Drop Balls for Use with Settable Downhole Tools

Abstract

Aspects of the present disclosed technology relate to drop balls and covers for drop balls for use with settable downhole tools. Aspects of the present disclosed technology also relate to methods for using such drop balls and covers with settable downhole tools to selectively allow fluid to pass through such downhole tools, or to block fluid flow through the settable downhole tool.

1 . A cage for use with a drop ball for a settable downhole tool, the cage comprising:
 a spherical pocket surrounded by a plurality of deformable segments of material,   wherein the plurality of deformable segments are arranged into a plurality of rings.   
     
     
         2 . The cage of  claim 1 , wherein the deformable segments have a durometer in the range of Shore A 60 to 100. 
     
     
         3 . The cage of  claim 1 , wherein the spherical pocket has a diameter between about 0.75 inches and about 4.375 inches. 
     
     
         4 . The cage of  claim 1 , wherein the plurality of deformable segments are arranged to form three mutually orthogonal rings around the spherical pocket. 
     
     
         5 . The cage of  claim 1 , wherein the plurality of deformable segments comprise a dissolvable material. 
     
     
         6 . A drop ball for use with a settable downhole tool, the drop ball comprising:
 a spherical body surrounded by a plurality of deformable segments of material,   wherein the plurality of deformable segments are arranged into a plurality of rings.   
     
     
         7 . The drop ball of  claim 6 , wherein the deformable segments have a durometer in the range of Shore A 60 to 100. 
     
     
         8 . The drop ball of  claim 6 , wherein the spherical pocket has a diameter between about 0.75 inches and about 4.375 inches. 
     
     
         9 . The drop ball of  claim 6 , wherein the plurality of deformable segments are arranged to form three mutually orthogonal rings around the spherical pocket. 
     
     
         10 . The drop ball of  claim 6 , wherein the spherical body is made of a first material, the deformable segments are made of a second material different than the first material, and the deformable segments are overmolded on the spherical body. 
     
     
         11 . The drop ball of  claim 6 , wherein the deformable segments have a durometer in the range of Shore A 60 to 100. 
     
     
         12 . The drop ball of  claim 6 , wherein the spherical body is comprised of a polymer acid. 
     
     
         13 . The drop ball of  claim 6 , wherein the spherical body is comprised of a first dissolvable material having a first dissolution rate, and the plurality of deformable segments are comprised of a second dissolvable material having a second dissolution rate. 
     
     
         14 . The drop ball of  claim 13 , wherein the second dissolution rate is faster than the first dissolution rate. 
     
     
         15 . A method for using a drop ball with a settable downhole tool, the method comprising:
 placing a drop ball on a seat located on an inner fluid channel of a settable downhole tool in a wellbore, wherein the drop ball comprises:
 a spherical body surrounded by a plurality of deformable segments of material, 
 wherein each of the deformable segments have a height measured from a boundary of the pocket to a point on the segment having a maximum radial distance from a center of the pocket, and 
 wherein an outer diameter of the drop ball including the deformable segments is greater than the seat; and 
   pumping a fluid through a wellbore at a first flow rate, wherein the fluid passes around the drop ball and through the inner channel of the downhole tool; and   pumping a fluid through a wellbore at a second flow rate, wherein the second flow rate is greater than the first flow rate, and wherein the deformable segments of material deform and a fluid-tight seal is formed between the seat and the drop ball, preventing a fluid flow through the inner channel of the settable downhole tool.   
     
     
         16 . The method of  claim 15 , wherein the deformable segments have a durometer in the range of Shore A 60 to 100. 
     
     
         17 . The method of  claim 15 , wherein the spherical pocket has a diameter between about 0.75 inches and about 4.375 inches. 
     
     
         18 . The method of  claim 15 , wherein the plurality of deformable segments are arranged to form three mutually orthogonal rings around the spherical pocket. 
     
     
         19 . The method of  claim 15 , wherein the spherical body is made of a first material, the deformable segments are made of a second material different than the first material, and the deformable segments are overmolded on the spherical body. 
     
     
         20 . The method of  claim 15 , wherein the first flow rate is less than about 20 barrels per minute.