Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
158 words
A releasing tool for use in releasing a packer set in a well casing and having a normally pressure balanced annular releasing piston disposed in an annular chamber surrounding an inner annular mandrel body, and a pair of ports respectively connecting between the bore of the packer body and said annular chamber at opposite ends of said piston, said releasing tool comprising: a tubular housing insertable within the bore of the packer body; means within said tubular housing defining a first chamber at atmospheric pressure and a second chamber exposed by an external port to existing tubing pressure; spaced sealing means on said housing isolating one of said packer ports and connecting said isolated port to said second chamber port; and means responsive to an increase in tubing pressure to interconnect said first and second chambers, thereby producing a pressure imbalance on said packer releasing piston to effect said shifting of the releasing piston to release the packer.
Claim 2
Dependent Claim
158 words
A releasing tool for use in releasing a packer set in a well casing and having a normally pressure balanced annular releasing piston disposed in an annular chamber surrounding an inner annular mandrel body, and a pair of ports respectively connecting between the bore of the packer body and said annular chamber at opposite ends of said piston, said releasing tool comprising: a tubular housing insertable within the bore of the packer body; means within said tubular housing defining a first chamber at atmospheric pressure and a second chamber exposed by an external port to existing tubing pressure; spaced sealing means on said housing isolating one of said packer ports and connecting said isolated port to said second chamber port; and means responsive to an increase in tubing pressure to interconnect said first and second chambers, thereby producing a pressure imbalance on said packer releasing piston to effect said shifting of the releasing piston to release the packer.
Claim 3
Dependent Claim
206 words
A releasing tool for use in releasing a packer set in a well casing and having a normally pressure balanced annular releasing piston disposed in an annular chamber surrounding an inner mandrel body, and a pair of ports respectively connecting between the bore of the packer and said annular chamber at opposite ends of said piston, said releasing tool comprising: a tubular housing insertable within the bore of a packer; an axially shiftable tubular mandrel disposed within said tubular housing and defining in one axial position a first chamber at atmospheric pressure and a second chamber exposed by an external port to existing tubing pressure; shearable means for retaining said mandrel in said one position; spaced sealing means on said housing isolating one of said packer ports and connecting said isolated ports to said second chamber port; means in said axially shiftable mandrel for blocking fluid passage therethrough, whereby tubing pressure may be increased to exert sufficient force on said axially shiftable mandrel to shear said shearable means and move said mandrel to a second position wherein said first and second chambers are interconnected, thereby producing a pressure imbalance on said packer releasing piston to effect said shifting of the releasing piston to release the packer.
Claim 4
Dependent Claim
206 words
A releasing tool for use in releasing a packer set in a well casing and having a normally pressure balanced annular releasing piston disposed in an annular chamber surrounding an inner mandrel body, and a pair of ports respectively connecting between the bore of the packer and said annular chamber at opposite ends of said piston, said releasing tool comprising: a tubular housing insertable within the bore of a packer; an axially shiftable tubular mandrel disposed within said tubular housing and defining in one axial position a first chamber at atmospheric pressure and a second chamber exposed by an external port to existing tubing pressure; shearable means for retaining said mandrel in said one position; spaced sealing means on said housing isolating one of said packer ports and connecting said isolated ports to said second chamber port; means in said axially shiftable mandrel for blocking fluid passage therethrough, whereby tubing pressure may be increased to exert sufficient force on said axially shiftable mandrel to shear said shearable means and move said mandrel to a second position wherein said first and second chambers are interconnected, thereby producing a pressure imbalance on said packer releasing piston to effect said shifting of the releasing piston to release the packer.
Claim 5
Dependent Claim
14 words
The releasing tool of claim 2 wherein said blocking means comprises a check valve.
Claim 6
Dependent Claim
36 words
The releasing tool of claim 2 wherein the inner wall of said axially shiftable tubular mandrel is inwardly constricted to form an annular valve seat, and a check valve member gravitationally rests on said valve seat.
Claim 7
Dependent Claim
33 words
The releasing tool of claim 4 wherein said shearable means comprises a shear pin traversing said tubular mandrel above said check valve member to limit upward displacement thereof from said annular valve seat.