Hybrid dissolvable plug with improved drillability

Abstract

A frac plug is disclosed that is used for isolating a lower portion of a wellbore from an upper portion to enable a fracking process on newly created perforations in casing or liner pipe where the frac plug is particularly designed rapid drill out after all the fracking operations have been completed. The frac plug includes arrangements for holding the polymer or rubber element from rotation as the plug is being drilled. One arrangement includes pins that lock the polymer element to the bottom cone. In another, the polymer element is simply bonded by adhesive to the faceted cone. The facets on the cone prevent the cone from rotating in the wellbore by being pressed against the flat bottom slip segments that remain locked to the casing or liner pipe.

What is claimed is: 
     
         1 . A plug deployable into a wellbore extending through a subterranean earthen formation to isolate a downhole section of the wellbore from an opposing uphole section of the wellbore, the plug comprising:
 an annular sealing element extending between a pair of longitudinally opposed ends and configured to extend radially outwards into sealing engagement with a wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration;   a slip assembly coupled to the sealing element and configured to attach to the wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration, wherein the slip assembly comprises one or more radially displaceable slip members and an extrusion ring having a radially inclined outer surface configured to drive the one or more slip members radially outwards and into engagement with the wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration, wherein the extrusion ring is rotationally locked to one of the pair of longitudinally opposed ends of the sealing element with respect to a central axis of the plug; and   one or more connectors, separate from the extrusion ring and the annular sealing element, and extending longitudinally between the annular sealing element and the extrusion ring to restrict relative rotation between the sealing element and the extrusion ring.   
     
     
         2 . The plug according to  claim 1 , wherein the plug includes components that are formed of at least one of a magnesium alloy and an aluminum alloy to dissolve in the wellbore. 
     
     
         3 . The plug according to  claim 1 , wherein the extrusion ring comprises a radially inclined outer surface contacting a radially inner surface of the one or more slip members. 
     
     
         4 . The plug according to  claim 1 , wherein the plug comprises one or more first components formed of at least one of a magnesium alloy and an aluminum alloy and one or more second components formed from a fiber reinforced material. 
     
     
         5 . The plug according to  claim 1 , wherein the one or more slip members comprises a slip belt. 
     
     
         6 . A plug deployable into a wellbore extending through a subterranean earthen formation to isolate a downhole section of the wellbore from an opposing uphole section of the wellbore, the plug comprising:
 an annular sealing element extending between a pair of longitudinally opposed ends and configured to extend radially outwards into sealing engagement with a wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration;   a slip assembly coupled to the sealing element and configured to attach to the wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration, wherein the slip assembly comprises one or more radially displaceable slip members and an extrusion ring having a radially inclined outer surface configured to drive the one or more slip members radially outwards and into engagement with the wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration, wherein the extrusion ring is rotationally locked to one of the pair of longitudinally opposed ends of the sealing element with respect to a central axis of the plug; and   a plurality of connectors circumferentially spaced around a central axis of the annular sealing element and each extending longitudinally between the annular sealing element and the extrusion ring to restrict relative rotation between the sealing element and the extrusion ring.   
     
     
         7 . The plug according to  claim 6 , wherein each of the plurality of connectors has a central axis that is radially spaced from the central axis of the annular sealing element. 
     
     
         8 . The plug according to  claim 6 , wherein each of the plurality of connectors extends longitudinally between an opposing pair of terminal ends. 
     
     
         9 . The plug according to  claim 6 , wherein the plug includes components that are formed of at least one of a magnesium alloy and an aluminum alloy to dissolve in the wellbore. 
     
     
         10 . The plug according to  claim 6 , wherein the plug comprises one or more first components formed of at least one of a magnesium alloy and an aluminum alloy and one or more second components formed from a fiber reinforced material. 
     
     
         11 . The plug according to  claim 6 , wherein the plug comprises a mandrel and a nose coupled to the mandrel and defining a downhole end of the plug, and wherein the mandrel and the nose are formed from dissolvable materials while the remainder of the plug is formed from non-dissolvable materials. 
     
     
         12 . The plug according to  claim 6 , wherein the extrusion ring is bonded to the sealing element by an adhesive. 
     
     
         13 . The plug according to  claim 6 , wherein the extrusion ring comprises a radially inclined outer surface contacting a radially inner surface of the one or more slip members. 
     
     
         14 . A plug deployable into a wellbore extending through a subterranean earthen formation to isolate a downhole section of the wellbore from an opposing uphole section of the wellbore, the plug comprising:
 an annular sealing element extending between a pair of longitudinally opposed ends and configured to extend radially outwards into sealing engagement with a wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration;   a slip assembly coupled to the sealing element and configured to attach to the wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration, wherein the slip assembly comprises one or more radially displaceable slip members and an extrusion ring having a radially inclined outer surface configured to drive the one or more slip members radially outwards and into engagement with the wall of the wellbore in response to the plug transitioning from a run-in configuration to a set configuration, wherein the extrusion ring is rotationally locked to one of the pair of longitudinally opposed ends of the sealing element with respect to a central axis of the plug; and   one or more elongate connectors having opposing terminal ends extending longitudinally between the annular sealing element and the extrusion ring to restrict relative rotation between the sealing element and the extrusion ring.   
     
     
         15 . The plug according to  claim 14 , wherein a first of the opposing terminal ends of the one or more elongate connectors is coupled to the annular sealing element and a second of the opposing terminal ends of the one or more elongate connectors is coupled to the extrusion ring. 
     
     
         16 . The plug according to  claim 14 , wherein a first of the opposing terminal ends of the one or more elongate connectors is received in the annular sealing element and a second of the opposing terminal ends of the one or more elongate connectors is received in the extrusion ring. 
     
     
         17 . The plug according to  claim 14 , wherein the one or more elongate connectors has a central axis that is radially spaced from a central axis of the annular sealing element. 
     
     
         18 . The plug according to  claim 14 , wherein the plug includes components that are formed of at least one of a magnesium alloy and an aluminum alloy to dissolve in the wellbore. 
     
     
         19 . The plug according to  claim 14 , wherein the plug comprises one or more first components formed of at least one of a magnesium alloy and an aluminum alloy and one or more second components formed from a fiber reinforced material. 
     
     
         20 . The plug according to  claim 14 , wherein the plug comprises a mandrel and a nose coupled to the mandrel and defining a downhole end of the plug, and wherein the mandrel and the nose are formed from dissolvable materials while the remainder of the plug is formed from non-dissolvable materials.