US3853177A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic subsurface blowout prevention
Assignee: Individual
•
Filing: 1973-04-19
•
Granted: 1974-12-10
•
Expires: 1993-04-19
Abstract
Abstract A tool and method for automatic subsurface closure of a well to prevent the uncontrolled flow of high-pressure formation fluids upward to the atmosphere while a well is being drilled or completed. The tool includes at least two main parts: A movable sealing means and a fluid flow control means positioned above the sealing means. The movable sealing means is used to shut in the well in response to a subsurface pressure condition. The fluid flow control means automatically provides an opening between the interior and exterior walls of the tool, when the pressure below the sealed off area is greater than the pressure above the sealed off area. The tool''s functions are automatic, reversible and repetitive.
Inventors
- 👤 J Mott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:35
CPC Classifications
E; E21; E21B; E21B21/00; E21B21/10; E21B33/00; E21B33/10; E21B33/12; E21B33/127; E21B34/00; E21B34/06; E21B34/08
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
230 words
A well tool for controlling a well having a borehole filled with a drilling fluid, said borehole extending through a geological structure which is susceptible of containing a formation fluid, the tool being adapted for insertion within a very long drill string which is lowered into the well bore, said tool comprising: a tubular member having an inner and an outer wall; a fluid-inflatable sleeve means mounted on said outer wall and being adapted to radially expand and to close off the annular area between the drill string and the borehole wall; fluid pressure control means mounted on said tubular member for controlling the expansion and contraction of said sleeve means, said control means defining: (1) a first fluid chamber fluidly communicating with said sleeve means, said first chamber being filled with a constant volume fluid, and (2) a second chamber fluidly communicating with the interior of said sleeve means and with said first chamber, said second chamber being positioned on said outer wall above said sleeve means; said control means including: a first piston movably mounted in said first chamber and a second piston mounted on said outer wall for moving said first piston in and out of said first chamber; and said sleeve means radially expanding when said first piston moves into said first chamber and radially contracting when said first piston moves out of said first chamber.
Claim 2
Dependent Claim
230 words
A well tool for controlling a well having a borehole filled with a drilling fluid, said borehole extending through a geological structure which is susceptible of containing a formation fluid, the tool being adapted for insertion within a very long drill string which is lowered into the well bore, said tool comprising: a tubular member having an inner and an outer wall; a fluid-inflatable sleeve means mounted on said outer wall and being adapted to radially expand and to close off the annular area between the drill string and the borehole wall; fluid pressure control means mounted on said tubular member for controlling the expansion and contraction of said sleeve means, said control means defining: (1) a first fluid chamber fluidly communicating with said sleeve means, said first chamber being filled with a constant volume fluid, and (2) a second chamber fluidly communicating with the interior of said sleeve means and with said first chamber, said second chamber being positioned on said outer wall above said sleeve means; said control means including: a first piston movably mounted in said first chamber and a second piston mounted on said outer wall for moving said first piston in and out of said first chamber; and said sleeve means radially expanding when said first piston moves into said first chamber and radially contracting when said first piston moves out of said first chamber.
Claim 3
Dependent Claim
230 words
A well tool for controlling a well having a borehole filled with a drilling fluid, said borehole extending through a geological structure which is susceptible of containing a formation fluid, the tool being adapted for insertion within a very long drill string which is lowered into the well bore, said tool comprising: a tubular member having an inner and an outer wall; a fluid-inflatable sleeve means mounted on said outer wall and being adapted to radially expand and to close off the annular area between the drill string and the borehole wall; fluid pressure control means mounted on said tubular member for controlling the expansion and contraction of said sleeve means, said control means defining: (1) a first fluid chamber fluidly communicating with said sleeve means, said first chamber being filled with a constant volume fluid, and (2) a second chamber fluidly communicating with the interior of said sleeve means and with said first chamber, said second chamber being positioned on said outer wall above said sleeve means; said control means including: a first piston movably mounted in said first chamber and a second piston mounted on said outer wall for moving said first piston in and out of said first chamber; and said sleeve means radially expanding when said first piston moves into said first chamber and radially contracting when said first piston moves out of said first chamber.
Claim 4
Dependent Claim
230 words
A well tool for controlling a well having a borehole filled with a drilling fluid, said borehole extending through a geological structure which is susceptible of containing a formation fluid, the tool being adapted for insertion within a very long drill string which is lowered into the well bore, said tool comprising: a tubular member having an inner and an outer wall; a fluid-inflatable sleeve means mounted on said outer wall and being adapted to radially expand and to close off the annular area between the drill string and the borehole wall; fluid pressure control means mounted on said tubular member for controlling the expansion and contraction of said sleeve means, said control means defining: (1) a first fluid chamber fluidly communicating with said sleeve means, said first chamber being filled with a constant volume fluid, and (2) a second chamber fluidly communicating with the interior of said sleeve means and with said first chamber, said second chamber being positioned on said outer wall above said sleeve means; said control means including: a first piston movably mounted in said first chamber and a second piston mounted on said outer wall for moving said first piston in and out of said first chamber; and said sleeve means radially expanding when said first piston moves into said first chamber and radially contracting when said first piston moves out of said first chamber.
Claim 5
Dependent Claim
55 words
The tool of claim 1 and further including: locking means mounted on said outer wall for releasably securing said first piston to said tubular member; and said second piston unlocking said locking means when the pressure of the fluid inside said tubular member is greater than the pressure of the fluid within said annular area.
Claim 6
Dependent Claim
36 words
The tool of claim 2 and further including; a first fluid passageway between said inner wall and said annular area above said sleeve means; and valve means for automatically controlling fluid flow through said first passageway.
Claim 7
Dependent Claim
66 words
The tool of claim 3 and further including: a third piston movably mounted in said second chamber, one surface of said third piston being responsive to the pressure inside said sleeve means and another surface being responsive to the pressure inside said tubular member; and said third piston moving out of said second chamber after said annular area below said sleeve means becomes effEctively sealed off.
Claim 8
Dependent Claim
34 words
The tool of claim 4 and further including: second sleeve means connected to said third piston; and said second sleeve means defining a valve surface which controls the fluid flow through said first passageway.
Claim 9
Dependent Claim
41 words
The tool of claim 5 and further including: a spring-biased floating piston mounted on said outer wall; and said floating piston assisting in moving said third piston downwardly into said second chamber when fluid communication through said passageway becomes cut off.
Claim 10
Dependent Claim
73 words
The tool of claim 6 and further defining: a second fluid passageway between said annular area and a surface of said second piston; a third fluid passageway between said annular area and said first piston; a fourth fluid passageway between said tubular member and a surface of said floating piston; and an opposite face of said floating piston being responsive to the fluid pressure in said annular area above said inflatable sleeve means.
Claim 11
Dependent Claim
35 words
The tool of claim 7 and further including: a shoulder securely mounted on said outer wall; a seal on said shoulder; and said seal snugly engaging said valve surface when said valve means is closed.
Claim 12
Independent Claim
173 words
A method for controlling a well having a borehole filled with a drilling fluid, said borehole extending through a geological structure which is susceptible of containing a formation of high-pressure fluid, and a very long drill string extending through said borehole, said method comprising: sealing off a portion of the annular area between said drill string and the borehole wall in response to subsurface differential pressures existing between the interior and exterior of said drill string; opening a fluid passageway between the interior of said drill string and said annular area above said sealed off portion in response to said differential pressures; circulating drilling fluid down said drill string through said passageway and up said annular area above said sealed off portion; increasing the weight of said drilling fluid; closing said fluid passageway in response to said differential pressures; and unsealing said previously sealed off portion when the weight of said drilling fluid reaches a sufficient level, thereby allowing drilling fluid to circulate down said drill string and up through said annular area.
Claim 13
Independent Claim
173 words
A method for controlling a well having a borehole filled with a drilling fluid, said borehole extending through a geological structure which is susceptible of containing a formation of high-pressure fluid, and a very long drill string extending through said borehole, said method comprising: sealing off a portion of the annular area between said drill string and the borehole wall in response to subsurface differential pressures existing between the interior and exterior of said drill string; opening a fluid passageway between the interior of said drill string and said annular area above said sealed off portion in response to said differential pressures; circulating drilling fluid down said drill string through said passageway and up said annular area above said sealed off portion; increasing the weight of said drilling fluid; closing said fluid passageway in response to said differential pressures; and unsealing said previously sealed off portion when the weight of said drilling fluid reaches a sufficient level, thereby allowing drilling fluid to circulate down said drill string and up through said annular area.
Claim 14
Dependent Claim
47 words
The tool of claim 10 including, disabling means coupled to said pressure control means adapted to disable said control means when said tool is initially inserted into said well bore, and said disabling means changing to enabling means after said tool becomes functional in said well bore.
Claim 15
Dependent Claim
36 words
The tool of claim 10 including, normally-closed first fluid communication means disposed above said sealing means, and said communication means being adapted to open for establishing fluid communication between the inside and outside of said tool.
Claim 16
Dependent Claim
20 words
The tool of claim 10 wherein, said first sensing element is a piston mounted on said mandrel for longitudinal movement.
Claim 17
Dependent Claim
31 words
The tool of claim 13 wherein, said control means include a movable mechanism controlled by said first sensing element; and said mechanism pressurizing or depressurizing the liquid in said first chamber.
Claim 18
Dependent Claim
32 words
The tool of claim 14 including, locking means for initially securing said mechanism to said mandrel, and said locking means releasing said mechanism after said tool becomes functional in said well bore.
Claim 19
Dependent Claim
26 words
The tool of claim 15 wherein the movement of said first sensing element exerts a downward force against said locking means to release said locking means.
Claim 20
Dependent Claim
21 words
The tool of claim 16 wherein said mechanism includes a piston adapted to move in or out of said first chamber.
Claim 21
Dependent Claim
23 words
The tool of claim 17 wherein said first communication means includes a circulating valve having a body portion coupled to said sealing means.
Claim 22
Dependent Claim
34 words
The tool of claim 18 wherein the first communication means includes a second differential-pressure sensing element movably mounted on said mandrel, and said second sensing element assisting in maintaining said circulating valve normally closed.
Claim 23
Dependent Claim
39 words
The tool of claim 19 wherein: said second sensing element is a piston movably mounted on said mandrel; and said sealing means includes an expandable element adapted to seal off said well bore when said first chamber becomes pressurized.
Claim 24
Dependent Claim
24 words
The tool of claim 20 including a check valve positioned near the bottom end of said mandrel to prevent fluid from entering said mandrel.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |