Split ring slips , slotted unibody slips, multi-segment interlocking slips and methods of making the same

Abstract

Multiple inventions for slips for use in settable downhole tools, for use in oil and gas wells are disclosed. Slips help lock the settable tool to an adjacent casing. In some embodiments, injection moldable interlocking slip segments are provided for use in a multi-segmented dissolvable slip in a downhole tool. In some embodiments, a slip with a single full split is provided that, during setting, expands at the split rather than breaking apart.

1 . A slip for use about a mandrel of a settable downhole tool, the slip configured to hold the tool within a casing when the slip is in a set position, the slip comprising:
 multiple circumferential segments, each segment having a first side wall and a second side wall, an inner wall and an outer wall, and an upper wall and a lower wall, the multiple circumferential segments configured to be placed adjacent each other;   multiple gripping structures;   cooperating interlocking couple comprising a projecting member on a side wall of a segment of the multiple circumferential segments and a receiving cavity on another side wall to an adjacent segment;
 wherein the side walls are configured and the segments arranged, so the multiple coupled segments engage flush with adjacent segments to form a ring-shaped slip body; and 
 wherein at least some of the outer walls of at least some of the multiple circumferential segments are configured to receive a least some of the multiple gripping structures such that at least some portion of the gripping structure contacts the outer wall of the circumferential segment and at least another portion of the gripping structure stands above the outer wall of the circumferential segment. 
   
     
     
         2 . The slip of  claim 1 , wherein the projecting member is a dovetail and the receiving cavity comprises walls configured to snugly receive the projecting member. 
     
     
         3 . The slip of  claim 1 , wherein the circumferential segments comprise a material that is degradable in a downhole fluid. 
     
     
         4 . The slip of  claim 3 , wherein the degradable material is a polymer acid. 
     
     
         5 . The slip of  claim 1 , wherein the multiple gripping members include multiple buttons. 
     
     
         6 . The slip of  claim 1 , wherein the multiple gripping members include a button assembly. 
     
     
         7 . The slip of  claim 1 , wherein the multiple gripping members include a wicker. 
     
     
         8 . The slip of  claim 1 , wherein the cooperating interlocking couple is configured to break apart when a radially expansive force exceeds a minimum force, wherein the minimum force is achieved during setting of the tool. 
     
     
         9 . The slip of  claim 1 , wherein the cooperating interlocking couple is configured to bend and come apart when a radially expansive force exceeds a minimum force, wherein the minimum force is achieved during setting of the tool. 
     
     
         10 . The slip of  claim 8 , wherein the minimum force is at least 100 psi. 
     
     
         11 . The slip of  claim 1 , wherein the multiple circumferential segments are identical. 
     
     
         12 . The slip of  claim 1 , further including an adhesive between adjacent side walls. 
     
     
         13 . The slip of  claim 1 , wherein the multiple circumferential segments are comprised of an injection undegradeable material. 
     
     
         14 . The slip of  claim 1 , wherein the multiple circumferential segments are identical; and wherein the multiple circumferential segments are comprised of an injection undegradeable material. 
     
     
         15 . The slip of  claim 1 , wherein the multiple gripping structures are wickers; and wherein the outer walls of the multiple segments are configured to receive the wicker pads. 
     
     
         16 . The slip of  claim 15 , wherein the outer walls are configured for an interference fit. 
     
     
         17 . The slip of  claim 1 , wherein at least some of the multiple gripping structures are injection molded with a circumferential segment. 
     
     
         18 . A gripping device for use about a mandrel of a settable downhole tool, the gripping device configured to engage a casing when the tool is in a set position, the gripping device comprising:
 a first split ring slip, the first split ring slip comprising a body having an outer surface and an inner surface, the inner surface having at least a first tapering wall section, and a first perimeter and a second perimeter, the outer surface comprising multiple recesses, the first split ring slip having a split extending through the body from the outer surface to the inner surface and from the first perimeter to the second perimeter, the first split ring slip further comprising multiple buttons configured for receipt into the recesses such that part of the button stands above the outer surface and part of the button is engaging a wall of the recess;
 wherein, during setting, a width of the split expands. 
   
     
     
         19 . The gripping device of  claim 18 , wherein the split is straight and parallel to the long axis of the tool. 
     
     
         20 . The gripping device of  claim 18 , wherein the split is straight, but at a non-normal angle with respect to a long axis of the tool. 
     
     
         21 . The gripping device of  claim 18 , wherein the split includes a first section that is straight and parallel to a long axis of the tool, a second section that is straight and perpendicular to the long axis of the tool, and a third section that is straight and parallel to the long axis of the tool but spaced apart from the first section. 
     
     
         22 . The gripping device of  claim 18 , wherein the split is a full split. 
     
     
         23 . The gripping device of  claim 18 , further including neck connectors. 
     
     
         24 . A split ring assembly for use about a mandrel of a settable downhole tool configured to engage a casing when the tool is in a set position, the split ring assembly comprising:
 a first split ring slip, the first split ring slip comprising a body having an outer surface and an inner surface, the inner surface having at least a first tapering wall section, and a first perimeter and a second perimeter, the outer surface comprising multiple recesses, the first split ring slip having a split extending through the body from the outer surface to the inner surface and from the first perimeter to the second perimeter, the first split ring slip further comprising multiple buttons configured for receipt into the recesses so part of at least some of the buttons project outside of the outer surface and part of at least some of the buttons engage a wall of a recess; and   a second split ring slip, the second split ring slip comprising a body having an outer surface and an inner surface, the inner surface having at least a first tapering wall section, and a first perimeter and a second perimeter, the outer surface comprising multiple recesses, the second split ring slip having a split extending through the body from the outer surface to the inner surface and from the first perimeter to the second perimeter, the second split ring slip further comprising multiple buttons configured for receipt into the recesses such that part of the button stands above the outer surface and part of the button is engaging a wall of the recess;
 wherein the first and second split ring slips are mechanically coupled together so expansion of one of the first or second split radially outward movement during setting may cause the other to expand. 
   
     
     
         25 . The split ring assembly of  claim 24 , wherein the mechanical couple is a tongue in groove. 
     
     
         26 . The split ring assembly of  claim 24 , wherein the splits are full splits. 
     
     
         27 . A settable downhole tool for use in a casing comprising:
 a mandrel;   a sealing element;   a slip;   a structural element that lays adjacent to the slip when the tool is in an assembled and pre-set condition;
 wherein the structural element and slip are integral as a result of a connector neck between them, in a pre-set and run in condition. 
   
     
     
         28 . The settable downhole tool of  claim 27 , wherein the connector neck is configured to break when the tool sets in the casing. 
     
     
         29 . The settable downhole tool of  claim 27 , wherein the structural element, slip and connector neck are comprised of an injection moldable material. 
     
     
         30 . The settable downhole tool of  claim 27 , wherein the structural element, slip and connector neck are injection molded from a composition that is degradable in a downhole fluid. 
     
     
         31 . The settable downhole tool of  claim 27 , wherein the structural element, slip and connector are injection molded. 
     
     
         32 . A slip for use about a mandrel of a settable downhole tool, the slip configured to hold the tool within a casing when the slip is in a set position, the slip comprising:
 multiple circumferential segments, each segment having a first side wall and a second side wall, an inner wall and an outer wall, and an upper wall and a lower wall, the multiple circumferential segments configured to be placed adjacent each other;   at least one band for holding the multiple segments into a ring such that adjacent side walls are flush to one another.   
     
     
         33 . The slip of  claim 32 , further including a bonding agent for bonding adjacent side walls. 
     
     
         34 . A slip assembly for use in a downhole settable tool, the slip assembly comprised of segments configured to hold the tool within a casing when the tool is set within the casing, the assembly comprising:
 a ring comprising multiple segments;   each segment having a receiving circumferential side and an opposite projecting circumferential side;   each receiving side has an inward slot for circumferentially holding a projection from an adjacent segment's projecting side;   
       each projecting side has an outward projection for being circumferentially held within the slot of an adjacent segment's receiving side; 
       each segment's receiving side is coupled with the projecting side of the adjacent segment by the projecting side's projection being circumferentially held within the receiving side's slot;
 the multiple coupled segments comprise a ring of circumferentially coupled segments configured to be located about the tool's mandrel; and 
 
       the ring is circumferentially and radially expandable responsive to outward radial force on the inner radial side of the ring when the tool is set within the casing, wherein at least some of the circumferential expansion will occur by at least some of the projection within slot couplings decoupling, and the decoupled segments circumferentially expanding relative to each other and radially expanding toward the casing. 
     
     
         35 . The assembly of  claim 34 , wherein each slot extends only part way through the segment from one side or face of the segment and does not open to an opposing side or face of the segment. 
     
     
         36 . The assembly of  claim 34 , wherein the slot of a first segment is an axial slot which opens to a first axial face of the first segment; and the projection of an adjacent second segment is a axial projection which is slidably axially positioned into the first segment's slot through the slot's opening to the first segment's first axial face. 
     
     
         37 . The assembly of  claim 36 , wherein
 the slot has a first axial end opening to the first axial face and a second axial end opening to a second opposing axial face, the slot is a continuous slot from the first axial end to the second axial end, and the first axial end of the slot is wider than the second axial end of the slot;   the projection of the adjacent second segment has a first axial end and a second axial end and the first end of the projection is narrower than the second end of the projection, the first end of the projection is narrower than the first end of the slot and the projection is configured to be capable of slidably fitting into the slot through the slot's first end, and   the second end of the projection is wider than the first end of the slot and holds the projection within the slot against the projection sliding entirely outside of the slot through the slot's first end.   
     
     
         38 . The assembly of  claim 34 , wherein:
 at least some of the segments are injection molded segments and are identical to at least some of the other segments;   the segments are configured so each segment can be coupled with each of the other segments in any segment order to comprise the ring of segments; and   each segment's projection is configured to slide into each circumferentially adjacent segment's slot, each segment's projection is configured to be circumferentially held within each adjacent segment's slot, and the multiple circumferentially coupled segments comprise the ring of multiple segments.   
     
     
         39 . The assembly of  claim 34 , wherein:
 the slot of a first segment is a radial slot which opens to an inner radial face of the first segment; and   the projection of an adjacent second segment is a radial projection which is slidably radially positioned into the first segment's slot through the slot's opening to the first segment's inner radial face.   
     
     
         40 . The assembly of  claim 39 , wherein:
 the slot has an inner radial end opening to the inner radial face and an outer radial end opening to a second opposing radial face, the slot is a continuous slot from the inner radial end to the outer radial end, and the inner radial end of the slot is wider than the outer radial end of the slot;   the projection of the adjacent second segment has an inner radial end and an outer radial end, and the outer end of the projection is narrower than the inner end of the projection, the outer end of the projection is narrower than the inner end of the slot, and the projection is configured to be capable of slidably fitting into the slot through the slot's inner end, and   the inner end of the projection is wider than the outer end of the slot and holds the projection within the slot against the projection sliding entirely outside of the slot through the slot's outer end.   
     
     
         41 . The assembly of claim  347 , wherein a multiplicity of the segments are identical to each other. 
     
     
         42 . The assembly of  claim 27 , wherein:
 all of the assembly's segments' slots are shaped and angled similarly, all of the segments projections are shaped and angled similarly, and all of the assembly' segments' slots and projections are angled similarly, the similarity of shapes and angles being similar enough so all of the assembly's segments may be interchangeably coupled to form a ring about the downhole tool's mandrel, each segment having a projection circumferentially held within an adjacent segment's slot, the multiple circumferentially coupled segments forming a circular ring of segments for use about the mandrel.   
     
     
         43 . The assembly of  claim 42 , wherein all of the segments are identical to each other. 
     
     
         44 . The tool of  claim 34 , wherein the segments will degrade quickly enough in natural aqueous downhole fluid in the well having a pH less than 7 so within less than five days after the tool is immersed in the well's wellbore fluid, the segments dissolve enough without milling out the tool, retrieval of the tool from the well or other intervention on the tool from the surface, so the tool ceases to isolate a zone above the tool from a zone below the tool, and the degraded segments do not prevent beginning production of hydrocarbons from below where the tool was set in the casing. 
     
     
         45 . The assembly of  claim 34 , wherein each segment comprises:
 a body having an outer radial face and an inner radial face, a first axial side and a second axial side;   a wicker slot located in the outer radial face and the first axial slide side, the first axial side portion of the slot opening to the inner radial face and the outer radial face, and the outer radial face portion of the slot opening to the first axial side and the outer radial face;   
       the outer radial portion of the slot narrows as it extends from the first axial side toward the second axial side;
 a wicker insert comprised of a wicker material which is harder than a body material comprising the body, the outer face of the wicker having teeth for gripping the casing, the wicker configured to be closely held within the wicker slot; 
 the wicker is closely held within the wicker slot, the wickers teeth configured so upon setting the tool in the casing, the wicker's teeth will grip the casing and provide greater resistance against axial movement of the tool in the direction of the first axial side than resistance against axial movement of the tool in the direction away from the first axial side; 
 an upper face of the body at the first axial side portion of the slot holds the wicker within the body against movement of the wicker in the direction of the second axial side; and 
 
       the narrowing outer radial face portion of the slot holds the wicker against movement of the wicker in the direction of the second axial side. 
     
     
         46 . A slip assembly for use in a downhole settable tool, the slip assembly comprised of segments configured to hold the tool within a casing when the tool is set within the casing, the assembly comprising:
 a ring comprising multiple segments;   each segment having a receiving circumferential side and an opposite projecting circumferential side;   each receiving side has an inward slot for circumferentially holding a projection from an adjacent segment's projecting side;   each projecting side has an outward projection for being circumferentially held within the slot of an adjacent segment's receiving side;   each segment's receiving side is coupled with the projecting side of the adjacent segment by the projecting side's projection being circumferentially held within the receiving side's slot;   all of the assembly's segments' slots are shaped and angled similarly, all of the segments projections are shaped and angled similarly, and all of the assembly' segments' slots and projections are angled similarly, the similarity of shapes and angles being similar enough so all of the assembly's segments may be interchangeably coupled to form a ring about the downhole tool's mandrel, each segment having a projection circumferentially held within an adjacent segment's slot, the multiple circumferentially coupled segments forming a circular ring of segments for use about the mandrel;   at least some of the segments are injection molded segments and are identical to at least some of the other segments;   the segments are configured so each segment can be coupled with each of the other segments in any segment order to comprise the ring of segments; and   each segment's projection is configured to slide into each circumferentially adjacent segment's slot, each segment's projection is configured to be circumferentially held within each adjacent segment's slot, and the multiple circumferentially coupled segments comprise the ring of segments;   the multiple coupled segments comprise a ring of circumferentially coupled segments configured to be located about the tool's mandrel;   the ring is circumferentially and radially expandable responsive to outward radial force on the inner radial side of the ring when the tool is set within the casing, wherein at least some of the circumferential expansion will occur by at least some of the projection within slot couplings decoupling, and the decoupled segments circumferentially expanding relative to each other and radially expanding toward the casing; and   the segments will degrade quickly enough in natural aqueous downhole fluid in the well having a pH less than 7 so within less than five days after the tool is immersed in the well's wellbore fluid, the segments dissolve enough without milling out the tool, retrieval of the tool from the well or other intervention on the tool from the surface, so the tool ceases to isolate a zone above the tool from a zone below the tool, and the degraded segments do not prevent beginning production of hydrocarbons from below where the tool was set in the casing.