← Back to Patent Explorer
US4285400A Expired / Lapsed US ⏱️ 0.0 years remaining

Releasing tool for pressure activated packer

Assignee: Baker International Corp
•
Filing: 1980-07-14
•
Granted: 1981-08-25
•
Expires: 2000-07-14
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A well bore packer which is run into a well casing on a tubing has actuator means responsive to applied fluid pressure to set anchor slips and to force a packing into engagement with the casing. The setting force is locked into the packing by a pressure balanced piston element having locking engagement with an inner body mandrel by a shear ring. A releasing tool is insertable within the bore of the body mandrel and incorporates an atmospheric pressure chamber. An operating mandrel for the releasing tool is shiftable through an increase in tubing pressure to establish communication between one side of the locking piston of the packer and the atmospheric chamber of the releasing tool, thus permitting the locking piston to shear the locking ring and free the setting forces operating on the packing elements of the packer.

Inventors

  • 👤 II Albert A. Mullins

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 11:49
CPC Classifications
E; E21; E21B; E21B23/00; E21B23/06; E21B33/00; E21B33/10; E21B33/12; E21B33/129; E21B33/1295

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.

References Cited (Backward Citations)

US3122205A Cited
US3142338A Cited
US3112796A Cited
US3131769A Cited
US3237695A Cited
US3282342A Cited
US3311171A Cited
US3746093A Cited
US4216827A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-08-24 1985-02-23 1985-08-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-08-24 1989-02-23 1989-08-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-08-24 1993-02-23 1993-08-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag