GB2334540A - Inductively powered insert tool - Google Patents

Abstract

A non-intrusive insert tool 10 which employs an inductive power supply system is disclosed. Generally the tool includes a coil (not shown) which is responsive to a field generated by another coil 16 of a downhole tool 12, e.g. a safety valve, which has been preinstalled in the appropriate location and connected to a power supply 14. The insert tool is constructed to be received with the other tool to remediate that tool in the event of a failure.

Description

MON-SrVZ ZNSflT TOOL cOOTR0L Background of the Invention: Field of the Invention In the oil tools industry, power distribution and connection downhole has always been challenging to engineers and technicians.

Ristorically power has been supplied from the surface via a hard wire to each component of the well that requires power. As is appreciated, this situation can lead to many power supply cables being tripped downhole and an increase in the chances of an interruption pursuant to a cable separation.

Batteries have been of interest for some time in that they can be installed on or near the tool requiring power. Unfortunately, battery technology has not progressed sufficiently to provide a reliable power source in the downhole environment.

Alternatively, power has been provided to downhole tools inductively using a casing mounted hard wired coil on a non-magnetic casing interval and a second coil associated with the tool to be powered. Upon aligning the coils and energizing the first coil, the field generated thereby generates a current in the second coil mounted to the tool. Thus power to the tool is supplied. This type of system avoids the need for wet connector technology which requires proper orientation of connectors and significant safeguards against mechanical and chemical degradation or fouling of the connectors.

U.S. 4,852,648 to Akkerman et al discloses a well installation having an electrically responsive device installed therein and wherein power is supplied to the device by the inductive coupling of concentric coils. One coil is on the inside diameter of a pressure containing tube and the other is on the outside of the pressure containing tube. The teaching allows connection of power to tools.

Generally, when these tools fail they must be removed from the well and replaced. Such a procedure is time consuming and expensive and an alternate method for resolving a failed tool is required while avoiding wet connection for power to the new tool.

Summary of the Invention: The above-discussed and other drawbacks and deficiencies of the prior art are overcome or alleviated by the insert tool of the invention. More specifically, the insert tool of the invention is a remedial tool for a malfunctioning subsurface safety valve. Upon initial installation of the original safety valve it will have been fitted with a coil having an umbilical electrical cord to the surface or other power supply source. Normally the coil would not be energized if the original valve was working properly. In the event of a valve failure however, the extremely arduous task of removing the entire string to replace the valve is avoided by running the remedial insert tool of the invention. The insert tool will be powered inductively by the coil in the original valve which has until this point been dormant. By employing the remedial tool which itself is preferably a safety valve, production can continue from the well without the long shut down time required for prior art remediation of a safety valve.

The insert tool may use the powerS available from the safety valve coil in a number of ways. First, the energized coil field may be picked up by a complimentary coil in the insert tool and translated into current for use by the insert tool; second, the insert tool may become a solenoid piston by reacting to the field generated by the safety valve coil; and third, the safety valve coil may become a stator in an annular motor and the insert tool would possess the rotor. Each of these embodiments allow the insert tool to take a selected action.

The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.

Brief Description of the Drawings: Referring now to the drawings wherein like elements are numbered alike in the several FIGURES: FIGURES 1-4 are together an elongated section view of an electromechanically actuated first embodiment of the remedial insert valve of the invention with the valve closed; FIGURES 5-8 are together the view of FIGURES 1-4 but with the valve open; FIGURES 9-11 are together an elongated section view of a magnetically actuated second embodiment of the remedial insert valve of the invention with the valve closed.

FIGURES 12-14 are the view of FIGURES 9-11 with the valve open.

Detailed DescriPtion of the Preferred Embodiments: Referring to FIGURES 1-4 and principally to FIGURE 1 first, and followed seriatim by FIGURES 2, 3 and 4, an insert tool 10 of the invention is illustrated in position within the body 12 of a subsurface safety valve (shown only in part). The body 12 includes in relevant part a power line 14, which preferably is TEC wire, connected to coil 16. Coil 16 is provided in the original downhole tool which was installed in the production string. As discussed and illustrated herein, the tool is a safety valve but it should be noted that it is possible to employ the remedial insert of the invention for other downhole tools in the event of failure thereof.

During the normal life of the original safety valve the coil 16 is not energized and plays no part in the function of the original safety valve. Rather coil 16 is provided originally only so that it will be available if needed due to a failure of the original valve.

The need to employ coil 16 occurs when and if the original safety valve (whose body 12 is shown) fails to operate properly. Since it is clearly dangerous to operate a well without a safety valve due to possible blow-outs, the speedy replacement of a malfunctioning valve is paramount. When the need arises for a remedial safety valve, insert tool 10 is run downhole into the original safety valve (see 12) and locked in place as discussed hereunder. The insert tool 10 is placed so as to communicate with coil 16 which will now be energized through wire 14, usually from the surface. Upon interfacing with coil 16, insert tool 10 becomes powered and is a fully functional tool; in this case a safety valve. The safety valve aspect of the tool is a virtual replica of a full-size safety valve including a flow tube 60, a power spring 70 and a flapper 80. In this embodiment of the invention which provides electromechanical actuation of the insert tool safety valve with power supplied inductively, the actuation within the insert tool may be by any of the constructions and modes of operation of the electrically activated surface activated subsurface safety valve described in copending application serial number 08/987,686 filed December 9, 1997 which is assigned to the assignee hereof and entirely incorporated herein by reference.

The insert tool 10 includes a set of dogs 20 which are at rest within the outside diameter of the tool 10 during run in and are displaceable radially outwardly when tool 10 is properly located within the original safety valve to secure the insert tool in the selected position. Dogs 20 number preferably four (varies with engineering parameters, diameter and pressure expectancy) around the circumference of tool 10 for stability and reliability. XThe activation of dogs 20 is by lock sleeve 22 which during run in is in the position shown in FIGURE 1 and after activation is in the position shown in FIGURE 5. Upon landing tool 10 in landing profile 23, additional set down weight causes lock sleeve 22 to slide further downhole relative to power sub 30. The narrowed nose 24 allows ramp 26 to be created. Ramp 26 is the structure that urges dogs 20 radially outwardly into position groove 28 of body 12. The position groove distance from the coil is known so the insert is manufactured to place the complimentary coil in communication with the coil 16 when the dogs 20 are locked into position groove 28.

Power sub 30 includes lock groove 32 which allows snap ring 34 to move thereinto when dogs 20 are in position groove 28. The snap ring prevents lock sleeve 22 from moving uphole and therefore prevents dogs 20 from becoming dislodged. The tool 10 is preferably permanently located in the selected position. It will be understood however, that other locking arrangements familiar to the art could be employed which allow for a non-permanent locking of the insert tool in the original safety valve. For assembly purposes, collar 36 is threadedly connected to power sub 30 and stop ring 38 is provided radially inwardly of collar 36 to prevent over threading.

Referring to FIGURE 2, power sub 30 slidingly engages flow tube 60. Flow tube 60 is in contact with components of the tool at some locations but does include annular space 40 for sand control. Power sub 30 also provides a relatively large annular space 42 therein to accommodate tool coil 44 and ring gear 46 as well as a means for operating the valve. In the drawing this is motor 48. The coil 44 is subject to a field generated by coil 16 being powered from a remote location which commonly is a surface location, coil 44 then creates an electric current and supplies it to the actuating components of the insert tool 10. In this manner no direct electrical connectors are required and the drawbacks inherent therein are avoided. At the downhole end 50 of the annular space 42 is a bushing 52 which supports a shaft 54 of motor 48. Ring 86 also supports shaft 54 as well as solenoids 58 located in either side of power sub 30. Solenoids 58 function to activate ramp 62 to push yoke half 64 into contact with lead screw 66. The operation of these parts as well as other configurations to activate the flapper 80 is more fully described in copending U.S. application serial number 08/987,686 filed December 9, 1997 previously incorporated herein by reference and is not material to the present invention. Rather the non-intrusive remedial insert tool and the means of powering the insert tool is the invention. Upon powering the solenoids 58 and motor drive system, flow tube 60 is biased downhole and opens a flapper 80 in the insert tool 10. By the invention, the function of the failed downhole tool is easily and reliably replaced.

In a second embodiment of the invention the coil created current is replaced by a magnetic activation system. This system, in some ways, is more simple than the first in that no electric actuation mechanism is required in the insert tool 110. In this embodiment the insert tool 110 merely provides a solenoid like internal component which itself is the actuator. More specifically, and referring to FIGURES 9-11 and 12-14 (alternate position illustrations), body 112 of the nonfunctioning originally installed tool (in the drawings and explanation hereof, a safety valve) provides as originally installed a power cable 114 which is attached to a power source preferably at the surface and which cable remains dormant for the functional life of the originally installed downhole tool. The cable 114 is connected to a coil 116 which also is dormant during the functional life of the originally installed downhole tool. In this embodiment coil 116 is employed, when necessary due to failure of the originally installed tool to create a magnetic field which is used by the insert tool 110 to cause it to move in a solenoid like manner. As will be appreciated by one of skill in the art, this embodiment is useful when the stroke necessary for operation of the downhole tool that has malfunctioned is not of a substantial length. The reason for this, of course, is that solenoids do not create a great distance of stroke with sufficient force and in this embodiment the solenoid stroke length is the entire actuating force. When longer actuation strokes are required, other embodiments of this invention are indicated.

Upon malfunction of the originally installed tool, of which body 112 is a part, tool 110 is run in the hole. Tool 110 lands in landing area 116 and is supported there by projection 118. In this embodiment, the insert tool itself (FIGURE 9) includes top sub 120 which is threadedly connected to mid sub 122. Mid sub 122 is located during assembly by collar 124 and is threadedly connected at its downhole end to flapper sleeve 126. Flapper sleeve 126 extends downhole to lower sub 128 and is threadedly connected thereto.

Flapper sleeve 126 is also pinned to lower sub 128 by pins 130. Lower sub 128 is also threadedly connected and pinned by pins (132) to flapper sub 134. Flapper sub 134 supports flapper 136 which, includes conventional components (not labeled).

Lower sub 128 is bordered as its uphole end by spring collar 138 which supports spring block 140. Power spring 142 is located adjacent block 140 and functions conventionally. Power spring 142 is blocked at its upper end by upper spring block 144. Adjacent upper spring block 144 is disposed centering ring 146 which is preferably of a pentagonal shape placing the pointed surface outwardly such that the point 148 contacts flapper sleeve 126 and centers flowtube 150 in the tool. Flow tube 150 is threadedly connected to magnet sleeve 152 so as to be moveable thereby.

Upon energization of Coil 115, magnet sleeve 152 is urged downhole. Flow tube 150 moves downhole with magnet sleeve 152 and forces flapper 136 open in a conventional way. The downhole movement described compresses power spring 142. Thus in the event of a power failure or an intended valve closure, the power spring moves flow tube 150 uphole and the flapper 136 closes.

In this embodiment, relatively small valves are indicated due to the limited throw that is possible in a solenoid arrangement.

While preferred embodiments have been shown and described, various 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 illustration and not limitation.

Claims (6)

1. What is claimed is: CLAIM 1. A downhole tool remedial insert system comprising: a) a preinstalled downhole tool having a first coil located therein, said first coil being connected to a power supply; b) an insert tool having a second coil located therein, said second coil being positionable so as to operatively communicate with said first coil, said insert carrying out a at least one function of said preinstalled downhole tool.
2. CLAIM 2. A remedial insert for a preinstalled downhole tool having a first coil therein connected to a power source comprising: a) an insert tool body; b) a second coil in said body, said second coil being located so that when said second coil is in operative communication with said first coil, said body being positioned to perform at least one function of said preinstalled downhole tool.
3. CLAIM 3. A method for replacing at least one function of a downhole tool having a first coil therein comprising: a) installing a remedial insert tool having a second coil therein so as to align said second coil with said first coil; b) powering said first coil to create a field said field inductively creating a current in said second coil to thereby provide power to said insert tool.
4. CLAIM 4. A downhole tool remedial insert system comprising: a) a preinstalled downhole tool having a coil located therein, said first coil being connected to a power supply; b) an insert tool having a permanent magnet therein, said magnet being positionable so as to be in operative communication with said coil, whereby said insert tool carries out at least one function of said preinstalled downhole tool.
5. CLAIM 5. A remedial insert for a preinstalled downhole tool having a coil therein connected to a power source comprising: a) an insert tool body; b) a magnet in said body, said magnet being located so that when said magnet is in operative communication with said coil, said body being positioned to perform at least one function of said preinstalled downhole tool.
6. CLAIM 6. An insert tool comprising: a) a tool outer housing; b) a tool inner housing moveably axially in said outer housing;

   c) a magnet mounted in said inner housing, said magnet being responsive to a field generated externally to said insert tool.