WO2016028298A1

WO2016028298A1 - Downhole anchoring apparatus

Info

Publication number: WO2016028298A1
Application number: PCT/US2014/052074
Authority: WO
Inventors: Mark ALLEY; Antonio GARZA; Wesley Don HEISKELL; Glen Robert PREAS; Robert Lee GONZALES; Bevy GILLIS
Original assignee: Viking Fishing And Oil Tools, Llc
Priority date: 2014-08-21
Filing date: 2014-08-21
Publication date: 2016-02-25

Abstract

An anchoring apparatus for engaging a borehole surface includes an anchoring member, an actuator, a fluid chamber, and an intensifier piston within a housing. The intensifier piston includes a first end having a surface area greater than a second, the second end being in communication with the fluid chamber, such that application of pressure to the first end applies a second pressure, greater than the first, to fluid in the chamber, which is in turn applied to the actuator to extend the anchoring member toward the borehole surface with intensified force. A second intensifier piston and fluid chamber can be included and used to apply intensified pressure to the actuator to retract the anchoring member. A movable mandrel within the housing can be used to physically apply a physical force to one or both intensifier pistons in place of or in addition to fluid pressure.

Description

DOWNHOLE ANCHORING APPARATUS

FIELD OF THE INVENTION

[001] Embodiments usable within the scope of the present disclosure relate, generally, to downhole apparatuses, e.g., for use in a borehole, and more specifically, to anchoring apparatuses usable to secure and/or support, temporarily or permanently, one or more tools or other objects at a selected location within a borehole or tubular structure.

BACKGROUND OF THE INVENTION [002] Conventional practices for securing and/or supporting tools and/or other objects (e.g., whipstocks) within a borehole at a desired downhole location include use of anchoring systems. Generally, a downhole anchoring system includes a tubular and/or cylindrical body, having anchoring members of some kind (e.g., slips or similar structures intended to frictionally grip and/or penetrate into adjacent surface) expandable and/or extendable from internal chambers within the anchoring system to a position external to the diameter of the anchoring system's body. Typically, an anchoring system is engaged with one or more tools or others object (e.g., attached above or below the anchoring system via a direct connection or via a string of one or more intermediate tubular members and/or other components or objects), and the anchoring system and engaged objects are lowered in the borehole to a desired depth/location. Once positioned, the anchoring system can be actuated and/or deployed, colloquially dubbed as "setting" the anchoring system, causing the anchoring members to extend outward from the anchoring system body to engage the borehole wall. Various types of anchoring systems and anchoring members can be used to engage a tubular string (e.g., a casing string) lining a borehole wall, or the native formation itself when deployed in an unlined (e.g., "open hole") region of a borehole .

[003] Actuation of an anchoring system typically causes the anchoring members to be forced against the borehole or tubular wall by advancing the anchoring members outward from the anchoring system body, usually at an angle, to contact the surrounding wall. Depending on the type of anchoring members used and the type of actuator used to extend and support the anchoring members, a combination of pressure, friction, and/or deformation of the borehole or tubular wall can serve to secure the anchoring system in a generally fixed position. Anchoring members are typically formed from materials harder than those of the contact surface against which they will be set, and the face (e.g., gripping surface) of the anchoring members can be provided with various shapes adapted to improve the grip of the member, prevent falling/sliding or rotation of the anchoring system, "bite" into and/or deform the borehole or tubular wall, frictionally engage the borehole or tubular wall, or other methods for limiting undesired movement of the anchoring system relative to the borehole or tubular structure wall .

[004] Conventional anchoring apparatuses are actuated using either mechanical or hydraulic means. Examples of direct mechanical actuation include biased springs, linkages, scissor-type expansion devices, "J" traveling mechanisms, and other similar mechanical means usable to displace anchoring members radially outward from the body of an anchoring apparatus to contact an adjacent borehole/tubular wall or other structure. Mechanically actuated anchoring apparatuses generally require placement of a stationary object, such as a packer or bridge plug, within a borehole prior to lowering the anchoring system and attached objects. When a portion of the mechanical actuator contacts the stationary object, the mechanical actuation process is initiated to engage the anchoring system with the borehole or tubular wall.

[005] Hydraulically actuated anchoring systems can be used to extend anchoring members outward from an anchoring system body using fluid-driven pistons and associated cylinders or similar means, actuated via fluid from a control line (e.g., in communication with an external source of fluid) , and are often preferred over mechanical alternatives, as hydraulic anchoring systems do not require placement of a stationary object to actuate the anchoring system, and may be designed to be readily retrievable from the borehole. However, the added potential efficiencies of hydraulically actuated anchoring systems occur at the cost of extending the anchoring members with a lesser force, resulting in a less secure engagement between the anchoring system and the adjacent borehole/tubular wall. Flow in a control line can be controlled remotely, e.g., using a remote device that operates using a variation in fluid flow and pressure of drilling mud in a well, such that when triggered (either manually, or automatically by various conditions), the anchoring members are extended outward to engage the borehole or tubular wall. Various means for moving the anchoring members can be used, including the direct application of fluid pressure through a tube or cylinder to move an anchoring member via flexible/inflatable bladders, and/or to move anchoring members along slopes, conical forms, ramps with incorporated springs, hinges, inclines, etc.

[006] A need exists for systems and methods that combine many of the advantages of both mechanical and hydraulic anchoring apparatuses, e.g., single-action actuation, load- resistance, torque-resistance, strength of engagement, and reliability of actuation without requiring placement of a stationary object to initiate the actuation process. BRIEF SUMMARY OF THE INVENTION

[007] Embodiments usable within the scope of the present disclosure include anchoring apparatuses useable to engage a borehole surface (e.g., a borehole wall and/or a surface of a tubular within a borehole) . One or more anchoring members (e.g., having grippers, slips, teeth, and/or other types of frictional and/or gripping surfaces) can be positioned within a housing, each anchoring member being movable between a retracted position within the housing and an extended position external thereto for engaging a borehole and/or tubular surface. An actuator (e.g., one or more fluid cylinders) can be provided in communication with the anchoring members and can be operable to move the anchoring members between retracted and extended positions.

[008] A first intensifier piston can be provided within the housing, a first end of the piston being in communication with a fluid source (e.g., a control line or similar conduit to a surface-based and/or downhole fluid source) and a second end being in communication with a first fluid chamber within the housing. The first end of the intensifier piston has a surface area greater than that of the second.

[009] In operation, fluid from the fluid source can apply a first pressure to the first intensifier piston to move the piston in a first direction. Movement of the piston applies a second pressure to fluid in the fluid chamber, at a second pressure greater than the first, and this second, greater pressure is applied to the actuator to cause the actuator to urge the anchoring member (s) toward the extended position.

[0010] A second intensifier piston can also be included within the housing, having a first end in communication with a pressure source and a second end in communication with a second fluid chamber within the housing. Upon application of pressure from the pressure source, movement of the second intensifier piston can apply an intensified pressure to fluid in the second fluid chamber, which can be applied to the actuator to retract the anchoring member (s) . In an embodiment, a mandrel can extend (e.g., longitudinally) through the housing and can be used to apply pressure to the second intensifier piston (e.g., by vertically moving the mandrel relative to the remainder of the anchoring system) . In a further embodiment, the mandrel can be used to apply a force to the first intensifier piston, e.g., to verify actuation and extension of the anchoring member (s) .

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The novel features believed characteristic of the disclosed subject matter will be set forth in any claims that are filed later. The disclosed subject matter itself, however, as well as a preferred mode of use, further objectives, and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: [0012] In the detailed description of various embodiments usable within the scope of the present disclosure, presented below, reference is made to the accompanying drawings, in which :

[0013] Figure 1 depicts a diagrammatic side view of an embodiment of an anchoring apparatus usable within the scope of the present disclosure, in a non-actuated position.

[0014] Figure 2 depicts the anchoring apparatus of Figure 1, shown in an actuated position.

[0015] Figure 3 depicts the anchoring apparatus of Figure 1, shown in a retracted position (e.g., subsequent to actuation thereof, and in a position suitable for retrieval) .

[0016] Figure 4 depicts a diagrammatic side view of an alternate embodiment of an anchoring apparatus usable within the scope of the present disclosure.

[0017] Figure 5 depicts a diagrammatic top view of the anchoring apparatus of Figure 2.

[0018] Figure 6 depicts a top, partial cross-sectional view of the anchoring apparatus of Figure 2.

[0019] Figure 7 depicts a diagrammatic side view of an upper portion of the anchoring apparatus of Figure 1. [0020] Figure 8 depicts a diagrammatic side view of a middle portion of the anchoring apparatus of Figure 1.

[0021] Figure 9 depicts a diagrammatic side view of a lower portion of the anchoring apparatus of Figure 1.

[0022] Figure 10 depicts a diagram illustrating an embodiment of a fluid system usable within the scope of the present disclosure.

[0023] Figure 11A depicts an isometric view of the anchoring apparatus of Figure 1, in a non-actuated position. [0024] Figure 11B depicts an isometric view of the anchoring apparatus of Figure 11A, in an actuated position.

[0025] One or more embodiments are described below with reference to the listed Figures.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[ 0026 ] Reference now should be made to the drawings, in which the same reference numbers are used throughout the different figures to designate the same components. [ 0027 ] Before describing selected embodiments of the present invention in detail, it is to be understood that the present invention is not limited to the particular embodiments described herein. The disclosure and description herein is illustrative and explanatory of one or more presently preferred embodiments of the invention and variations thereof, and it will be appreciated by those skilled in the art that various changes in the design, organization, order of operation, means of operation, equipment structures and location, methodology, and use of mechanical equivalents may be made without departing from the spirit of the invention.

[ 0028 ] As well, it should be understood the drawings are intended illustrate and plainly disclose presently preferred embodiments of the invention to one of skill in the art, but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views as desired for easier and quicker understanding or explanation of the invention. As well, the relative size and arrangement of the components may differ from that shown and still operate within the spirit of the invention as described throughout the present application.

[ 0029 ] Moreover, it will be understood that various directions such as "upper", "lower", "bottom", "top", "left", "right", and so forth are made only with respect to explanation in conjunction with the drawings, and that the components may be oriented differently, for instance, during transportation and manufacturing as well as operation. Because many varying and different embodiments may be made within the scope of the inventive concept (s) herein taught, and because many modifications may be made in the embodiments described herein, it is to be understood that the details herein are to be interpreted as illustrative and non-limiting. [0030] Figures 1 and 11A depict a diagrammatic side view and an isometric view, respectively, of an anchoring apparatus (100) usable within the scope of the present disclosure, in a non-actuated position, e.g., a configuration in which a plurality of anchoring members (of which a single anchoring member (12) is labeled for reference) are retracted to a position within the diameter of the anchor housing (14) (e.g., a cylindrical and/or tubular body having sufficient internal cavities for housing the internal components of the anchoring apparatus (100)), suitable for lowering the anchoring apparatus (100) and any attached/associated objects into a borehole. Figures 2 and 11B depict a diagrammatic side view and an isometric view, respectively, of the anchoring apparatus (100) in a deployed position, in which the anchoring members (12) have been extended beyond the diameter of the anchor housing (14) via actuation of hydraulic cylinders (16) associated with the anchoring members (12), e.g., to engage an adjacent borehole or tubular wall (not shown) . Figures 7, 8, and 9 depict magnified/detailed side, cross-sectional views of the top, middle, and lower portions of the anchoring apparatus of Figure 1, respectively.

[0031] The depicted anchoring apparatus (100) is shown having a central mandrel (2) that passes longitudinally through the approximate center of the anchor housing (14), the mandrel (2) having an upper portion extending above and through a top cap (3) . The upper portion of the mandrel (2) is shown having a thickness greater than the remainder thereof. The thinner portion of the mandrel (2) is shown extending longitudinally through an upper fluid intensifier piston (8), past the anchoring members (12) and hydraulic cylinders (16), and through a lower fluid intensifier piston (22) to terminate at a bottom cap (29) . The upper portion of the mandrel (2) or in some embodiments, anchor housing (14), can be engaged with adjacent objects (e.g., a whipstock or other downhole tools or systems), via internal or external threads or similar methods of connection. While the depicted mandrel (2) terminates at the bottom cap (29), it should be understood that in various embodiments, the mandrel (2) could extend beyond the lower end of the anchor housing (14), e.g., to engage adjacent objects located in a downhole direction from the anchoring apparatus (100) . While the mandrel (2) is shown as a single cylindrical member, it should be understood that a mandrel having multiple portions engaged to one another and any desired shapes and/or dimensions could be used, as well as components attachable to the mandrel (2), without departing from the scope of the present disclosure. Further, while a mandrel having an enlarged upper portion, relative to a thinner lower portion is depicted, any suitable dimensions and configurations could be used, depending on the dimensions, configuration, and/or arrangement of other components within the anchor housing (14) .

[0032] The top cap (3) can serve to contain and receive fluid through a control line port (4), shown in greater detail in Figure 7, and can be secured to the anchor housing (14) via studs, bolts, threads, pins or similar types of fasteners. Alternatively, embodied apparatuses could include a top cap integral with the body of the apparatus and/or associated therewith in any manner sufficient to prevent the passage of fluid between the top cap (3) and anchor housing (14) . The depicted top cap (3) is shown having a throughbore positioned at the approximate center thereof, sized to accommodate the upper portion of the mandrel (2) . In an embodiment, the bore of the top cap (3) can be sized to provide a close tolerance with the outer surface of the mandrel (2), with a sealing surface (6) therebetween.

[0033] A permeable retaining member (7), such as a snap ring, can be used to separate the enlarged upper region of the mandrel (2) from the upper face of the upper fluid intensifier piston (8), such that an upper fluid receiving cavity (9) is defined between the top cap (3), upper fluid intensifier piston (8), mandrel (2) and anchor housing (14), the cavity (9) being isolated from the remainder of the anchoring apparatus (100) and the region exterior thereto, except for communication with a fluid source via the control line (4) . In use, the upper fluid receiving cavity (9) can be pre-filled with fluid (e.g., water, oil, hydraulic fluid, drilling fluid, air, an inert gas or liquid, etc.) and placed in communication with an external fluid source (not shown), e.g., via the control line (4) . To apply pressure to the top face of the upper fluid intensifier piston (8), fluid from the external source can be flowed into the upper fluid receiving cavity (9) . In some embodiments, the external fluid source may flow fluid in excess of the volume containable and/or required by the upper fluid receiving cavity (9), in which case a vent port or valve (not shown) could be used to expel excess fluid (e.g., through the anchor housing (14) to the exterior of the anchoring apparatus (100) and/or to an adjacent chamber in the anchoring apparatus (100)). Alternatively or additionally, excess fluid could be collected in an accumulator, bladder (e.g., an inflatable bladder), or alternate chamber, e.g., within the anchor housing (14) and/or in fluid communication with the cavity (9) (e.g., positioned in an adjacent tool and/or object). Alternatively or additionally, fluid dispelled from the cavity (9) could be returned thereto, e.g., using suitable valves and/or conduits. [0034] An upper intensified fluid cavity (11) is defined beneath the lower face of the upper fluid intensifier piston (8), disposed about the mandrel (2) within the anchor housing (14) . The upper intensified fluid cavity (11) can be prefilled with a fluid (water, oil, hydraulic fluid, drilling fluid, air, an inert gas or liquid, etc.) The upper fluid intensifier piston (8) is depicted as a generally cylindrical object, having an upper end with a diameter greater than that of the remainder thereof. In the depicted embodiment, the diameter of the upper end of the upper fluid intensifier piston (8) has a close tolerance with the inner diameter of the anchor housing (14) at the location of the upper fluid receiving cavity (9) . The lower end of the upper fluid intensifier piston (8) is shown having a diameter that has a close tolerance with the inner diameter of the anchor housing (14) at the location of the upper intensified fluid cavity (11) . The length of the upper fluid intensifier piston (8) corresponds to the length between the breakable member (7) and the upper end of the upper intensified fluid cavity (11), such that when the top face of the upper fluid intensifier piston (8) abuts and/or is proximate to the breakable and/or destruct ible/degradable member (7), the lower end of the upper fluid intensifier piston (8) at least partially extends into the upper intensified fluid cavity (11), thereby isolating the upper intensified fluid cavity (11) from the upper fluid receiving cavity (9) . A lower space (5) is thereby defined beneath the enlarged upper end of the upper fluid intensifier piston (8), the outer diameter of the lower portion of the piston (8), the inner diameter of the anchor housing (14), and a shoulder of the anchor housing (14) at the upper end of the upper intensified fluid cavity (11) . In an embodiment, the lower space (5) can be prefilled with a fluid (water, oil, hydraulic fluid, drilling fluid, air, an inert gas or liquid, etc.) . An axial bore is shown extending through the approximate center of the upper fluid intensifier piston (8) for accommodating passage of the central mandrel (2), with a sealing surface (13) (e.g., a single, double, and/or multiple check seal) defined therebetween to prevent leakage of fluid along the mandrel. In an embodiment, sealing surfaces can also be provided between the outer surface of the upper fluid intensifier piston (8) and the inner diameter of the anchor housing (14) within the upper fluid receiving cavity (9) and/or the upper intensified fluid cavity (11) . [0035] The shape of the upper fluid intensifier piston (8) provides the piston (8) with a top face having a surface area greater than that of the bottom face thereof. In use, fluid pressure applied to the top face of the piston (8), via fluid pressure in the upper fluid receiving cavity (9) (provided via the control line (4)) can move the upper fluid intensifier piston (8) in a downward direction relative to the mandrel (2), anchor housing (14), and/or other portions of the anchoring apparatus (100) . Downward movement of the piston (8) can displace fluid in the lower space (5), e.g., through a low pressure passage (32, shown in Figure 7) to an accumulator (not shown), a vent port (not shown), and/or any other manner of chamber, cavity, or open portion within the anchoring apparatus (100) or an adjacent/associated object. Downward movement of the piston (8) can also displace fluid in the upper intensified fluid cavity (11), e.g., through a high pressure passage (34, shown in Figure 7), to actuate the hydraulic cylinders (16) and cause extension of the anchoring members (12) . Figure 1 depicts the upper fluid intensifier piston (8) and anchoring members (12) in a non-actuated configuration, while Figure 2 depicts the upper fluid intensifier piston (8) in a lowered/actuated position and the anchoring members (12) in an extended/actuated position. [0036] Due to the shape of the upper fluid intensifier piston (8) (e.g., having a top face with a surface area greater than that of a bottom face) , pressure applied to the top face at the upper fluid receiving cavity (9) that causes movement of the piston (8) results in an amplified and/or intensified pressure applied by the bottom face of the piston (8) to the fluid in the upper intensified fluid cavity (11) . As a result, the anchoring members (12), while actuated via hydraulic means, are extended with a significantly greater force than the force with which the anchoring members (12) would be extended if the pressure applied to the upper fluid receiving cavity (9) were provided in the absence of the upper fluid intensifier piston (8), enabling the anchoring apparatus (100) to function as a secure stationary and/or supportive member within a borehole. While Figures 1 and 2 depict an anchoring apparatus (100) having a single upper fluid intensifier piston (8) it should be understood that the principles illustrated herein could be applied to a series or parallel arrangement of fluid-intensifying pistons and/or plungers (e.g., multiple members in alignment and/or otherwise positioned in series, or parallel, each having an upper surface area larger than a lower surface area thereof) . The number and dimensions of the fluid intensifier ( s ) used can be varied depending on the dimensions and characteristics of a borehole and/or of the anchoring apparatus used.

[0037] In an embodiment, the permeable member (7) can be a breakable member and/or can include a movable and/or breakable portion. For example, to ensure that hydraulic pressure applied in the upper fluid receiving cavity (9) has properly set the anchoring apparatus (100), if proper setting thereof is uncertain and/or unverified, such as in the case when partial setting of the anchor is suspected, and/or if hydraulic actuation of the anchoring apparatus (100) is unsuccessful and/or damage and/or malfunction occurs or is suspected, a mechanical actuation of the upper fluid intensifier piston (8) can be performed. In one embodiment, the central mandrel (2) can be moved (e.g., manually from the surface of the borehole) , in a downhole direction, to displace and/or break the permeable member (7) and allow the enlarged upper portion of the mandrel (2) to impact and/or impart force to the top face of the upper fluid intensifier piston (8) . Any movement imparted to the piston (8) via manual/mechanical force can result in intensified force being applied to the fluid in the upper intensified fluid cavity (11), e.g., due to the difference in surface area between the upper and lower faces of the piston (8), and as such, mechanical /manual force can also be used to extend the anchoring members (12) and provide a secure engagement between the anchoring apparatus (100) and an adjacent surface and/or object.

[0038] Figure 5 depicts a diagrammatic, end cross-sectional view of the anchoring apparatus of Figure 2, taken across the top cap (3), illustrating the enlarged upper portion of the mandrel (2) centrally positioned within the anchor housing (14) . The control line (4) is visible extending through the top cap (3) to associate the upper fluid receiving cavity (9, shown in Figures 1 and 2) with an external source of fluid (not shown) . In the depicted embodiment, three anchoring members (12) are shown, generally equally spaced about the circumference of the anchor housing (14), in an extended position (e.g., extending beyond the outer diameter of the anchor housing (14) to engage an adjacent surface) . Figure 6 depicts an end, cross-sectional view of the anchoring apparatus of Figure 2, taken across a central portion thereof (e.g., just beneath the upper fluid intensifier piston (8)), in which a thinner portion of the mandrel (2) is visible, extending axially through the approximate center of the anchor housing (14), while the low pressure passage (32) and high pressure passage (34) are visible extending axially through the anchor housing (14), offset a distance from the center thereof. While the control line (4), low pressure passage (32), and high pressure passage (34) are conceptually illustrated as straight, vertical bores extending through the anchor housing (14), it should be understood that any manner of fluid path extending through and/or external to the anchoring apparatus could be used without departing from the scope of the present disclosure. Additionally, while Figures 7, 8, and 9 depict a single control line (4), low pressure passage (32), and high pressure passage (34) for illustrative purposes, it should be understood that any number and configuration of fluid pathways through the anchoring apparatus (such as one high pressure passage per anchoring member) could be used without departing from the scope of the present disclosure. However, in various embodiments, a single fluid passage could be used to supply fluid to multiple cylinders and/or other destinations (e.g., via cross or similar connector) .

[0039] Use of multiple, equally spaced anchoring members (12), as depicted, can facilitate centralization of the anchoring apparatus within a borehole and/or tubular string, e.g., due to contact between one or more of the anchoring members (12) and the adjacent wall and/or other contact surface urging the anchoring apparatus in the opposing direction. Additionally, however, in an embodiment, the anchoring apparatus can be adapted for non-uniform deployment of the anchoring members (12) . For example, when deployed in an irregular (e.g., non-cylindrical) borehole, such as an uncased bore through a native formation, each of the depicted anchoring members (12) could extend a different respective distance to contact and/or penetrate into an adjacent surface, and due to the hydraulic actuation method described above, each anchoring member (12) could securely engage the adjacent surface independent of the distance each respective anchoring member (12) was extended.

[0040] As shown in Figure 7, the control line (4) can extend through the body of the anchoring apparatus (e.g., through the top cap (3)) to communicate the upper fluid receiving cavity (9) with an external source of fluid (not shown) . A low pressure passage (32) can communicate with the lower space (5) beneath the upper fluid receiving piston (8) with an accumulator, vent port, or other receptacle (not shown) for the fluid therein. A high pressure passage (34) can communicate fluid from the upper intensified fluid cavity (11) to the hydraulic cylinders, responsive to movement of the piston (8), when actuated by increased fluid pressure in the upper fluid receiving cavity (9) . [0041] As shown in Figure 8, the high pressure passage (34) extends from the upper intensified fluid cavity (11, shown in Figure 7) to a hydraulic cross (13) or other type of connector and/or fitting usable to permit fluid flow and pressure to be divided/split and channeled into separate conduits. In the depicted embodiment, the hydraulic cross (13) can be used to flow fluid and pressure from the high pressure passage (34) to each of the hydraulic cylinders (16) via a respective high pressure hydraulic extension line (15) . One high pressure hydraulic extension line (15) is visible in Figure 8, extending from the hydraulic cross (13) to a hydraulic cylinder extension inlet fitting (35), which allows fluid and pressure from the line (15) to actuate a hydraulic piston (not shown) within the cylinder (16), which in turn actuates the piston rod (36) associated with the cylinder (16) to extending the anchoring member (12) beyond the diameter of the anchor housing, e.g., along an anchoring member guide track (30) . As described above, while Figure 8 shows a single high pressure passage (34) that flows fluid to a hydraulic cross (13), for splitting the fluid and/or pressure among multiple channels and/or flowpaths to actuate the individual cylinders, any number and configuration of passages between the upper intensified fluid cavity (11) and the cylinders (16) can be used without departing from the scope of the present disclosure. The guide track (30) is shown positioned at a constant incline angle, such that advancement of the anchoring member (12) therealong results in a gradual increase in contact and/or force between the anchoring member (12) and the adjacent borehole and/or tubular surface. The guide track (30) can be provided with any desired angle, depending on the whether a very gradual or more sudden approach of the anchoring member (12) toward the borehole and/or tubular wall is more suitable. The angle of the guide track (30) could range from a 90-degree angle (e.g., perpendicular to the longitudinal axis of the anchoring apparatus (100) and/or that of the borehole/tubular wall), to a very small incline, nearly parallel to the longitudinal axis of the anchoring apparatus (100), limited only by the possible placement of the hydraulic cylinders (16) to accommodate such movement.

[0042] By way of example, Figure 4 depicts a diagrammatic side view of an alternate embodiment of an anchoring apparatus (110) in which the hydraulic cylinders (16) and associated piston rods (36) are oriented generally perpendicular to the longitudinal axis of the anchor housing (14), such that the anchoring members (12), when actuated, would extend generally directly outward, e.g., perpendicular, to the body of the apparatus (110) . Other portions of the anchoring apparatus (110) shown in Figure 4 are substantially identical to the embodied anchoring apparatus (100) shown in Figure 1, and as such, have been provided with identical reference numerals. While Figure 1 and Figure 4 depict two exemplary configurations of anchoring members (12) relative to the anchor housing (14) and other portions of the respective anchoring apparatuses (100, 110), it should be understood that any arrangement adapted to extend the anchoring members (12) at any angle relative to any other portion of an associated apparatus and/or adjacent contact surface could be used without departing from the scope of the present disclosure.

[0043] Figure 8 depicts a retaining T-slot at the base of the anchor guide track (30) usable to retain the anchoring member (12) and/or cylinder, e.g., via engagement of a pin (18) within the slot. While the depicted T-slot suitably retains the anchoring member (12) in close proximity of the body of the apparatus (100), any manner of engagement between the anchoring member (12) and the remainder of the apparatus (100) that enables movement of the anchoring member (12) along an outward path away from the apparatus (100) (e.g., to engage an adjacent object) could be used without departing from the scope of the present disclosure.

[0044] Figure 8 depicts not only mechanisms by which the anchoring members (12) can be extended outward from the anchor housing (14), but also mechanisms by which the anchoring members (12) can be retracted (e.g., subsequent to deployment /setting thereof to enable retrieval of the anchoring apparatus (100) and/or one or more attached/associated tools or other objects). Specifically, Figure 8 depicts a high pressure passage (38) located below the cylinders (16) and anchoring members (12), opposite the high pressure passage (34) used to extend the anchoring members (12) . Fluid flowed through the lower high pressure passage (38) passes through a hydraulic cross fitting (39), then through high pressure hydraulic extension lines of which a single line (17) is shown for reference, then into the upper portion of the hydraulic cylinders (16) via an upper hydraulic cylinder extension inlet fitting (37) . Fluid entering the inlet fitting (37) can be of sufficient volume and/or pressure to move the cylinder piston toward its starting position, thereby retracting the piston rod (36) and associated anchoring member (12), such that the anchoring member (12) travels radially inward along the guide track (30), out of contact with the borehole and/or tubular wall, and within the circumference of the anchor housing (14) . Retraction of the anchoring members (12) to a position within the diameter of the anchor housing (14) can enable retrieval of the anchoring apparatus (100) and/or one or more attached tools or objects. [0045] With reference to Figure 9 and Figure 3, Figure 9 depicts the lower portion of the anchoring apparatus (100) shown in Figure 1, prior to retraction of the anchoring members (12), while Figure 3 depicts the anchoring apparatus (100) of Figures 1 and 2 after actuation of the lower fluid intensifier piston (22) to retract the anchoring members (12) . As shown in Figure 9, the central mandrel (2) passes through a bore in the lower fluid intensifier piston (22), with a sealing surface (27) defined therebetween, to terminate at a lower retainer (28) positioned within the bottom cap (29) . The depicted lower fluid intensifier piston (22) is similar in shape and configuration to the upper fluid intensifier piston, described previously, defining a lower intensified fluid cavity (21) above the upper face of the lower fluid intensifier piston (22), and an upper fluid space (19) defined beneath the enlarged lower end of the lower fluid intensifier piston (22), the outer diameter of the upper portion of the piston (22), the inner diameter of the anchor housing (14), and a shoulder of the anchor housing (14) .

[0046] In use, the lower fluid intensifier piston (22) can be moved in an upward direction, e.g., by mechanically and/or manually pulling the central mandrel (2) . Upward force on the mandrel can cause the lower retainer (28) to apply a force to the underside of the lower fluid intensifier piston (22), which can in turn cause upward movement thereof and the application of an intensified force (due to the smaller surface area of the top face of the lower fluid intensifier piston (22) versus that of the bottom face thereof) to fluid in the lower intensified fluid cavity (21), urging the lower fluid intensifier piston (22) to the position shown in Figure 3. Application of this pressure can force fluid from the lower intensified fluid cavity (21) through a lower high pressure passage (38), to the hydraulic cross fitting (39, shown in Figure 8) and cylinder inlet (37, shown in Figure 8) to cause retraction of the cylinders and associated anchoring members. While a single lower high pressure passage (38) is shown, communicating with a cross fitting (39), e.g., for separately flowing fluid from the passage (38) to multiple cylinders, in various embodiments, multiple passages through the body of the anchoring apparatus (e.g., one passage per cylinder) could be used without departing from the scope of the present disclosure. Movement of the lower fluid intensifier piston (22) can also force fluid from the upper fluid space (19) through a low pressure passage (40) to the exterior of the anchoring apparatus, a separate container, bladder, and/or accumulator, a separate chamber within the body of the anchoring apparatus, or combinations thereof. In an embodiment the lower fluid intensification cavity (21) can have a volume greater than that of the upper fluid intensification cavity (11, shown in Figure 7) to facilitate the creation of sufficient pressure and flow through the lower high pressure passage (38) to cause retraction of the cylinders and associated anchoring members. [0047] While the depicted embodiment includes means by which the anchoring members (12) can be retracted to enable retrieval of the anchoring apparatus, in various embodiments, an apparatus could be "locked" in a desired position, e.g., using linkages, "J" locks, drop-in pins, or other similar members. For example, in an open-hole operation, it is often desirable to permanently place an anchoring system using a locking mechanism.

[0048] To prevent undesired and/or unintended movement (e.g., longitudinal movement) of the mandrel (2) relative to the remainder of the anchoring apparatus (100), retaining members (31) can be used to removably and/or temporarily engage the mandrel (2) to the anchor housing (14) . For example, the mandrel (2) can be engaged to the lower retainer (28) via insertion of a pin (not shown), screw, rod, tube, or other type of connector in the orifice (20), such that movement of the mandrel (2) would cause similar movement to the lower retainer (28) . As described above, engagement of the lower retainer (28) to the mandrel (2) can enable the application of force (e.g., upward force) on the mandrel (2) to be applied to the lower fluid intensifier piston (22) via contact between the lower retainer (28) and the bottom face of the lower fluid intensifier piston (22). Additionally, Figure 9 depicts the lower retainer (28) removably engaged with the bottom cap (29) (which is, in turn, engaged with the anchor housing (14)), via the retaining members (31), which are depicted as spring-loaded ball detent assemblies. However, other types of retaining members, such as shearable pins, bolts, or other generally rigid objects usable to maintain a temporarily fixed relationship between the mandrel (2) and anchor housing (14) can be used without departing from the scope of the present disclosure.

[0049] As described previously, in an embodiment, downward force and/or movement of the central mandrel (2) can be applied to supplement the force provided by the hydraulic fluid to deploy the anchoring members (12) and/or to verify the successful actuation of the apparatus. The lower portion (26) of the mandrel can be configured to facilitate this movement and/or force without affecting or hindering a subsequent actuation to retract the anchoring members (12) . For example, the depicted lower portion (26) has a diameter equal to that of the remainder of the mandrel (2), excluding the enlarged uppermost region thereof. Just above the lower region (26), the throughbore (20), usable to receive a pin (not shown) , bolt, bar, tube, or other type of rigid object, is positioned. As described above, engagement of the lower retainer (28) to the mandrel (2) via the rigid object within the throughbore (20) enables upward force applied to the mandrel (2) to cause movement of the lower fluid intensifier piston (22), e.g., by applying a force to a ring member (24), which in turn transfers this force to the piston (22) . Similarly, engagement of the lower retainer (28) to the mandrel (2) causes downward force applied to the mandrel (2) to urge the lower retainer (28) in a downward direction. The depicted bottom cap (29) includes an orifice (e.g., an axial bore) having a diameter sufficient to accommodate downward passage of the lower retainer (28), such that application of a downward force to the mandrel (2) can lower the mandrel (2), the lower retainer (28), the connector within the throughbore (20), and the retaining members (31) (which can become temporarily disengaged from the bottom cap (29) during downward travel) . In an embodiment, the bottom cap (29) can be provided with a length sufficient to retain the retainer (28) internally for the full stroke/extension of the downward movement of the mandrel (2) and retainer (28) . The ring (24) can remain on top of and in contact /association with the retainer (28) during downward movement thereof. The lower portion (26) of the mandrel (2), the lower retainer (28), the ring (24), the rigid object within the throughbore (20), and the retaining members (31) can remain in a lowered/extended position, indefinitely, if desired, until upward force is applied to the mandrel (2), e.g., to actuate the lower fluid intensification piston (22) to retract the anchoring members (12) . Figure 9 further depicts a snap ring (25) between the bottom cap (29) and lower fluid intensification piston (22), engaging the anchor housing (14), e.g., to facilitate assembly of the apparatus .

[0050] Figure 10 depicts a basic hydraulic schematic diagram, illustrating an embodiment of a fluid system usable within the scope of the present disclosure. In the depicted embodiment, three hydraulic cylinders are shown, with two sources of intensified fluid pressure split into three fluid flows (one per cylinder) . It should be understood that other embodiments usable within the scope of the present disclosure could include additional fluid intensifiers, e.g., operating in series or parallel, a greater number of splits to flow fluid to a greater number of cylinders, or a smaller number of splits and/or cylinders.

[0051] As described previously, Figures 11A and 11B depict external views of the anchoring apparatus (100 and 110), shown in a non-actuated position (with the anchoring members retracted) , and an actuated position (with the anchoring members extended beyond the circumference of the anchor housing to contact a borehole or tubular wall), respectively. For illustrative purposes, Figures 11A and 11B depict the anchoring members, guide tracks, and hydraulic cylinders as exposed elements; however, in various embodiments, covers and/or removable/displaceable material can be provided over the exposed anchoring members and associated components, e.g., to minimize debris entering the body of the anchoring apparatus. Actuation of the anchoring apparatus (100) and anchoring members (12) can break, remove, displace, and/or otherwise overcome the covers. In other embodiments, use of covers can be omitted, and the actuation of the anchoring members (which exerts a significant force) can overcome debris within the path of the anchoring members.

[0052] While various embodiments usable within the scope of the present disclosure have been described with emphasis, it should be understood that within the scope of the appended claims, the present invention can be practiced other than as specifically described herein.

Claims

CLAIMS What is claimed is:

1. An anchoring apparatus for engaging a borehole surface, the apparatus comprising:

a housing; an anchoring member within the housing, wherein the anchoring member is movable between a retracted position within the housing and an extended position in which at least a portion of the anchoring member is positioned external to the housing for engaging the borehole surface;

an actuator in communication with the anchoring member and operable to move the anchoring member between the retracted position and the extended position;

a first fluid chamber within the housing and in communication with the actuator; and a first intensifier piston comprising a first end in communication with a fluid source and a second end in communication with the first fluid chamber, wherein the first end of the first intensifier piston comprises a surface area greater than that of the second end of the first intensifier piston, wherein fluid from the fluid source applies a first pressure to the first intensifier piston to move the first intensifier piston in a first direction, wherein movement of the first intensifier piston in the first direction applies a second pressure to fluid in the first fluid chamber, wherein the second pressure is greater than the first pressure, and wherein the second pressure applies force to the actuator to cause the actuator to urge the anchoring member toward the extended position .

2. The apparatus of claim 1, further comprising a mandrel extending longitudinally through the housing, wherein the mandrel is vertically movable relative to the first intensifier piston, and wherein contact between the first end of the first intensifier piston and the mandrel, a member attached to the mandrel, or combinations thereof applies a force to urge the first intensifier piston in the first direction .

3. The apparatus of claim 1, further comprising: a second fluid chamber within the housing and in communication with the actuator; and a second intensifier piston comprising a first end in communication with a pressure source and a second end in communication with the second fluid chamber, wherein the first end of the second intensifier piston comprises a surface area greater than that of the second end of the second intensifier piston, wherein pressure from the pressure source applies a third pressure to the second intensifier piston to move the second intensifier piston in a second direction, wherein movement of the second intensifier piston in the second direction applies a fourth pressure to fluid in the second fluid chamber, wherein the fourth pressure is greater than the third pressure, and wherein the fourth pressure applies force to the actuator to cause the actuator to urge the anchoring member toward the retracted position.

4. The apparatus of claim 3, wherein the second fluid chamber comprises a volume greater than that of the first fluid chamber.

5. The apparatus of claim 3, wherein the second direction is opposite the first direction.

6. The apparatus of claim 3, wherein the pressure source comprises a mandrel extending logintudinally through the housing, wherein the mandrel is vertically movable

relative to the second intensifier piston, and wherein contact between the first end of the second intensifier piston and the mandrel, a member attached to the mandrel, or combinations thereof applies a force to urge the second intensifier piston in the second direction.

7. The apparatus of claim 1, further comprising a mandrel extending longitudinally through the housing, wherein the mandrel comprises an upper end and a lower end engaged with the housing, and wherein the upper end of the mandrel, the housing, or combinations thereof is adapted for engagement with a string, a tool, or combinations thereof

8. The apparatus of claim 7, wherein the upper end of the mandrel comprises a diameter greater than at least one other portion of the mandrel, wherein the mandrel is

vertically movable relative to the first intensifier piston, wherein the diameter of the upper end is adapted to contact the first end of the first intensifier pistons to apply a force thereto.

9. The apparatus of claim 7, wherein the lower end of the mandrel comprises a retainer engaged therewith, wherein the retainer is removably engaged with the housing via a connector, and wherein the mandrel is vertically movable relative to the housing upon application of a force thereto sufficient to disengage the connector from the housing.

10. The apparatus of claim 9, further comprising: a second fluid chamber within the housing and in communication with the actuator; and a second intensifier piston comprising a first end proximate to the lower retainer and a second end in communication with the second fluid chamber, wherein the first end of the second intensifier piston comprises a surface area greater than that of the second end of the second intensifier piston, wherein the retainer comprises a diameter greater than that of the mandrel, and wherein contact between the retainer and the first end of the second intensifier piston applies a third pressure to the second intensifier piston to move the second intensifier piston in a second direction, wherein movement of the second intensifier piston in the second direction applies a fourth pressure to fluid in the second fluid chamber, wherein the fourth pressure is greater than the third pressure, and wherein the fourth pressure applies force to the actuator to cause the actuator to urge the anchoring member toward the retracted position.

11. The apparatus of claim 1, wherein the anchoring member, the actuator, or combinations thereof is positioned relative to the housing such that movement of the anchoring member toward the extended position extends the anchoring member at a non-parallel angle relative to a longitudinal axis of the housing.

12. The apparatus of claim 11, wherein the anchoring member, the actuator, or combinations thereof is positioned relative to the housing such that movement of the anchoring member toward the extended position extends the anchoring member generally perpendicular to the longitudinal axis of the housing .

13. An anchoring apparatus for engaging a borehole surface, the apparatus comprising:

a first fluid chamber within the housing and in communication with the actuator; a first intensifier piston comprising a first end in communication with a fluid source and a second end in communication with the first fluid chamber, wherein the first end of the first intensifier piston comprises a surface area greater than that of the second end of the first intensifier piston; a mandrel extending longitudinally through the housing, wherein the mandrel comprises an upper end proximate to the first intensifier piston and a lower end, and wherein the mandrel is vertically movable relative to the housing;

a second fluid chamber within the housing and in communication with the actuator; a second intensifier piston comprising a first end in communication with the lower end of the mandrel and a second end in communication with the second fluid chamber, wherein the first end of the second intensifier piston comprises a surface area greater than that of the second end of the second intensifier piston, wherein fluid from the fluid source applies a first pressure to the first intensifier piston to move the first intensifier piston in a first direction, wherein movement of the first intensifier piston in the first direction applies a second pressure to fluid in the first fluid chamber, wherein the second pressure is greater than the first pressure, and wherein the second pressure applies force to the actuator to cause the actuator to urge the anchoring member toward the extended position, wherein contact between the lower end of the mandrel and the second intensifier piston applies a third pressure to the second intensifier piston to move the second intensifier piston in a second direction, wherein movement of the second intensifier piston in the second direction applies a fourth pressure to fluid in the second fluid chamber, wherein the fourth pressure is greater than the third pressure, and wherein the fourth pressure applies force to the actuator to cause the actuator to urge the anchoring member toward the retracted position.

14. The apparatus of claim 13, wherein the mandrel passes through a bore in the first intensifier piston, wherein the upper end of the mandrel, a member attached to the upper end of the mandrel, or combinations thereof comprises a diameter greater than that of the bore, and wherein contact between the first end of the first intensifier piston and the upper end of the mandrel, the member attached to the upper end of the mandrel, or combinations thereof applies a force to urge the first intensifier piston in the first direction.

15. The apparatus of claim 13, wherein the second fluid chamber comprises a volume greater than that of the first fluid chamber.

16. The apparatus of claim 13, wherein the lower end of the mandrel comprises a retainer engaged therewith, wherein the retainer is removably engaged with the housing via a connector, and wherein the mandrel is vertically movable relative to the housing upon application of a force thereto sufficient to disengage the connector from the housing.

17. The apparatus of claim 16, wherein the retainer comprises a diameter greater than that of the mandrel, and wherein contact between the retainer and the first end of the second intensifier piston applies the third pressure to the second intensifier piston.

18. An anchoring apparatus for engaging a borehole surface, the apparatus comprising:

a housing; an actuator within the housing; a first fluid chamber within the housing and in communication with the actuator; and a first intensifier piston comprising a first end in communication with the first fluid chamber and a second end, wherein the second end of the first intensifier piston comprises a surface area greater than that of the first end of the first intensifier piston, wherein application of a first pressure to the second end of the first intensifier piston moves the first intensifier piston, wherein movement of the first intensifier piston applies a second pressure to fluid in the first fluid chamber, wherein the second pressure is greater than the first pressure, and wherein the second pressure is applied to the actuator.

19. The anchoring apparatus of claim 18, further

comprising : a second fluid chamber within the housing and in communication with the actuator; and a second intensifier piston comprising a first end in communication with the second fluid chamber and a second end, wherein the second end of the second intensifier piston comprises a surface area greater than that of the first end of the second intensifier piston, wherein application of a third pressure to the second end of the second intensifier piston moves the second intensifier piston, wherein movement of the second intensifier piston applies a fourth pressure to fluid in the second chamber, wherein the fourth pressure is greater than the third pressure, and wherein the fourth pressure is applied to the actuator.

20. The anchoring apparatus of claim 19, further

comprising a mandrel within the housing, wherein the mandrel is vertically movable relative to at least one of the first intensifier piston and the second intensifier piston, and wherein the mandrel is adapted to contact the first

intensifier piston to apply the first pressure thereto, to contact the second intensifier piston to apply the third pressure thereto, or combinations thereof.