Packer Bridge Plug with Removable/Dissolvable Ball Seat

Abstract

A packer tool is provided having a moveable, resizeable or dissolvable ball seat. In the process of fracking, it is expensive to run tools into and out of the well. It is therefore desirable to run in tools that can serve multiple purposes during the fracking process. The present invention in at least one embodiment is therefore to a packer tool that can be used to seal a well bore and when the ball is removed presents only a small resistance to the production flow up through the plug. The removal of the ball is facilitated by removing the ball seat as an obstacle to the upward flow of the ball by dissolving, moving or resizing the ball seat.

1 . A packer bridge plug for sealing a well bore, comprising:
 a central, cylindrical body having a packer mounted thereto, said cylindrical body having an inner chamber extending axially therethrough;   a packer activator for axially compressing said packer to radially expand the packer about said cylindrical body;   a ball seat at a top end of said cylindrical body for selectively sealing said cylindrical body inner chamber from an area outside said inner chamber;   said ball seat selected from the group of dissolvable ball seats, axially moveable ball seats and expandable ball seats;   wherein when said bridge plug is activated and said packer is expanded about said cylindrical body, said packer bridge plug has a first, sealed position having a ball located on said ball seat and said ball seat has a smaller effective diameter than said ball to prevent flow in the mandrel from flowing from a first zone above the packer to a second zone below the packer, and has a second, production position wherein said ball seat has larger effective diameter than said ball allowing a ball to be pumped through said ball seat to allow flow through said cylindrical body inner chamber.   
     
     
         2 . The packer bridge plug of  claim 1 , wherein said ball seat is made from a dissolvable plastic. 
     
     
         3 . The packer bridge plug of  claim 1 , wherein said ball seat is an axially moveable ball seat. 
     
     
         4 . The packer bridge plug of  claim 1 , wherein said ball seat is an expandable ball seat. 
     
     
         5 . The packer bridge plug of  claim 1 , wherein cylindrical body has a first section defines a first inner diameter and a second section defines a second inner diameter than said first inner diameter, and
 wherein when said ball seat is pinned within said first, said ball seat has a first outer diameter, and when said ball seat is unpinned and moves axially to within said second section, said ball seat expands to a second, outer diameter.   
     
     
         6 . The packer bridge plug of  claim 1 , said cylindrical body having a second section intermediate a first and third section, wherein cylindrical body first section defines a first inner diameter and a second section defining a second inner diameter than said first inner diameter,
 wherein downward force on a ball on said ball seat moves said ball seat downward into contact with a ledge extending inwardly on said cylindrical body in said third section; and   wherein upward force on a second ball below said ball seat moves said ball seat upward into said third section, wherein when said ball seat is pinned within said first, said ball seat has a first outer diameter, and when said ball seat is unpinned and moves axially to within said second section, said ball seat expands to a second, outer diameter to allow said second ball to pass through said ball seat.   
     
     
         7 . The packer bridge plug of  claim 6 , wherein said ball seat is made from a dissolvable plastic. 
     
     
         8 . The packer bridge plug of  claim 6 , wherein said ball seat is an axially moveable ball seat. 
     
     
         9 . The packer bridge plug of  claim 6 , wherein said ball seat is an expandable ball seat.