US3786867A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Well safety valve system and method of operation
Assignee: CAMCO INC US
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Filing: 1973-02-23
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Granted: 1974-01-22
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Expires: 1993-02-23
Abstract
Abstract A well safety valve which is controlled through a control line leading to the surface which can be set at greater depths in the well by limiting the hydrostatic liquid head in the control line by using gas in the control line and temporarily opening the control line adjacent the lower end for draining the control line of accumulated liquids. Pressurizing the control line with gas while the lower end of the line is open to drive out any liquid therein. A normally closed opening in the control line adjacent the safety valve with means for opening and closing the opening for normally closing the opening for allowing control of the safety valve, but for opening the opening draining any accumulated liquids. A passageway connected between the safety valve and the opening and closing means. The opening and closing means may include various mechanisms such as a sliding sleeve or a sidepocket mandrel having flow control means in the sidepocket for controlling the opening of the passageway.
Inventors
- 👤 G Tausch
- 👤 F Watkins
- 👤 W Dietz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:29
CPC Classifications
E; E21; E21B; E21B34/00; E21B34/06; E21B34/10; E21B34/105; E21B34/107
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
138 words
In a well saFety valve for controlling the fluid flow through a well tubing, the valve having a valve closure member moving between open and closed positions, means biasing the valve to a closed position, and a control line leading to the well surface for controlling the actuation of the valve by pressure in the control line, the improvement of means for allowing the safety valve to be used at greater depths by limiting any undesirable hydrostatic liquid head in the control line comprising, said fluid in the control line being a gas, and a normally closed opening in the control line at a point adjacent the safety valve, and means for opening and closing said opening for draining the control line of any liquid accumulated therein thereby limiting any undesirable hydrostatic liquid head in the control line.
Claim 2
Dependent Claim
138 words
In a well saFety valve for controlling the fluid flow through a well tubing, the valve having a valve closure member moving between open and closed positions, means biasing the valve to a closed position, and a control line leading to the well surface for controlling the actuation of the valve by pressure in the control line, the improvement of means for allowing the safety valve to be used at greater depths by limiting any undesirable hydrostatic liquid head in the control line comprising, said fluid in the control line being a gas, and a normally closed opening in the control line at a point adjacent the safety valve, and means for opening and closing said opening for draining the control line of any liquid accumulated therein thereby limiting any undesirable hydrostatic liquid head in the control line.
Claim 3
Dependent Claim
129 words
In a well safety valve for controlling the fluid flow through a well tubing, the valve having a valve closure member moving between open and closed positions, means biasing the valve to a closed position, and a control line leading to the well surface for controlling the actuation of the valve pressure in the control line, the improvement of means for allowing the safety valve to be utilized at greater depths by limiting any undesirable hydrostatic liquid head in the control line comprising, said fluid in the control line being a gas, a passageway in communication between the control line at a point adjacent the safety valve and the interior of the well tubing, and means for opening and closing said passageway for draining liquid from the control line.
Claim 4
Dependent Claim
129 words
In a well safety valve for controlling the fluid flow through a well tubing, the valve having a valve closure member moving between open and closed positions, means biasing the valve to a closed position, and a control line leading to the well surface for controlling the actuation of the valve pressure in the control line, the improvement of means for allowing the safety valve to be utilized at greater depths by limiting any undesirable hydrostatic liquid head in the control line comprising, said fluid in the control line being a gas, a passageway in communication between the control line at a point adjacent the safety valve and the interior of the well tubing, and means for opening and closing said passageway for draining liquid from the control line.
Claim 5
Dependent Claim
20 words
The apparatus of claim 2 wherein the opening and closing means includes, a sliding sleeve positioned in the well tubing.
Claim 6
Dependent Claim
44 words
The apparatus of claim 2 wherein the opening and closing means includes, a sidepocket mandrel positioned in the well tubing in which the sidepocket is connected to the passageway, and flow control means positioned in the sidepocket for controlling the opening of said passageway.
Claim 7
Dependent Claim
35 words
The apparatus of claim 2 wherein the control line is connected to the safety valve and the passageway is connected to the safety valve and in communication with the lower end of the control line.
Claim 8
Dependent Claim
183 words
In a well safety valve for controlling the fluid flow through a well tubing, the valve positioned in the tubing and having a valve closure member moving between open and closed positions, a longitudinally movable tubular member for controlling the movement of the valve closure member, means for biasing the tubular member in a first direction, pressure means for moving the tubular member in direction for opening the valve, a control conduit leading from the well surface to the pressure means for controlling the actuation of the valve, the improvement of means for allowing the safety valve to be used at greater depths by limiting any undesirable hydrostatic liquid in the control line comprising, said fluid in the control line being a gas, a passageway in communication between the control line at a point adjacent the safety valve and the interior of the well tubing, means in the well tubing normally closing said passageway for allowing control of the safety valve by gas pressure in the control line, but for temporarily opening said passageway for draining any liquid accumulated in the control line.
Claim 9
Dependent Claim
183 words
In a well safety valve for controlling the fluid flow through a well tubing, the valve positioned in the tubing and having a valve closure member moving between open and closed positions, a longitudinally movable tubular member for controlling the movement of the valve closure member, means for biasing the tubular member in a first direction, pressure means for moving the tubular member in direction for opening the valve, a control conduit leading from the well surface to the pressure means for controlling the actuation of the valve, the improvement of means for allowing the safety valve to be used at greater depths by limiting any undesirable hydrostatic liquid in the control line comprising, said fluid in the control line being a gas, a passageway in communication between the control line at a point adjacent the safety valve and the interior of the well tubing, means in the well tubing normally closing said passageway for allowing control of the safety valve by gas pressure in the control line, but for temporarily opening said passageway for draining any liquid accumulated in the control line.
Claim 10
Dependent Claim
24 words
the apparatus of claim 6 wherein the closing and opening means includes, a sliding sleeve positioned in the well tubing above the safety valve.
Claim 11
Dependent Claim
36 words
The apparatus of claim 6 wherein the closing and opening means is positioned in the well tubing above the safety valve, and said passageway is connected between the safety valve and the closing and opening means.
Claim 12
Dependent Claim
48 words
The apparatus of claim 6 wherein the closing and opening means includes, a sidepocket mandrel positioned in the well tubing above the safety valve and in which the sidepocket is connected to the passageway, flow control means positioned in the sidepocket for controlling the opening of said passAgeway.
Claim 13
Dependent Claim
18 words
The apparatus of claim 9 wherein the flow control means includes, means for opening on a predetermined pressure.
Claim 14
Independent Claim
100 words
The method of limiting the hydrostatic head in the fluid control line leading from the surface and controlling the actuation of a safety valve in a well tubing comprising, controlling the safety valve from the surface through the control line by using gas in the control line for limiting the hydrostatic head in the control line, and opening the control line adjacent the lower end of the control line for draining the control line of liquids accumulating therein for avoiding an undesirable hydrostatic liquid head in the control line thereby allowing the safety valve to be used at greater depths.
Claim 15
Independent Claim
100 words
The method of limiting the hydrostatic head in the fluid control line leading from the surface and controlling the actuation of a safety valve in a well tubing comprising, controlling the safety valve from the surface through the control line by using gas in the control line for limiting the hydrostatic head in the control line, and opening the control line adjacent the lower end of the control line for draining the control line of liquids accumulating therein for avoiding an undesirable hydrostatic liquid head in the control line thereby allowing the safety valve to be used at greater depths.
Claim 16
Dependent Claim
18 words
The method of claim 11 including, opening the control line upon a predetermined pressure in the control line.
Claim 17
Dependent Claim
22 words
The method of claim 11 including, pressurizing the control line with gas when the lower end of the control line is opened.
Claim 18
Independent Claim
81 words
The method of controlling fluid flow through a well tubing comprising, placing a safety valve in the well tubing below the well surface, controlling the actuation of the safety valve by gas from the surface through a control line thereby limiting the hydrostatic head in the control line, temporarily opening the control line adjacent the lower end of the control line for draining the control line of liquids accumulating therein for avoiding an undesirable hydrostatic liquid head in the control line.
Claim 19
Independent Claim
81 words
The method of controlling fluid flow through a well tubing comprising, placing a safety valve in the well tubing below the well surface, controlling the actuation of the safety valve by gas from the surface through a control line thereby limiting the hydrostatic head in the control line, temporarily opening the control line adjacent the lower end of the control line for draining the control line of liquids accumulating therein for avoiding an undesirable hydrostatic liquid head in the control line.
Claim 20
Dependent Claim
21 words
The method of claim 14 including, pressurizing the control line with gas while the lower end of the line is open.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |