Frac-ball with structurally weakened region

Abstract

A frac-ball for use with a well casing segmentation device and a method of controlling fluid flow through a well casing segmentation device are provided. The frac-ball includes a body having a shell configuration defined by one or more walls, with each wall having an exterior surface and an interior surface. The interior surfaces define an enclosed interior cavity. One or more structurally weakened regions are disposed in the one or more walls.

What is claimed is: 
     
         1 . A frac-ball for use with a well casing segmentation device, the frac-ball comprising:
 a body having a shell configuration defined by one or more walls, with each wall having an exterior surface and an interior surface;   wherein the interior surfaces define an enclosed interior cavity; and   one or more structurally weakened regions disposed in the one or more walls.   
     
     
         2 . The frac-ball of  claim 1 , wherein the one or more structurally weakened regions have at least one physical characteristic different from a portion of the wall surrounding the structurally weakened region. 
     
     
         3 . The frac-ball of  claim 2 , wherein the one or more structurally weakened regions each possess mechanical strength properties adequate to avoid failure within a range of predetermined well environment operating parameters and/or for a predetermined period of time in a well casing environment. 
     
     
         4 . The frac-ball of  claim 1 , wherein the one or more walls each have a thickness extending between the exterior surface and the interior surface, and at least one of the structurally weakened regions is a pocket disposed in the wall, which pocket results in a decreased wall thickness. 
     
     
         5 . The frac-ball of  claim 4 , wherein the pocket is disposed in the interior surface of the wall, or in the exterior surface of the wall. 
     
     
         6 . The frac-ball of  claim 4 , wherein a plurality of the structurally weakened regions are pockets, at least one of which pockets is disposed in the interior surface of the wall and at least one of which pockets is disposed in the exterior surface of the wall. 
     
     
         7 . The frac-ball of  claim 1 , further comprising an energetic material and a trigger mechanism, the trigger mechanism configured to selectively initiate the energetic material. 
     
     
         8 . The frac-ball of  claim 7 , wherein the energetic material and trigger mechanism are disposed within the interior cavity of the frac-ball. 
     
     
         9 . The frac-ball of  claim 8 , wherein the energetic material and trigger mechanism are configured to produce an elevated pressure event adequate to cause the structurally weakened regions to fail. 
     
     
         10 . The frac-ball of  claim 9 , wherein the energetic material and trigger mechanism are configured to produce an elevated pressure event within the interior cavity adequate to cause the structurally weakened regions to fail in a manner that causes the frac-ball to rupture into discrete pieces. 
     
     
         11 . The frac-ball of  claim 9 , wherein the energetic material and trigger mechanism are configured to produce an elevated pressure event within the interior cavity adequate to cause the structurally weakened regions to fail in a manner that produces fluid passages through the frac-ball. 
     
     
         12 . The frac-ball of  claim 9 , wherein the one or more structurally weakened regions disposed in the one or more walls each include a plug disposed within an aperture disposed within the one or more walls; and
 wherein the energetic material and trigger mechanism are configured to produce an elevated pressure event within the interior cavity adequate to cause each plug to dislodge from the one or more walls.   
     
     
         13 . The frac-ball of  claim 1 , wherein the frac-ball body is comprised of a first material that erodes, corrodes, or dissolves at a first rate when contacted with a well casing fluid, and a plug comprised of a second material that erodes, corrodes, or dissolves at a second rate when contacted with a well casing fluid is disposed in each structurally weakened region, and the second rate is greater than the first rate. 
     
     
         14 . A method of controlling fluid flow through a well casing segmentation device, comprising:
 disposing an impermeable frac-ball in a seat of a well casing segmentation device to close a fluid passage of the well casing segmentation device, wherein the frac-ball includes at least one structurally weakened region; and   causing an elevated pressure event adequate to cause the at least one structurally weakened region to fail, thereby opening the fluid passage of the well casing segmentation device.   
     
     
         15 . The method of  claim 14 , wherein the frac-ball includes an interior cavity and an energetic material and a trigger mechanism disposed within the interior cavity, the trigger mechanism configured to selectively initiate the energetic material; and
 wherein the step of causing the elevated pressure event adequate to cause the at least one structurally weakened region to fail includes the trigger mechanism initiating the energetic material.   
     
     
         16 . The method of  claim 15 , wherein the at least one structurally weakened region is configured to fail in a manner that causes the frac-ball to rupture into discrete pieces upon initiation of the energetic material. 
     
     
         17 . The method of  claim 15 , wherein the at least one structurally weakened region is configured to fail in a manner that produces one or more fluid passages through the frac-ball upon initiation of the energetic material. 
     
     
         18 . The method of  claim 15 , wherein the frac-ball includes at least one wall having a thickness extending between an exterior surface and an interior surface, and the at least one structurally weakened region is a pocket disposed in the wall, which pocket results in a decreased wall thickness. 
     
     
         19 . The method of  claim 18 , wherein the at least one structurally weakened region has at least one physical characteristic different from a portion of the wall surrounding the structurally weakened region. 
     
     
         20 . The method of  claim 19 , wherein the at least one structurally weakened region possesses mechanical strength properties adequate to avoid failure within a range of predetermined well environment operating parameters and/or for a predetermined period of time in a well casing environment.