Abstract: A method of expanding tubing downhole comprises providing a section of expandable tubing of a first diameter, and axially compressing the tubing to induce buckling, such that the buckled portion describes a larger second diameter. The resulting diametric expansion may be utilised to anchor or seal the tubing within a larger bore. The buckled portion may be used to anchor the tubing within the wellbore prior to expansion of the length of the tubing into the wellbore.

Abstract: A method of expanding tubing downhole comprises the steps of: providing tubing (14;44) of a first diameter; running the tubing into a bore (10;40); expanding a first section of the tubing to a second diameter, and expanding a second section of the tubing to a third diameter.

Abstract: The present invention provides an apparatus and method expanding a portion of a tubular. The expansion apparatus is run into a wellbore on a working string. The expansion apparatus first comprises a rotary expander for expanding an expandable tubular. The expansion apparatus further comprises a spline assembly for coupling the rotary expander to a motor disposed on the work string. The rotary expander and spline assembly have hollow bodies that allow them to encircle the work string and rotate relative thereto. The spline assembly comprises an inner sleeve and outer sleeve. The inner sleeve is attached to the motor and the outer sleeve is attached to the rotary expander. The inner and outer sleeves are coupled to each other using a spline and groove connection. The connection allows the rotary expander to be rotated by the motor, while at the same time, allow the rotary expander to move axially relative to the motor. The rotary expander comprises two rows of rollers for expansion against the tubular.

Abstract: An improved expansion assembly for an expander tool is provided. The expander tool is used to expand a surrounding tubular body within a wellbore. The expansion assembly first comprises a piston disposed within a recess of the expander tool. The top surface of the piston defines a bearing cavity configured to closely receive a roller. A shoe is further disposed on the top surface of the piston to receive a lower portion of the roller. In one arrangement, the roller is a tapered cylindrical roller actuated by hydraulic pressure applied from within the bore of the expander tool. Actuation of the tool forces the pistons to radially extend away from the body of the tool within the recesses. This, in turn, causes the roller members to engage the inner surface of the surrounding tubular body to be expanded. Rotation of the expander tool causes the rollers to at least partially rotate within the bearing cavity.

Abstract: The present invention provides an expandable tubular having improved polished bore receptacle protection. The present invention further provides methods for completing a wellbore through the use of an expandable string of casing having improved polished bore receptacle protection. In one aspect, the invention includes a liner member having an expandable section, and a polished bore receptacle positioned below the expandable section. The expandable section is run into a wellbore, and is positioned to overlap with the bottom portion of a string of casing already set within the wellbore. The expandable section is then expanded into frictional engagement with the surrounding casing. The expandable section optionally includes at least one sealing member and at least one slip member on the outer surface. In one aspect, a transition section is provided between the expandable section and the polished bore receptacle.

Abstract: Apparatus for injecting coiled tubing into a bore comprises a rotatable housing (28, 29) having an axis along which coiled tubing is to be translated. A set of rolling elements (12, 14) is rotatably mounted in the housing (28, 29), each rolling element (24) having a skewed axis of rotation with respect to the housing axis and being arranged for rolling contact with an outside diameter of the coiled tubing. The arrangement is such that rotation of the housing (28, 29) relative to the tubing causes the tubing to be moved axially through the rotating housing.

Abstract: An apparatus and methods for preventing the accumulation of unwanted materials in an enlarged inner diameter portion of a casing or housing. In one aspect of the invention, a sleeve is disposed in the housing to isolate an annular area defined by the outer surface sleeve and the wall of the enlarged inner diameter portion. The sleeve prevents unwanted materials from being disposed in the annular area. The sleeve can later be expanded into the enlarged inner diameter portion, removed from the wellbore or destroyed. In another aspect of the invention, the sleeve is provided and disposed to cover the enlarged inner diameter portion. By covering the enlarged inner diameter portion, unwanted material is prevented from accumulating at said portion and from interfering with the expansion of the next casing into said portion to form a monobore. The sleeve can be made from materials that are dissolvable, elastically deformable, or retrievable.

Abstract: A method of anchoring tubing in a bore comprises: providing first tubing having a section with a wall configured to provide outer surface portions describing a diameter less than a first diameter. The tubing is located within a bore comprising a first section having an internal diameter greater than the first diameter and a second section having an internal diameter corresponding to the first diameter, with the tubing section in the first section of the bore. The tubing section is then reconfigured such that the outer surface portions describe a tubing diameter greater than the first diameter. The tubing is then axially translated relative to the bore to locate the tubing section in the second section of the bore such that the outer surface portions are restrained to the first diameter by the bore, and the outer surface portions engage with the bore.

Abstract: A method of anchoring tubing in a bore comprising: providing tubing having a section with outer surface portions defining a tubing profile, and configured to describe an outer diameter less than a first diameter. The tubing is located within a bore having an internal diameter equal to the first diameter and defining a bore profile. The tubing is then reconfigured such that the tubing profile engages with the bore profile, anchoring the tubing within the bore.

Abstract: The present invention provides an expandable tubular having improved polished bore receptacle protection. The present invention further provides methods for completing a wellbore through the use of an expandable string of casing having improved polished bore receptacle protection. In one aspect, the invention includes a liner member having an expandable section, and a polished bore receptacle positioned below the expandable section. The expandable section is run into a wellbore, and is positioned to overlap with the bottom portion of a string of casing already set within the wellbore. The expandable section is then expanded into frictional engagement with the surrounding casing. The expandable section optionally includes at least one sealing member and at least one slip member on the outer surface. In one aspect, a transition section is provided between the expandable section and the polished bore receptacle.

Abstract: The present invention provides methods and apparatus for reducing friction and preventing galling between surfaces in a wellbore. In one aspect of the invention, mating threads are coated with fullerene to reduce galling of the threads during make up and break down. In another aspect, a fullerene is used between surfaces of an expansion tool and a tubular to be expanded in order to reduce friction and prevent galling therebetween. Preferably, the fullerene is a spherically shaped carbon 60 molecule otherwise known as buckyball or C60. The fullerene coating provides an intermediate surface between two metal surfaces, thereby preventing galling between the two surfaces. In another aspect of the invention, the fullerene is placed between the roller of an expander tool and the surface of the tubular to be expanded in order to reduce friction and galling.

Abstract: A method and apparatus for creating a seal between two coaxial strings of pipe are provided. 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. Multiple configurations of the expander tool are disclosed. 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 one embodiment, a seal ring 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.

Abstract: An apparatus and methods for preventing the accumulation of unwanted materials in an enlarged inner diameter portion of a casing or housing. In one aspect of the invention, a sleeve is disposed in the housing to isolate an annular area defined by the outer surface sleeve and the wall of the enlarged inner diameter portion. The sleeve prevents unwanted materials from being disposed in the annular area. The sleeve can later be expanded into the enlarged inner diameter portion, removed from the wellbore or destroyed. In another aspect of the invention, the sleeve is provided and disposed to cover the enlarged inner diameter portion. By covering the enlarged inner diameter portion, unwanted material is prevented from accumulating at said portion and from interfering with the expansion of the next casing into said portion to form a monobore. The sleeve can be made from materials that are dissolvable, elastically deformable, or retrievable.

Abstract: A method of expanding tubing downhole comprises providing a section of expandable tubing of a first diameter, and axially compressing the tubing to induce buckling, such that the buckled portion describes a larger second diameter. The resulting diametric expansion may be utilised to anchor or seal the tubing within a larger bore.

Abstract: A method of forming a seal between two tubular members (30,32) comprises providing a first tubular member (30) having an internal surface and an external surface describing a first diameter, with a recess (34) in the external surface at a seal portion of the first tubular member. A deformable circumferentially extending sealing member (36) is located in the recess, the sealing member describing an external diameter no greater than the first diameter. The first tubular member (30) is located within a second tubular member (32) and the seal portion of the first tubular member (30) is expanded such that the sealing member (36) engages an inner surface of the second tubular member (32).

Abstract: An improved expansion assembly for an expander tool is provided. The expander tool is used to expand a surrounding tubular body within a wellbore. The expansion assembly first comprises a piston disposed within a recess of the expander tool. The top surface of the piston defines a bearing cavity configured to closely receive a roller. A shoe is further disposed on the top surface of the piston to receive a lower portion of the roller. In one arrangement, the roller is a tapered cylindrical roller actuated by hydraulic pressure applied from within the bore of the expander tool. Actuation of the tool forces the pistons to radially extend away from the body of the tool within the recesses. This, in turn, causes the roller members to engage the inner surface of the surrounding tubular body to be expanded. Rotation of the expander tool causes the rollers to at least partially rotate within the bearing cavity.

Abstract: A downhole valve (10) comprises a body (12) defining a through bore (14) and a valve seat (16, 17); and a valve member (18) mounted in the body and moveable between positions to open and close the body bore (14). The valve member (18) defines a segment of a wall of a hollow sphere. In the open position the valve member (18) is located to one side of the bore (14) and in the closed position the valve member (18) engages the valve seat (16, 17).