BACKGROUND OF THE INVENTION
Field of the Invention
This application is directed to a wireline deployable patch system for oil/gas wells and a method for deploying the system in an oil/gas well.
Description of Related Art
Methods and apparatus utilized in the oil and gas industry enable patching of wellbore casing in a borehole to isolate damaged areas such as leaking connections, corroded or damaged areas, etc. Many examples of patching techniques exist including patents, such as UK Pat. No. G82,525,830 owned by the assignee of the present invention. However, prior patching techniques may not be possible or desirable in some applications.
In some cases, the most economical and desirable method of installation of patches in wellbore casings may be deploying and setting the patch utilizing a wireline (WL). However, the length of the patch which can be deployed in the well on the WL is limited. The WL patch system consists of the patch section, the thruster section and the pump section. Due to lifting limitations and lubricator length limitations, all these together cannot exceed 70 ft of length. Thus, the maximum patch length that can be deployed in the well is approximately 40 ft.
Frequently, the length of a zone to be isolated may be significantly longer than 40 ft. The present invention provides a metal patch system and methods for deployment and installation of metal patches of any desirable length utilizing a wireline.
BRIEF SUMMARY OF SOME OF THE PREFERRED EMBODIMENTS
This invention overcomes the above deficiencies in the prior art by the provision of one or more extension patch sections that are connected between a bottom patch section and a top patch section. The top and bottom patch sections each include an anchoring/sealing element. The anchoring/sealing elements having internal diameters less than an internal diameter of the tubular may be expanded by a setting tool to secure the patch to an inner surface of the well, for example casing. The extension patch sections include tubulars with approximately the same inside and outside diameters as the bottom patch section tubular. The bottom portions of the extension patch sections have areas of reduced diameter with the outside diameter slightly less than the inside diameter of the bottom patch section tubular. The extension patch sections are deployed in the well on the setting tool such that their reduced diameter portions are positioned inside the upper part portions of the previous extension tubulars. The setting tool expands the reduced diameter portions to the diameter approximately equal to the inside diameter of the extension tubulars creating sealed connections between the extension tubulars. As a result, the metal patch of any desirable length may be constructed from limited length extension tubulars deployable and stackable on a wire line.
BRIEF DESCRIPTION OF THE DRAWINGS
For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:
FIG. 1 is a cross sectional view of a bottom patch section according to an embodiment of the invention;
FIG. 2 is a schematic view of a setting tool;
FIG. 3 is a showing of the setting tool coupled to the bottom patch section of FIG. 1;
FIG. 4 is a cross sectional view of a bottom patch section set in a wellbore;
FIG. 5 is a cross sectional view of an extension patch section according to an embodiment of the invention;
FIG. 6 is a showing of an extension patch section secured to a setting tool;
FIG. 7 is a cross sectional view of the extension section positioned such that its lower portion is positioned within the upper portion of the previous tubular section;
FIG. 8 is a cross sectional view of the bottom portion of the extension patch section being expanded and creating a connection with the bottom patch section within a casing;
FIG. 9 is a cross sectional view of the top patch section with a setting tool comprising two expansion cones;
FIG. 10 is a cross sectional view of the top patch section shown in FIG. 9 installed in the well;
FIG. 11 is a cross sectional view of an upper portion of a tubular comprising grooves;
FIG. 12 is a cross sectional view of a bottom portion of an extension patch section comprising an elastomeric sealing/anchoring element;
FIG. 13 is a cross sectional view of a bottom portion of an extension section comprising a metal sealing/anchoring element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
It is to be understood that the various embodiments of the present invention described herein may be utilized in various orientations, such as vertical, inclined, horizontal, etc., and in various configurations, without departing from the principles of the present invention. In the following description of the representative embodiments of the invention, directional terms, such as “above,” “top”, “upper” refer to a direction toward the earth surface along a wellbore, and “below,” “bottom,” “lower” and similar terms refer to direction away from the earth's surface along the wellbore.
Referring to FIG. 1, an embodiment of the bottom patch section 10 is a tubular 11 with an anchor/sealing element 12 coupled to the tubular. The anchor/sealing element 12 has an internal diameter 13 less than the internal diameter of the tubular 14. As shown in FIG. 2, a setting tool 20 includes a thruster 17 supported by a wire line 19 and an expansion device 15 such as a cone connected to the thruster via a shaft 16. As shown in FIG. 3 setting tool 20 is secured to the bottom patch section 10 such that expansion device 15 is position below the anchor/sealing element 12.
As shown in FIG. 4, the bottom patch section 10 is deployed to the desired location in the wellbore and set within the wellbore casing 27, by activating the thruster which provides upward movement of the expansion device 15 which radially plastically expands the anchor/sealing element 12 to be in interference contact with the inner surface of casing 27.
As shown in FIG. 5, an embodiment of the extension patch section 30 includes a tubular 21 with a reduced diameter lower portion 22 having an external diameter 23 slightly less than the internal diameter 14 of the bottom section or a previous extension section. The extension section 30 is secured to the setting tool 20 as shown in FIG. 6 with the expansion cone 15 positioned below the reduced diameter portion 22. Then, the extension section being secured to the setting tool is deployed in the wellbore and the reduced diameter portion 22 is positioned inside upper portion 8 of the bottom tubular 11 as shown in FIG. 7. Extension section is attached to the bottom patch section by activating the thruster 17 and moving the expansion device 15 through the bottom portion of the extension patch section 22 and expanding the internal diameter of the reduced diameter portion to the diameter approximately equal to the inside diameter of the extension tubular creating sealed connections between the tubulars, see FIG. 8. A plurality of extension sections may be connected to each other in a similar fashion.
As shown in FIG. 9 a top extension patch section 40 includes a tubular 32 having a reduced diameter bottom portion 22 with external diameter 23 less than the internal diameter 14 of the tubular 21, see FIG. 5, and an expandable anchor/seal member 33 coupled to the tubular 32.
The top extension section 40 is secured to the setting tool having expansion device comprising two expansion cones, one, 27, positioned below the reduced diameter bottom portion 22 and the other, 26, below the expandable anchor/sealing member 33, see FIG. 9. The use of expansion device with two expansion cones allows expansion of both bottom portion 22 and anchor/sealing element in one limited length stroke of the thruster. Then, the top extension section is deployed in the wellbore such that the bottom portion 22 of the top extension tubular 32 is positioned inside the upper portion 34 of the previously set extension tubular 33. The thruster 17 is actuated providing upward movement of the cones 27 and 26 and expanding bottom portion 22 into an upper portion of a lower positioned extension patch section tubular 33 as shown in FIG. 10. The upper cone 26 expands the expandable anchor/seal 33 such that anchor/seal 33 comes into interference contact with the inner surface of the well casing 27, thus anchoring and sealing the top patch section and providing zonal isolation along the whole cumulative length of the patch between the top and bottom anchor/seals.
Persons of skill in the art will recognize various combinations and orders of the above described steps and details of the methods presented herein. While this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications and combinations of the illustrative embodiments as well as other embodiments of the invention, will be apparent to person skilled in the art upon reference to the description. For example, to provide better sealing/anchoring engagement of the lower portion of extension patch tubular into the upper portion of the previous tubular, the upper portion 8 of the previous tubular may have grooves 42, see FIG. 11. Alternatively, the bottom portion of the extension tubulars may have an elastomeric coating, see FIG. 12 or plurality of anchoring ribs, see FIG. 13, or combination thereof. It is, therefore, intended that the appended claims encompass such modifications or embodiments.
The term anchor/sealing element when used herein includes a sealing element, an anchoring element, or the combination of a sealing and anchoring unit.