Abstract:
A method of setting and maintaining a tool in a set position for a period of time includes the following. Causing a component of a device to move relative to another component of the device, interengaging one or more features of at least one of the components with the another component, creating a set condition of a tool engaged with the component and the another component with the causing and interengaging. The method further includes dissolving at least the one or more features when removal of the tool is desired.

Description:
BACKGROUND 
       [0001]    Devices have been available for some time for setting a tool within a tubular such as in the downhole hydrocarbon and carbon sequestration industries. Likewise, there are devices for maintaining a tool in the set position. Though these devices work well for the purpose for which they were designed, the process for disengaging set tools and the devices that maintain the tools in the set position once the tools are no longer needed can be costly in both time and money. Disengagement of such devices from the respective tools can in some cases require running a shifting tool or a cutting tool to the device before it can be disengaged. In some cases, this might require an additional dedicated run in the hole with attendant delays and monetary costs. Those who practice in the art will therefore be receptive to methods that overcome the foregoing drawbacks. 
       BRIEF DESCRIPTION 
       [0002]    Disclosed herein is a method of setting and maintaining a tool in a set position for a period of time. The method includes causing a component of a device to move relative to another component of the device, interengaging one or more features of at least one of the components with the another component, creating a set condition of a tool engaged with the component and the another component with the causing and interengaging, and when removal of the tool is desired, dissolving at least the one or more features. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike: 
           [0004]      FIG. 1  depicts a cross sectional view of a portion of a setting device disclosed herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0005]    A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures. 
         [0006]    Referring to  FIG. 1  a portion of one embodiment of a setting device is illustrated at  10 . The portion of the setting device  10  includes at least a first component illustrated herein as a mandrel  14 , a second component illustrated herein as a housing  18  and a third component illustrated herein as a body lock ring  22 . All three of the components  14 ,  18  and  22  include features  24 ,  30 ,  34  and  38  that are interengagable with one another to allow relative movement of at least the mandrel  14  relative to the housing  18  in a first direction while preventing movement in an opposing direction. In this embodiments the features  24 ,  30 ,  34  and  38  are teeth. Specifically, the body lock ring  22  has the teeth  24  that face radially outwardly and engage with the teeth  30  that face radially inwardly on the housing  18 . The body lock ring  22  also has the teeth  34  that face radially inwardly and engage with the teeth  38  that face radially outwardly on the mandrel  14 . The optional body lock ring  22  is C shaped due to a longitudinal opening (not visible in the Figure) that extends longitudinally through the body lock ring  22 . This allows the body lock ring  22  to flex which action changes a radial size of the body lock ring  22  to thereby allow the teeth  34  thereon to ratchet relative to the teeth  38  when the mandrel  14  is pushed longitudinally toward the housing  18 . This ratcheting engagement, while allowing longitudinal movement of the mandrel  14  towards the housing  18  prevents movement of the mandrel  14  in a longitudinal direction away from the housing  18  thereby discouraging unsetting of the device  10 . 
         [0007]    In an embodiment, one or more portions of the mandrel  14 , the housing  18  and the body lock ring  22  are configured to dissolve in a set time period after being exposed to a target natural or created environment. The dissolution causes the teeth  24  of the body lock ring  22  to become disengaged with teeth  30  of the housing  18  or the teeth  34  of the body lock ring  22  to become disengaged with teeth  38  of the mandrel  22 , or both. In one embodiment, the whole of the teeth  24 ,  30 ,  34 ,  38  are configured to dissolve while in other embodiments only portions of the mandrel  14 , the housing  18  and the body lock ring  22  are configured to dissolve. More specifically, in an embodiment only one or more sets of the teeth  24 ,  30 ,  34 ,  38  may be configured to dissolve. Proportionally to the volume of dissolvable components, the ease of removal of the tool  42  will increase. Once the teeth  24 ,  30 ,  34 ,  38  are disengaged, the mandrel  14  and the housing  18  can move longitudinally away from one another allowing them to separate. This of course removes longitudinal compression of a tool  42 , such as a packer illustrated in the Figure, consequently releasing the packer. 
         [0008]    The foregoing device  10  allows an operator to set the tool  42  by longitudinally compressing the tool  42  between the mandrel  14  and the housing  18  and to maintain the tool  42  in the set position for a set period of time. The period of time may be established by the time required before dissolution of at least one of the mandrel  14 , the housing  18  and the body lock ring  22  sufficiently to disengage the teeth  24  or  34  from the teeth  30  or  38 . 
         [0009]    The mandrel  14 , the housing  18  and the body lock ring  22  can be constructed of metals and metal alloys that are configured to dissolve upon exposure to certain environments including specific fluids, temperatures and pressures, for example. The fluids can include fluids anticipated to be encountered in a downhole environment such as, oil, water, brine and combinations of the foregoing or fluids that are applied to the environment having at least a purpose of dissolving the components. As such, for applications wherein the setting device  10  is employed in an earth formation borehole  44  such as during a hydrocarbon recovery or carbon dioxide sequestration operation, for example, the dissolution of the metals can be initiated by entry into the borehole  44 . Alternately, dissolution can be initiated after exposing the setting device  10  to a selected fluid that is pumped to the location of the setting device  10 . Fluids such as acids and bases that may not occur naturally in the borehole  44  can allow additional control over timing of dissolution since the dissolution would not begin until the selected fluid is introduced to the location of the setting device  10 . 
         [0010]    In such borehole  44  applications, among other things the tool  42  may include seals  46 , slips  50  and cones  54  to allow the setting device  10  to establish and maintain sealing and anchoring of the tool  42  to a casing  58 , liner, or other structure within the borehole  44 , for example. In applications wherein the tool  42  is a fracing plug a seat  62  can be included on the housing  18  (or the mandrel  14 ) for seating of a plug (not shown) such as a ball to allow pressure to build thereagainst to perform a treating operation such as a fracing or a formation chemical treating operation. 
         [0011]    The material and/or the geometry of the mandrel  14 , housing  18  and the body lock ring  22  as well as the fluid to cause dissolution thereof can be selected to control a rate of dissolution. In so doing, the setting device  10  can be configured to maintain the tool  42  in the set configuration until after any operations that require the tool  42  be set are completed. 
         [0012]    While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.