designated depth, and a second string of casing, or liner, is run into the well to a depth whereby the upper portion of the second liner is overlapping the lower portion of the first string of casing. The second liner string is then fixed or hung in the wellbore, usually by some mechanical slip mechanism well-known in the art, and cemented. This process is typically repeated with additional casing strings until the well has been drilled to total depth.

[0006] Downhole tools with sealing elements are placed within the wellbore to isolate areas of the wellbore fluid or to manage production fluid flow from the well. These tools, such as plugs or packers, for example, are usually constructed of cast iron, aluminum or other alloyed metals and include slip and sealing means. The slip means fixes the tool in the wellbore and typically includes slip members and cores to wedgingly attach the tool to the casing well. In addition to slip means, conventional packers include a synthetic sealing element located between upper and lower metallic retaining rings.

[0007] The sealing element is set when the rings move towards each other and compress the element therebetween, causing it to expand outwards into an annular area to be sealed against an adjacent tubular or wellbore. Packers are typically used to seal an annular area formed between two coaxially disposed tubulars within a wellbore. For example, packers may seal an annulus formed between production tubing disposed within wellbore casing. Alternatively, packers may seal an annulus between the outside of the tubular and an unlined borehole. Routine uses of packers include the protection of casing from pressure, both well and simulation pressures, as well as the protection of the wellbore casing from corrosive fluids. Other common uses include the isolation of formations or leaks within a wellbore casing or multiple production zones, thereby preventing the migration of fluid between zones. Packers may also be used to hold fluids or treating fluids within the casing annulus.

[0008] One problem associated with conventional sealing and slip systems of conventional downhole tools relates to the relative movement of parts required in order to set the tools in a wellbore. Because the slip and sealing means require parts of the tool to be moved in opposing direction, a run-in tool or other mechanical device must necessarily be placed in the wellbore with the sealing tool. Additionally, the slip means takes up annular space that is limited. Also, the body of a packer necessarily requires wellbore space and reduces the bore size available for production tubing, etc. Additionally, high temperatures and pressures in a wellbore can create problems due to the degradation of the elastomeric sealing element or the corrosion of the moving parts in a conventional slip assembly.

[0009] Therefore, there is a need for a packer for sealing a downhole annular area which employs fewer moving parts. There is further a need for a packer which can be used to seal an annular area at high temperatures and high pressure differentials without experiencing physical degradation.

SUMMARY OF THE INVENTION

[0010] A packer is provided that can effectively seal or pack-off a tubing-casing annulus under elevated pressures and temperatures. The packer defines an expandable tubular body that is fixed and sealed within a wellbore by plastic deformation.

[0011] The packer is run into the wellbore as part of the production tubing string. The packer includes at least one elastomeric ring which is affixed to the outer surface of the tubular body. The sealing ring provides a seal between the tubular body and the casing that prevents production fluids from passing upwardly between the casing and the tubular. The packer further includes at least one slip ring, which is also affixed to the outer surface of the tubular body. The slip ring has a plurality of teeth that provide a gripping mechanism between the tubular body and the casing. In the preferred embodiment, the elastomeric ring is positioned above the slip ring.

[0012] Once the tubular body is expanded, the elastomer rings are sealed between the tubular and casing. The tubular body thus becomes a packer. In this manner, the production string acts as its own packer.

[0013] The packer is expanded by use of an expander tool. The expander tool is of a generally tubular nature, and employs pressure-actuated rollers which act against the inner surface of the tubular body in order to expand it against the casing. The rollers are movable from a first recessed position within the housing of the expander tool to a second extended position beyond the housing. In the preferred embodiment, the rollers have a unique multi-lobed surface contour that allows the uniform expansion of a tubular while reducing the potential of the tubular to crack.

[0014] A method is further provided for sealing an annulus in a wellbore. The tubular body to be sealed to the casing is first prepared by applying at least two bands around the outside of the tubular body. The bands are spaced a distance apart, with the first band serving as the sealing ring. The second band serves as the gripping band, and is known as the slip ring. This slip ring is positioned furthest down hole along the tubular and is the first to enter the wellbore casing. When the tubular body is expanded, the slip ring allows the tubular body to grip the wall of the casing while the sealing ring seals the tubular to the casing.

[0015] In practice, after the bands have been affixed to the tubular body, the tubular body is lowered into the wellbore casing. Once a desired depth has been reached, the expander tool is lowered into the wellbore casing on a working string. In one aspect of the present invention, the setting depth is located by a stop ring that has been previously installed in the production tubing

[0016] The expander tool is actuated by pumping fluid down the work string and into the expander tool until the pistons are forced radially away from the housing and the rollers come in contact with the walls of the tubular body. Simultaneously, the expander is rotated within the tubular. As hydraulic pressure is increased, the tubular body is expanded until the outer wall of the tubular body is in firm contact with the inner wall of the casing and the elastomer rings are compressed between the tubular body and the casing. The tubular becomes, in effect, a packer and eliminates the need for a separate packer device.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] So that the manner in which the above-recited features, advantages and objects of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.

[0018] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

[0019] FIG. 1 is a section view of a tubular body within a casing according to the present invention.

[0020] FIG. 2 is a perspective view of an expander tool according to the present invention. One of the roller assemblies is shown in an exploded state.

[0021] FIG. 3 is a cross-sectional view of the expander tool of FIG. 1 according to the present invention cut across one row of rollers. The rollers are shown in three different positions in this view. In P1, the roller is shown in its recessed position. In P2, the roller is shown in its expanded state. And in P3, the roller is shown in an exploded view.

[0022] FIG. 4 is a sectional view of the expander tool inside a tubular body. The rollers are in their recessed state within the plane of the expander tool body.

[0023] FIG. 5 is a section view of a tubular body partially expanded by an expander tool. The rollers are in their expanded state.

[0024] FIG. 6 is a cross-sectional view of a wellbore having a production tubing disposed therein. A tubular body within the production tubing has been expanded against the casing so as to form a packer. The expander tool is now being removed from the wellbore.

DETAILED DESCRIPTION

[0025] FIG. 1 is a partial sectional view of a packer 10 according to the present invention. The packer 10 defines a tubular body 202 placed in series with a string of production tubing 202. In the preferred embodiment, the tubular body 202 is simply a joint or portion of a joint of the production tubing 202 itself. However, it is within the scope of this invention to utilize a specially configured tubular body, such as a shorter and more malleable joint of pipe, for expansion into a string of casing 206.

[0026] The tubular body 202 is fabricated from a steel or metal alloy material. The material must be strong enough to withstand the high temperatures and pressure differentials prevailing within the downhole environment. However, it must be sufficiently malleable to be plastically deformed by expansion into the casing 206.

[0027] In the view of FIG. 1, the tubular body 202 has not been expanded. The tubular body 202 is disposed concentrically within a string of casing 206. For purposes of the present inventions, the term concentrically means that two tubulars have been positioned coaxially, with one residing within the other. The outer surface of the tubular body 202 is separated from the inner surface of the casing 206 by an annulus 204 to permit a clearance between the casing 206 and the tubular body 202 during run-in. The casing 206 is generally formed of steel, iron or a similar material and is typically cemented into the wellbore 208. A cemented annulus is shown at 220 in FIG. 1.

[0028] Affixed to the outer surface of the tubular body 202 is a plurality of bands 212 and 210. In the preferred embodiment for the apparatus of the present invention, the plurality of bands defines at least one sealing ring 212 and at least one slip ring 210. The sealing ring 212 is preferably fabricated from an elastomeric material, and provides a circumferential seal between the tubular body 202 and the casing 206 when the tubular body 202 is expanded against the casing 206. The seal ring 212 prevents production fluids from passing upwardly between the casing 206 and the production tubing 202 after the tubular body 202 has been expanded.

[0029] The slip ring 210 has a plurality of teeth 214 formed along its outer surface. The purpose of the slip ring 210 is to provide a gripping means between the tubular body 202 and the casing 206 upon expansion of the tubular body 202. The gripping teeth 214 are designed to grip the inner surface of the casing 206 and to prevent the tubular body 202 from slipping into the wellbore 208. In the preferred embodiment, the slip ring 210 is circumferentially disposed about the outer surface of the tubular body 202. However, it is within the scope of this invention to provide slip means of other configurations, such as a plurality of buttons (not shown) having carbide teeth, flame sprayed carbide aggregates, or other carbide-based gripping means.

[0030] In one aspect, the elastomeric seal ring 212 is spaced apart from the slip ring 210 on the outer surface of the tubular body 202. In the preferred embodiment, the seal ring 212 is positioned above the slip ring 210.

[0031] After the tubular body 202 is placed within the wellbore 208, it is expanded so that the seal ring 212 and slip ring 210 are in contact with the casing 206. Expansion is done through use of an expander tool, such as the expander tool 50 of FIG. 2. FIG. 2 is a partially exploded view of an expander tool 50. The expander tool 50 comprises a housing that supports a plurality of roller assemblies 101. The expander tool 50 includes a neck 104, a shoulder 106, a body 128 and a lower portion 130. The neck 104 has a threaded interior 122. The threads 102 extend along the length of the neck 104 and facilitate the connection of the expander tool 50 to a run-in string 302.

[0032] The shoulder 106 of the expander tool 50 is formed to coaxially align and connect the neck 102 to the body 128. In the embodiment shown, the body 128 is formed in a cylindrical shape with a plurality of apertures 108 formed therein. The apertures 108 are formed in two rows of three apertures 108 per row. The apertures 108 within each row are spaced equidistantly apart from each other, and the apertures 108 are generally co-planar to one another in a row. Other configurations of an expander tool 50 may be utilized for expanding a tubular body.

[0033] The apertures 108 receive the roller assemblies 101. The roller assemblies 101 include pistons 110 which move from a first recessed position within the apertures 108 to a second extended position. The roller assemblies 101 are shown in these two positions in FIG. 3. In position P1, the roller assembly 101 is shown in its recessed position. In P2, the roller assembly 101 is shown in its expanded state. The roller assembly 101 is also shown in an exploded view in P3.

[0034] As demonstrated in FIG. 3, the pistons 110 are coupled to outwardly facing rollers 114. The pistons 110 have a cylindrical shape with a seal 126 disposed on one end and a cup 116 formed in the opposite end. The pistons 110 are slidingly disposed in the apertures 108 first and are retained by a pair of retaining plates 118A and 118B. To prevent pistons 110 from falling out of the body 128, a pair of flats 144A and 144B are formed in the sides of the pistons 110. The flats 144A, 144B define a pair of flanges. The retaining plates 118A and 118B are fastened to the body 128 by socket head cap screws 120. When fully extended, the flats 144A, 144B abut the plates 118A and 118B. The cup 116 formed within the piston 110 accommodates a portion of the roller 114 that is rotatably affixed by an axle 112 into the cup 116. The axle 112 is disposed through an aperture 140A formed in the piston 110, then passes through a central bore 142 located in the roller 114 before being secured in a second aperture 140B formed in the piston 110.

[0035] Disposed throughout the center of expander tool 50 runs a conduit 122, seen in FIG. 3. The conduit 122 carries hydraulic fluid or mud to the pistons 110. The conduit 122 couples hydraulic fluid to the radial conduits 124 in order to apply pressure to pistons 110 and force them radially outward from the body 128.

[0036] The rollers 114, as seen in the perspective view of FIG. 1, have a contoured shape comprising three elliptical lobes 132, 136 and 138 (respectively top, center and bottom lobes) interspaced by two spacing sections 134A and 134B. In one embodiment, the roller 114 is formed from a single piece of material and has a bore 142 formed along its central axis. The top lobe 132 and the bottom lobe 138 are of similar proportions (diameter and radius), while the intermediate lobe 136 is smaller. Thus, a “bow-tie” shape is presented.

[0037] Advantages have been discovered incident to the use of a bow-tie profiled roller 114 over the more conventional “barrel” shaped roller (not shown). The bow-tie shape allows for a narrower point of contact between the roller surface 114 and the tubular 202 to be expanded. In this respect, less force is required to expand a tubular 202 at a single radial point than over an extended surface area. This, in turn, facilitates the transition within the tubular 202 from elastic deformation to plastic deformation. Thus, a tighter seal can be accomplished. The bow tie profile further allows for two separate points of radial contact, an upper 132 and lower 138 point, thereby doubling the seal contact points 402, 406. The intermediate roller point 136 aids further in the expansion of the tubular 202.

[0038] While the preferred embodiment for expansion of the tubular body 202 employs rollers 114 having a bow-tie profile, it is understood that other profiles may be employed for rollers 114. It is within the scope of this invention to utilize other roller shapes such as a “barrel” shape, for example (not shown).

[0039] In order to expand the tubular body 202 to form a packer 10, an expander tool, such as the expander tool 50 of FIG. 2, is run into the tubing string 12. The expander tool 50 is located at a depth adjacent the tubular body 202 to be expanded, as demonstrated in FIG. 4. To assist in the location of the expander tool 50, a positioning member 216 may optionally be employed within the tubular body 202. The positioning ring 216 is disposed within the interior of the tubular body 202. The positioning ring 216 is formed having an interior chamfer or bevel 218 along its inner diameter. This bevel 218 serves as a landing profile, and is used to land the expander tool 50 of FIG. 1 within the tubular body 202. The positioning ring 216 may be press-fit, welded or the like affixed to the interior surface of the tubular body 202, and is positioned below the slip ring 210. It is, however, within the scope of this invention to utilize other types of positioning members, or to use a locator in lieu of a positioning member.

[0040] The expander tool 50 is lowered into the tubular body 202 until the lower portion 130 abuts the bevel 218 of the positioning ring 216. The rollers 214 of the expander tool 50 are preferably aligned with the seal ring 210 and slip ring 212, respectively.

[0041] FIG. 4 is a partial sectional view of the expander tool 50 inside the tubular body 202 according to the present invention. FIG. 4 displays the expander tool 50 with the pistons 110 and the rollers 114 retracted within the perimeter of the body 128 as it would appear during run-in. FIG. 4 also depicts the mating relationship between the mating cone 130 and the positioning ring 216 when the expander tool 50 is positioned for use in the tubular body 202. The positioning ring 216 positions the pistons 110 and the rollers 114 into alignment with the bands 212 and 210. The expander tool 50 is lowered into the tubular body 202 by a run-in string of pipe 302 threaded to the neck portion 104 of the expander tool 50.

[0042] FIG. 5 is a section view of the tubular body 202 being expanded by the expander tool 50 according to the present invention. In practice, after the expander tool 50 has been lowered into the tubular body 202 at the end of run-in string 302 and aligned with positioning ring 216, hydraulic fluid or mud (not shown) is pumped from the fluid source through the string of pipe 302 into the body 128. A fluid source is shown schematically at 414. The fluid travels through conduits 212 into the piston apertures 108, forcing the roller assemblies 101 radially outward. As such, the pistons 110 move radially outward and rollers 114 come in contact with and begin to plastically deform tubular body 202. At the same time, the expander tool 50 is rotated from the surface of the well (shown schematically at 412) or by a mud motor (not shown), causing a series of annular rings 402, 404 and 406 to be initially formed along the interior surface of the tubular body 202.

[0043] The pumped fluid exits the expander tool 50 through one or more nozzles at the lower portion 130 of the tool 50. In the embodiment of FIG. 5, a single nozzle 152 serves as a sized orifice, and also as the outlet port for bore 122. As fluid is pumped through the nozzle 152, critical flow is reached. In one embodiment, the pistons 110 are actuated at the point of critical flow. As the hydraulic fluid is pumped through the central aperture 122, differential pressure created between the hydraulic fluid being pumped into the housing and the hydraulic fluid flowing through the housing out conduit 122 creates the radial forcing pressure on the pistons 110. As the rollers 114 create the annular rings 402, 404 and 406 within the interior surface of the tubular body 202, the exterior portion of the tubular body 202 is expanded outward toward the casing 206. The outward expansion of the tubular body 202 continues until seal ring 210 and slip ring 212 are compressed against the interior surface of the casing 206. Sufficient pressure is applied by the rollers 114 to create a contoured seal between the elastomeric ring 212 and the casing 206. Further, the pressure is enough to prevent slip ring 210 from moving within the casing 206.

[0044] To provide yet a greater seal between the tubular body 202 and the casing 206, the run-in string 302 may be translated vertically within the wellbore 208. This has the effect of lifting and lowering the expander tool 50 so as to expand an additional length of the tubular body 202. However, this additional step is considered optional by the inventors, and is not required when a bow-tie shaped profile is employed for the rollers 114.

[0045] After the tubular body 202 has been expanded and sealed within the casing 206, hydraulic pressure is removed or released. In one embodiment, a pressure differential causes the pistons 110 to be retracted into the body 128 of the expander tool 50 and allows the expander tool 50 to be removed from the tubular body 202. In another embodiment, the rollers 114 are braised inward with some brazens member.

[0046] After the expansion operation, the expander tool 50 can then be withdrawn from the wellbore 208 by pulling the working tubular 302. FIG. 6 is a cross-sectional view of a wellbore 208 having a production tubing 202 disposed therein, and showing an expander tool 50 being removed form the wellbore 208. The production tubing 202 has been expanded against the casing 206 so as to form a packer 10. The expander tool is now being removed from the wellbore 208. The production tubing 202 now functions as both a conduit for production fluids and also as an annular packer 10.

[0047] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

1. A method for sealing the annulus between two concentric tubulars disposed in a wellbore, the first tubular residing within the second tubular, comprising the steps of:

positioning an expander tool at the depth desired for sealing the annulus;

actuating the expander tool so that the expander tool acts against the inner surface of the first tubular;

expanding the first tubular so that the outer surface of the first tubular is in contact with the inner surface of the second tubular; and

rotating the expander tool so that radial contact is made between the outer surface of the first tubular and the inner surface of the second tubular, thereby creating a fluid seal in the annulus.

2. The method for sealing the annulus between two concentric tubulars of claim 1, further comprising the step of:

translating the expander tool vertically within the wellbore while expanding the first tubular so as to expand the first tubular along a desired portion of its length.

3. The method for sealing the annulus between two concentric tubulars of claim 1, wherein the first tubular is a tubular body in series with a string of tubing, and the second tubular is a string of casing.

4. The method for sealing the annulus between two concentric tubulars of claim 3, wherein the tubular body defines an elongated tubular member comprising:

a top end;

a bottom end;

at least one seal ring circumferentially fitted along the outer surface of the tubular body intermediate the top and bottom ends; and

at least one slip member disposed along the outer surface of the tubular body intermediate the top and bottom ends for gripping between the tubular body and the casing.

5. The method for sealing the annulus between two concentric tubulars of claim 4, wherein the seal ring is fabricated from an elastomeric material and serves to provide a fluid seal between the tubular body and the casing, thereby sealing the annulus.

6. The method for sealing the annulus between two concentric tubulars of claim 5, wherein the slip member defines a ring circumferentially fitted along the outer surface of the tubular body, and has a plurality of teeth to provide a gripping means between the tubular body and the casing.

7. The method for sealing the annulus between two concentric tubulars of claim 5, wherein the slip member defines a carbide material on the outer surface of the tubular body.

8. The method for sealing the annulus between two concentric tubulars of claim 5, wherein the tubular body further comprises a positioning member for positioning the expander tool at the proper depth within the tubular body.

9. The method for sealing the annulus between two concentric tubulars of claim 8, wherein the positioning member comprises a landing profile having a beveled member internal to said tubular body upon which the expander tool lands during the positioning step.

10. The method for sealing the annulus between two concentric tubulars of claim 5, wherein the tubular body defines a joint of production tubing.

11. The method for sealing the annulus between two concentric tubulars of claim 3, wherein the expander tool comprises:

a body having an upper portion and a lower portion;

a plurality of apertures disposed radially about the circumference of the body intermediate said upper and lower portions;

a piston disposed within each of said plurality of apertures; and

a roller coupled to each of said pistons, said roller having a plurality of lobes.

12. The method for sealing the annulus between two concentric tubulars of claim 11, wherein

said pistons are movable from a first recessed position essentially within said body, to a second extended position away from said body by a radial outward force applied from an interior of the body; and

said rollers are profiled to provide a top lobe, a bottom lobe, and an intermediate lobe, said top lobe and said bottom lobe having an essentially equal diameter which is greater than the diameter of said intermediate lobe.

13. The method for sealing the annulus between two concentric tubulars of claim 12, wherein

said expander tool further comprises a conduit internal to said body for transmitting fluid to said pistons so as to cause said radial outward force against said pistons; and

said body further comprises at least one nozzle through which fluid exits said body.

14. The method for sealing the annulus between two concentric tubulars of claim 13 wherein

said pistons further comprise two rows of three pistons per row where said pistons are disposed equidistantly about the circumference of the body; and

said plurality of rollers further comprises an axle coupling each of said rollers to each of said pistons.

15. The method for sealing the annulus between two concentric tubulars of claim 14 wherein the expander tool is sized to fit into the inner surface of the tubular body within the wellbore.

16. An expander tool for expanding a tubular body, the expander tool comprising:

a body;

a plurality of apertures disposed radially about the circumference of the body;

a piston disposed within each of said apertures; and

a roller coupled to each of said pistons, said roller having a plurality of lobes.

17. The expander tool of claim 16, wherein

said pistons are movable from a first recessed position essentially within said body, to a second extended position away from said body by a radial outward force applied from an interior of the body; and

said rollers are profiled to provide a top lobe, a bottom lobe, and an intermediate lobe, said top lobe and said bottom lobe having an essentially equal diameter which is greater than the diameter of said intermediate lobe.

18. The expander tool of claim 17, wherein

said expander tool further comprises a conduit internal to said body for transmitting fluid to said pistons so as to cause said radial outward force; and

wherein said body further comprises at least one nozzle through which fluid exits said body.

19. The expander tool of claim 18, wherein said pistons of said expander tool are movable by a radial force applied from an interior of the housing.

20. The expander tool of claim 19, wherein each of said nozzles defines an orifice sized so that said pistons are moved from said first recessed position to said second extended position when said fluid reaches critical flow through said nozzles.

21. The expander tool of claim 20 wherein

said pistons further comprise at least two rows of pistons, with a plurality of pistons on each row, and with said pistons being disposed equidistantly about the circumference of the housing on each row; and

said plurality of rollers further comprises an axle coupling each of said rollers to each of said pistons.

22. The expander tool of claim 21, further comprising a set of piston retaining plates disposed upon the body proximate each aperture in order to prevent over travel of said pistons.

23. The expander tool of claim 21, further comprising a rotational actuator coupled to said body for rotating said expander tool.

24. A method for sealing the annulus between a string of production tubing and the casing within a wellbore, comprising the steps of:

positioning an expander tool at a selected depth within the production tubing;

actuating the expander tool so that the expander tool acts against the inner surface of the production tubing;

expanding the production tubing so that the outer surface of the production tubing is in contact with the inner surface of the casing; and

rotating the expander tool so that radial contact is made between the outer surface of the production tubing and the inner surface of the casing, thereby creating a fluid seal in the annulus;.

25. The method for sealing the annulus of claim 24, wherein said production tubing comprises therein an expandable portion having:

at least one elastomeric seal ring circumferentially fitted along the outer surface of said expandable portion intermediate the top and bottom ends which provides a fluid seal between the expandable portion and the casing, thereby sealing the annulus;

at least one slip ring disposed along the outer surface of the expandable portion intermediate the top and bottom ends and spaced apart from the seal ring, the slip ring having a plurality of teeth to provide a gripping means between the tubular body and the casing; and

a landing profile having a beveled member internal to said expandable portion upon which the expander tool lands during the positioning step.

26. The method for sealing the annulus of claim 25 wherein the expander tool comprises:

a body;

a plurality of apertures disposed radially about the circumference of the body;

a piston disposed within each of said apertures, each of said pistons being movable from a first recessed position essentially within said body, to a second extended position away from said body by a radial outward force applied from an interior of the body;

a roller coupled to each of said pistons, each of said rollers being profiled to provide a top lobe, a bottom lobe, and an intermediate lobe, said top lobe and said bottom lobe having an essentially equal diameter which is greater than the diameter of said intermediate lobe; and

a conduit internal to said body for transmitting fluid to said pistons so as to cause said radial outward force.

27. The method for sealing the annulus of claim 26 wherein

said body further comprises at least one nozzle through which fluid exits said body;

said pistons further comprise two rows of three pistons per row where said pistons are disposed equidistantly about the circumference of the housing; and

said plurality of rollers further comprises an axle coupling each of said rollers to each of said pistons.

28. The method for sealing the annulus of claim 27, further comprising the step of translating the expander tool vertically within the wellbore while expanding the production tubing so as to expand the first tubular along a desired portion of its length.

29. A method of completing a wellbore comprising the steps of:

providing a tubular;

applying a slip ring around said tubular;

applying an elastomeric seal ring around said tubular proximate to said slip ring;

positioning the tubular into a casing of the wellbore;

positioning an expander tool in the tubular at a point proximate the slip ring and sealing ring;

applying hydraulic fluid internal to the expander tool; and

expanding, in response to the hydraulic fluid, portions of the tubular corresponding to the depths of the slip ring and sealing ring, whereby the tubular is placed into contact with the inner surface of the casing.

30. The method of claim 29, wherein the step of positioning an expander tool further comprises the steps of:

providing an expander tool having a plurality of multi-lobed rollers for forming a contoured seal, wherein said roller has a top, bottom and center lobes.

31. The method of claim 30 further comprising:

the step of rotating said expander within the tubular until said tubular is sealed to the inner surface of the casing.