Abstract:
Herein disclosed is an expansion device comprising at least one expanding segment; an actuator; and a connector linking the at least one expanding segment to the actuator such that when the actuator is activated, the expanding segment expands or retracts. The actuator is propelled by hydraulic, pneumatic, or electric power. Also disclosed herein is a method expanding a portion of a tubular comprising providing an expansion device comprising at least one expanding segment, an actuator, and a connector linking the at least one expanding segment to the actuator such that when the actuator is activated, the expanding segment expands or retracts; and placing the at least one expanding segment inside the tubular.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable. 
       BACKGROUND 
       [0003]    1. Field of the Invention 
         [0004]    The present invention generally relates to an expansion device and its use thereof. More particularly, the present invention describes an expansion device that creates one or more centralizers as an integral part of a tubular. 
         [0005]    2. Background of the Invention 
         [0006]    The use of expandable tubing, liners and casing is a recent technological advancement in fluid production. The tubing is expanded to the inside diameter of the casing. Casing is also being expanded to larger diameters. This presents new problems. To minimize the expansion, the liner must be the maximum possible diameter and be lowered into the casing. 
         [0007]    The tubing or liners have attachments, such as seals and anchoring devices. The attachments must be protected from coming into contact with the casing and other equipment in the well. Centralizers equal to or larger than the attachments are needed to keep the tubing or liners from making contact with the casing. 
         [0008]    It is difficult to attach a centralizer to the tubing due to the clearance. Rubber or compressible material is applied that is slightly larger than the attachments. This rubber acts as centralizers and also protects the attachments. Since they are rubber, they will compress when the tubing rubs the casing, and the attachments will hit the casing wall. This will cause damage to the casing and tubing. If the tubing is scarred, it can split when expanded and the attachments can be damaged. After expanding, the rubbers become seals. 
         [0009]    In recent years, the use of expandable tubulars has become more common in the drilling and completion phases of well bore construction. In these phases, it is necessary to protect tubulars (e.g., casing, tubing, and/or seal bores) from scarring; and/or to protect sealing and anchoring devices; and/or to prevent the tubulars from being scarred while being run down hole. In some situations, it is desirable to preventing the tubulars from bending and/or egging when being handled. 
         [0010]    In some cases, due to the limits of expansion of the expandable tubulars (e.g., casings and tubings), the outside/outer diameter (OD) of the tubular is as close as possible to the inside/inner diameter (ID) of the wellbore or casing. Rubber rings and other devices are either molded or attached to the expandable tubular to act as centralizers and seals after the tubular is expanded. The rubber rings may also serve to keep anchoring devices (anchors) attached to the tubular from scarring the casing and/or seal bores. During the expansion process, the anchoring devices (anchors) are pressed into the casing and hold the tubular in place; and the rubber rings or other devices would function as seals. 
         [0011]    Because the OD of the tubing and seals and anchors is very close to the casing ID, if the tubing or seals touch the casing, the seals will compress below the tolerance of the anchors and damage the casing and/or seal bores. The anchors can also be dislodged causing more damage. In addition, the tubing and casing can be scared causing it to split. When the tubulars are being handled, because the tubular material has little memory due to the high carbon content, it often eggs out of shape when it is picked up by a sling. 
         [0012]    Accordingly, there is continuing need and interest to develop expandable tubulars/assemblies with improved centralizers and devices and methods for making such. 
       SUMMARY 
       [0013]    Herein disclosed is an expansion device comprising at least one expanding segment; an actuator; and a connector linking the at least one expanding segment to the actuator such that when the actuator is activated, the expanding segment expands or retracts. In some embodiments, the actuator is propelled by hydraulic, pneumatic, or electric power. 
         [0014]    In some embodiments, the at least one expanding segment is in the shape of a portion of a ring. In some embodiments, the at least one expanding segment is tapered. In some embodiments, the connector is a shaft. In some embodiments, the shaft is tapered. In some embodiments, the expansion device further comprises a tapered pull nut or wedge. In some embodiments, the expansion device further comprises a sizing ring. In some embodiments, the at least one expanding segment is placed inside of a tubular and the sizing ring is placed outside of the tubular. In some embodiments, wherein the inside diameter of the sizing ring is the diameter of the expanded portion of the tubular. 
         [0015]    Also disclosed herein is a method expanding a portion of a tubular comprising providing an expansion device comprising at least one expanding segment, an actuator, and a connector linking the at least one expanding segment to the actuator such that when the actuator is activated, the expanding segment expands or retracts; and placing the at least one expanding segment inside the tubular. 
         [0016]    In some embodiments, the method comprises activating the actuator such that the connector causes the at least one expanding segment to expand outward to create at least one complete ring or at least one partial ring on the tubular. In some embodiments, the at least one complete ring or at least one partial ring is configured to centralize the expandable tubular when the tubular is in use. In some embodiments, the at least one complete ring or at least one partial ring has the same diameter as the expandable tubular after the tubular is radially expanded in use. 
         [0017]    In some embodiments, the method comprises reversing the actuator such that the connector causes the at least one expanding segment to close. In some embodiments, the method comprises moving the expansion device to another location and creating another complete or partial ring on the tubular. 
         [0018]    In some embodiments, the method comprises placing a sizing ring outside of the tubular. In some embodiments, the inside diameter of the sizing ring is the diameter of the expanded portion of the tubular. 
         [0019]    In some embodiments, the expansion device is propelled by hydraulic, pneumatic, or electric power. In some embodiments, the at least one expanding segment is in the shape of a portion of a ring and is tapered. 
         [0020]    The present invention comprises a combination of features and advantages which enable it to overcome various problems of prior devices. The various characteristics described above, as well as other features, will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention, and by referring to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    For a more detailed description of the preferred embodiment of the present invention, reference will now be made to the accompanying drawings, wherein: 
           [0022]      FIG. 1  illustrates an expansion device, according an embodiment of this disclosure. 
           [0023]      FIG. 2  illustrates how an expansion device is placed inside a pipe/tubular, according an embodiment of this disclosure. 
           [0024]      FIG. 3  illustrates the use of a sizing ring placed outside of the pipe/tubular, according an embodiment of this disclosure. 
           [0025]      FIG. 4  illustrates an expanded tubular/tubing, according an embodiment of this disclosure. 
           [0026]      FIG. 5  illustrates the use of an expansion device, including a sizing ring, according an embodiment of this disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Overview. To prevent the damage, a centralizer is needed that does not cause any problem when the tubing is expanded. The centralizer disappears after expansion to maintain the continuity of the expanded tubing, liner or casing. 
         [0028]    To centralize an expandable tubular, at least a section of the tubular is enlarged to have a larger OD than the remainder of the expandable tubular, forming at least one complete centralizing ring or at least one partial centralizing ring (i.e., a complete ring of 360 degrees or a segment/segments thereof as a partial ring). When the tubular is being placed downhole, the centralizing rings (complete and/or partial) serve to centralize the tubular whiling minimizing scarring and protecting the seals and anchors. After the tubular is placed downhole and radially expanded, the centralizing ring will expand along with the remainder of the tubular and the expanded tubular will have the same diameter. In other words, these centralizing rings (complete and/or partial) function to centralize the expandable tubular and then disappear after the tubular is expanded. 
         [0029]    As used herein, the term “tubular” refers to any tubular parts or components, especially related to the oil/gas/water well applications and downhole processes. Examples of such tubulars include a casing, a liner, a screen, or a production tubing. 
         [0030]    As used herein, the term “seal” refers to any sealing component or sealing mechanism as known to one skilled in the art. For example, seals are made of rubber or rubber-like material, attached to a tubular. The seals are generally placed where necessary to perform a sealing function. In some cases, the seals have a thickness of from 1/16 inch to any required thickness. When a tubular is expanded, the seals are compressed, e.g., sealing the space between a casing and a tubing. 
         [0031]    As used herein, the term “anchor” refers to any anchoring component/aggregate or anchoring mechanism as known to one skilled in the art, used to hold a device in place. There are various types of anchors. The anchors are generally made of a material much harder than the tubular (e.g., tubing or casing). The anchors are attached to the tubular by cement or welded onto the outside of the tubular. In some cases, when a tubing is expanded, the anchors attached to the tubing are embedded in the casing and tubing, holding the tubing in place. 
         [0032]    In an embodiment, centralizing rings are produced from the inside of the tubular (or pipe or tubing). In some cases, the tubular is preheated before a centralizing ring is formed. To expand a tubular, power is needed to push or pull an expanding shaft, which power may be hydraulic, pneumatic, electric or any method of pushing or pulling. In an embodiment, hydraulic power is used. 
         [0033]    An expansion device of this disclosure comprises a segmented ring. An expanding segmented ring is placed in the pipe at the desired location of a centralizing ring. This ring is split in one or more places. The ring has a tapered bore in the ID. The bore is large at the front end, and small on the back end. The shaft has a large tapered fixture on the end. When the shaft is pulled into the segmented ring, the ring expands. This type of expanding may be done in several ways. A double tapered fixture or a screw type may be used. (A single taper type is shown in this disclosure.) 
         [0034]    In an embodiment, as illustrated in  FIG. 1 , the design of a hydraulic expander is shown. The expander or expansion device comprises a hydraulic actuator, pull shaft, tapered segmented ring and tapered pull nut or wedge. 
         [0035]    In an embodiment, as illustrated in  FIG. 2 , “Position  1 ” shows a pipe or liner to be expanded. The tapered pull nut is attached to a pull shaft that is attached to a hydraulic actuator. The pull nut is tapered and will expand the segmented ring outward as the tapered pull nut is pulled into it. The ring will expand until the tapered nut stops or uses the full taper. “Position  2 ” shows the pipe in position to be expanded. The pull nut is extended and the expanding ring is in closed position. Position  2  is determined by the engineering requirements of the centralizing rings in order to centralize the tubular when run downhole or to protect attachments on the tubular. 
         [0036]    In an embodiment, as illustrated in  FIG. 3 , a sizing ring is shown in place. The inside diameter of the sizing ring is the expanded diameter of the desired drift for the tubing or liner, as seen in the side view (top) and cross-section view (bottom). The bottom of  FIG. 3  also shows that the sizing ring is clamped together in place. 
         [0037]    In an embodiment, as illustrated in  FIG. 4 , the hydraulic actuator of the expander is actuated; and the shaft with the expanding nut is pulled into the expanding ring. The inside diameter is expanded outward until the outside diameter of the pipe reaches the inside diameter of the sizing ring. Then the actuator is reversed and the tapered nut retracts from the expanding ring. The segmented ring closes. The expanded outside diameter is to size. The sizing ring is removed and the process is ready to be repeated to form another centralizing ring. 
         [0038]    In an embodiment,  FIG. 5  illustrates the operation of the expander (or expansion device) and the setup for diameter and length changes.  FIG. 1  shows the design of an expansion device and  FIG. 5  illustrates its use to create/form a centralizing ring as described herein. 
         [0039]    In various embodiments, the expansion device is able to expand a centralizer (or centralizing ring) twenty feet into the pipe or further if necessary. For long distances, a roller or rollers are placed on the bottom of the expansion device. This keeps the expansion device from rubbing the pipe while the pipe is pulled over the expanding head. An expansion device 10 feet long is able to produce rings in any position up to 10 feet from the face of the pipe. 
         [0040]    In various embodiment, the expanding head is changeable to achieve the desired expansion diameter. For example, the pull nut is removed. The expanding ring is removed, along with the friction plate. The new fixtures are replaced in the reverse order. 
         [0041]    Method of Making Expandable Tubulars with Centralizing Rings. 
         [0042]    In an embodiment, a centralizing ring of this disclosure is made using hydraulic or mechanical fixtures. For example, an expansion device is placed in an expandable tubular (tubing or casing), at a first desired position. A sizing block (or sizing cap or sizing clamp) is attached to the outside of the tubular to insure the proper diameter of a centralizing ring is created. The expanding ring is then mechanically expanded until the sizing clamp stops the expansion. The expansion device is moved to another location and the process is repeated to create a second centralizing ring as needed/desired. In some cases, the expandable tubular is heated before the centralizing rings are created. In some cases, induction heating is used to heat the tubular before the centralizing rings are made. 
         [0043]    In some embodiments, the hydraulic actuator is anchored to a stand at the end of a roller conveyor system. The conveyor is lowered or raised, depending on the diameter of the pipe. The sizing ring fixture is fixed and placed over the sizing ring. The ring is opened and closed by hydraulic cylinders. The pipe is rolled in on a conveyor to the desired position. The sizing ring is closed and the actuator is actuated. The pipe is expanded. The sizing ring opened and the expanded area is inspected for size. The pipe is removed or moved to another position for another ring to be made. 
         [0044]    While preferred embodiments of this invention have been shown and described, modifications thereof can be made by one skilled in the art without departing from the spirit or teaching of this invention. The embodiments described herein are exemplary only and are not limiting. Many variations and modifications of the system and apparatus are possible and are within the scope of the invention. Accordingly, the scope of protection is not limited to the embodiments described herein, but is only limited by the claims which follow, the scope of which shall include all equivalents of the subject matter of the claims.