BACKGROUND
In industries concerned with actions taken within earth formations, it is often necessary to anchor tools needed for a plethora of possible operations. Anchors come in many different forms and constructions and each has its strengths and weaknesses and hence each type tends to be favored for a relatively specific class of applications. While existing anchors work well for their intended purpose and are generally reliable, the costs of operational inconsistencies in downhole applications are significant. The art is therefore consistently seeking and interested in alternative constructions that improve reliability.
SUMMARY
An anchor system includes an anchoring device and at least one of a restriction indicator and a load isolation device in operable communication with the anchoring device.
A method for setting of an anchoring system includes protecting an outer gage diameter of an anchoring device with a restriction indicator having a gage diameter greater than any gage diameter of the anchoring device; and configuring the restriction indicator to hold a selected amount of string weight in the event that the system contacts a restriction in a borehole in which the system is being run.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings wherein like elements are numbered alike in the several Figures:
FIG. 1 is a perspective view of an anchor system;
FIG. 2 is a cross section view of the anchor illustrated in FIG. 1 taken along section line 2-2;
FIG. 3 is a schematic enlarged view of the area proximate the enlarged ends 58;
FIG. 4 is a representation similar to that of FIG. 2 with the system modified to set based upon landing at a preinstalled structure in a borehole; and
FIG. 5 is a schematic illustration of a hydraulic embodiment of the system disclosed herein.
DETAILED DESCRIPTION
Referring to FIG. 1, an anchor system 10 is illustrated in perspective view. A mid to uphole portion of the drawing, identified by bracket 12, depicts an anchoring device that is commercially available from Baker Hughes Incorporated under Product Family H15054. Downhole of this portion (to the right in the Figure) is a new configuration providing significantly improved function to the H15054 product. The new configuration may include either or both of a restriction indicator 14 and a load isolation device 46, which in one embodiment is a collet device and in other embodiments may be a spring, j-slot, shear ring, parting ring, body lock ring, burst disk or other release configuration capable of selectively permitting setting of the anchor. Each has a separate function and hence can be used independently with the related benefit to an anchor system using the same. Together, additional benefit is achieved. An embodiment that includes both the restriction indicator 14 and the load isolation device 46 is specifically illustrated. It is to be understood that either of these features could be deleted from the drawing such that the drawing illustrates the other configuration alone.
Referring to FIG. 2, the restriction indicator 14 is to be configured to have a gage surface 20 that is of greater dimension than any other portion of the system 10. It is to be appreciated that the surface 20 is also axially relatively short and the restriction indicator 14 further includes a frustoconical section 22. These attributes of the restriction indicator 14 work together to ensure that the restriction indicator is the most likely component of the system 10 to experience contact at a restriction within the borehole in which the system 10 is run. The configuration also ensures that in the event that a contact occurs, it is relatively easy to dislodge the system because of the relatively narrow band of material at surface 20 that can be lodged. When the restriction indicator 14 is employed, a relatively small frictional interaction is usually all that needs to be overcome to release the system from a restriction. This is further discussed hereunder.
Restriction indicator 14 presents a relatively small gage surface 20 that is exposed to and might encounter a restriction contact. In addition, because of the short axial length of the surface 20 and the configuration of the frustocone 22, if a restriction is encountered, it is a relatively easy affair to pull the system 10 back uphole and out of the restriction. Further, the restriction indicator provides a warning signal to an operator in that the restriction indicator 14 is releasably affixed by a release member 26 to a lower cone 28 which itself is releasably affixed by a another release member 56 (shear screw(s), parting ring, body lock ring, collet, etc.) to a shear sleeve 30. In one embodiment, the release member 26 is a shear ring, but it will be understood that other release members, such as shear screw(s), parting ring, body lock ring, collet, etc., could be substituted. The release member 26 provides a signal to an operator indicative of a restriction by holding some selected amount of weight and then releasing causing a slack off in weight on the derrick (not shown) at surface and then a return of the weight, or in other words a spike (except in the negative direction with respect to load). The amplitude of the signal is dictated by the release value of the release member 26 and can be adjusted during manufacture of the system 10.
Referring now to the load isolation device 46, this feature provides the function of ensuring that the anchor system 10 sets only at a selected location such as the bottom of a borehole in which the anchor is to be used or at a landing profile (discussed hereunder as alternative embodiment) intended to cause the actuation. It ensures this by presenting a significantly lesser gage diameter than other components of the system 10. This helps in the function of the system 10 in that it predisposes the actuation of the system 10 at the selected location such as the bottom of the borehole or at a landing profile, as is intended. Because the collet is of significantly smaller gage diameter, the likelihood of being actuated by a restriction is consequently smaller. The collet 46 is releasably secured by a collet release member 48 (shear screw(s), parting ring, body lock ring, collet, etc) to the shear sleeve 30 to prevent actuations caused merely by drag of the collet 46 along borehole structures during running. It is to be appreciated that in one embodiment the collet 46 extends downhole (to the right in the drawing) of the shear sleeve 30 by enough distance to allow the collet actuation shoulder 50 to make contact with and actuate a lower cone actuation shoulder 52. Upon contact of the collet with the bottom of the hole (not shown), in the embodiment of FIGS. 1 and 2, load is built upon the collet release member 48 until a selected value of the release member is reached and surpassed. At that point the load isolation device 46 will move in an uphole direction relative to the rest of the system 10. In fact, the load isolation device 46 has simply stopped moving downhole while the rest of the system 10 continues moving downhole. The load isolation device 46 moves closer to the lower cone 28 until actuation shoulder 50 on the load isolation device 46 makes contact with the actuation shoulder 52 of the lower cone 28. In this position, the shear sleeve 30 is still extending for a lesser distance downhole than that of the load isolation device 46 thereby allowing the load isolation device 46 to provide a load to lower cone 28 and effectuate setting of the system 10.
Collet fingers 54 function to help prevent unintended actuation through the restriction indicator 14, pursuant to a restriction, by transferring from the lower cone 28 to the shear sleeve 30 the load occasioned by contact between shoulder 32 and shoulder 34, which is otherwise resisted only by setting release member 56. The fingers 54 include enlarged ends 58 to interact with the shear sleeve 30 at groove 62 and lower cone 28 through undercut 60 therein, in which the ends 58 are positioned. In this configuration, unintended actuation due to the system encountering a restriction with restriction indicator 14 requires release of the release member 26, movement of the restriction indicator 14 to load shoulders 32 and 34. At this point, however, the load being transferred between load shoulders 32 and 34 will be transmitted axially along the lower cone, and will then load into the enlarged ends 58 of the collet fingers (through load shoulder B). The enlarged ends 58 of the collet fingers will then be placed into compression against load shoulder A. While this load is applied, the setting of the anchor 10 is prevented (see FIG. 3). Thus the probability of achieving the intended setting is enhanced.
In another embodiment, illustrated in FIG. 4, a system 110 is configured to actuate based upon landing in a preinstalled structure 164. Structure 164 may be for example a tubular of some kind that has been previously placed in the borehole and is in some way held in place, perhaps by an anchoring system of some kind. The structure is configured at an uphole end thereof to interact selectively with a load isolation device 146. This removes the requirement of the previously described embodiment that the load isolation device 46 extend downhole of the shear sleeve 30. In the illustrated embodiment of FIG. 4, the shear sleeve 130 extends downhole of the load isolation device 146 and thereby offers additional protection thereto with regard to unintentionally engaging the load isolation device 146, shearing the release member 148, and setting the system 110 while running downhole. The structure 164 is configured to receive the shear sleeve 130 thereby aligning the system 110 in the borehole. After the shear sleeve 130 is received in the structure 164, actuation end 166 will come into loaded contact with collet end 168 and cause actuation of the system 110 similarly to that described above for the embodiment of FIGS. 1-3. It will be understood that in one embodiment as shown, the ends 166 and 168 are profiled complementarily to one another. This profile may be angled as shown or orthogonal, or the surface may have another shape that aids in orientation of the system 110, for example.
Referring now to FIG. 5, another alternate embodiment of the system 210 is illustrated. In this embodiment the system 210 is actuated hydraulically and requires no set down weight on bottom or any structure. This embodiment may be located anywhere in the borehole that is desired. The system 210 includes a bottom sub 270 that replaces the shear sleeve 30 and 130 of the previous embodiments. The bottom sub 270 includes a hydraulic pathway 272 therein that feeds a port 274. Hydraulic pressure is provided to this port 274 by string pressure that may be applied from the surface or other remote location. It is also possible for the system 210 to carry its own pressure source which may be in the form of a selectively openable chamber, a pump, etc. for example. Upon pressurization of the port 274, fluid pressure within a hydraulic chamber 276, defined in part by the collet 246 and in part by the sub 270, is contained therein by seals 278, which may be for example, o-rings. The increasing pressure in hydraulic chamber 276 ultimately will cause release of the release member 248 thereby facilitating movement of the collet 246 toward lower cone 28. This movement is analogous to the movement of the load isolation device 46 in the first described embodiment and causes similar consequent actions of the system 210.
While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.
Patent Application
20100230116
