US3794965A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Marine seismic cable buoyancy system
Assignee: ExxonMobil Upstream Research Co
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Filing: 1972-09-18
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Granted: 1974-02-26
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Expires: 1992-09-18
Abstract
Abstract The buoyancy of a marine seismic cable is controlled by transferring water into and out of individual buoyancy units located between sections of the cable. Each buoyancy unit includes a chamber containing a confined gas maintained at a pressure greater than ambient water pressure, a pump for introducing water into the chamber, and means for expelling water as necessary. A control system which permits both manual and automatic adjustments of the cable buoyancy is provided. This makes possible the towing of the cable at essentially constant depths behind an initial cable section fitted with a depth controller.
Inventors
- 👤 C Charske
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:56
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/38; G01V1/3817; G01V1/3826; B; B63; B63G; B63G8/00; B63G8/42; G01V1/16; G01V1/20; G01V1/201; G01V2001/207
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
118 words
A method for controlling the buoyancy of a marine seismic cable provided with a lead-in section as said cable is towed through a body of water which comprises monitoring the depth of said cable at a plurality of points along the length of said cable; introducing water from said body of water into at least one of a plurality of buoyancy chambers located at intervals along the length of said cable behind said lead-in section when a reduction in buoyancy is required, each of said buoyancy chambers containing a gas confined to said chamber; and expelling water from at least one of said buoyancy chambers into the surrounding body of water when an increase in buoyancy is required.
Claim 2
Independent Claim
118 words
A method for controlling the buoyancy of a marine seismic cable provided with a lead-in section as said cable is towed through a body of water which comprises monitoring the depth of said cable at a plurality of points along the length of said cable; introducing water from said body of water into at least one of a plurality of buoyancy chambers located at intervals along the length of said cable behind said lead-in section when a reduction in buoyancy is required, each of said buoyancy chambers containing a gas confined to said chamber; and expelling water from at least one of said buoyancy chambers into the surrounding body of water when an increase in buoyancy is required.
Claim 3
Dependent Claim
19 words
A method as defined by claim 1 wherein said water is introduced by pumping water into said buoyancy chamber.
Claim 4
Dependent Claim
33 words
A method as defined by claim 1 wherein said gas in said buoyancy chamber is maintained at a pressure greater than hydrostatic and said water is expelled by permitting said gas to expand.
Claim 5
Dependent Claim
30 words
A method as defined by claim 1 wherein said gas in said buoyancy chamber is maintained at a pressure less than hydrostatic and said water is introduced under hydrostatic pressure.
Claim 6
Dependent Claim
24 words
A method as defined by claim 1 wherein said water is expelled by pumping water from said buoyancy chamber into said body of water.
Claim 7
Independent Claim
147 words
A method for controlling the position of a marine seismic cable during seismic prospecting operations carried out in a body of water which comprises towing said cable through said body of water, said cable including a lead-in section fitted with a depth controller; monitoring the hydrostatic pressure on said cable at a plurality of positions along the cable length behind said lead-In section; pumping water from said body of water into at least one of a plurality of individual buoyancy chambers located at intervals along the length of said cable behind said lead-in section in response to a reduction in hydrostatic pressure on said cable, each of said buoyancy chambers containing a gas confined to said chamber at a pressure in excess of hydrostatic pressure; and expelling water from at least one of said buoyancy chambers in response to an increase in hydrostatic pressure on said cable.
Claim 8
Independent Claim
147 words
A method for controlling the position of a marine seismic cable during seismic prospecting operations carried out in a body of water which comprises towing said cable through said body of water, said cable including a lead-in section fitted with a depth controller; monitoring the hydrostatic pressure on said cable at a plurality of positions along the cable length behind said lead-In section; pumping water from said body of water into at least one of a plurality of individual buoyancy chambers located at intervals along the length of said cable behind said lead-in section in response to a reduction in hydrostatic pressure on said cable, each of said buoyancy chambers containing a gas confined to said chamber at a pressure in excess of hydrostatic pressure; and expelling water from at least one of said buoyancy chambers in response to an increase in hydrostatic pressure on said cable.
Claim 9
Dependent Claim
20 words
A method as defined by claim 6 wherein said cable is towed behind a lead-in section fitted with a paravane.
Claim 10
Dependent Claim
30 words
A method as defined by claim 6 wherein said water is expelled from said buoyancy chamber by venting said chamber to the surrounding water and permitting said gas to expand.
Claim 11
Dependent Claim
23 words
A method as defined by claim 6 wherein said water is expelled by pumping water from said buoyancy chamber into the surrounding water.
Claim 12
Dependent Claim
30 words
A method as defined by claim 6 wherein said water is pumped separately into each of a plurality of buoyancy chambers spaced at intervals along the length of said cable.
Claim 13
Dependent Claim
90 words
Apparatus for controlling the buoyancy of a marine seismic cable which comprises an outer housing containing an internal buoyancy chamber; an expansion member positioned within said buoyancy chamber for confining a gas within a portion of said chamber; a pump located in said housing, said pump communicating with a water inlet port in the housing wall and with a water discharge port in said buoyancy chamber; means in said housing for actuating said pump; and means for connecting said housing in place between adjacent sections of said marine seismic cable.
Claim 14
Dependent Claim
90 words
Apparatus for controlling the buoyancy of a marine seismic cable which comprises an outer housing containing an internal buoyancy chamber; an expansion member positioned within said buoyancy chamber for confining a gas within a portion of said chamber; a pump located in said housing, said pump communicating with a water inlet port in the housing wall and with a water discharge port in said buoyancy chamber; means in said housing for actuating said pump; and means for connecting said housing in place between adjacent sections of said marine seismic cable.
Claim 15
Dependent Claim
18 words
Apparatus as defined by claim 11 wherein said expansion member comprises a collapsible bladder surrounding said discharge port.
Claim 16
Dependent Claim
34 words
Apparatus as defined by claim 12 including a bypass valve communicating with the interior of said bladder and with the exterior of said housing and means within said housing for actuating said bypass valve.
Claim 17
Dependent Claim
13 words
Apparatus as defined by claim 11 wherein said pump is a reversible pump.
Claim 18
Dependent Claim
131 words
A buoyancy controller for use with a marine seismic cable which comprises an elongated outer housing containing an internal buoyancy chamber having a gas inlet near one end thereof and a water inlet near the other end thereof; an elongated inflatable member positioned about said water inlet in said buoyancy chamber; a pump in said housing communicating with said water inlet in said buoyancy chamber and with an inlet port in the outer wall of said housing; a bypass valve in said housing communicating with said water inlet in said buoyancy chamber and with an outlet in the outer wall of said housing; electrical means in said housing for selectively actuating said pump and said bypass valve; and means for connecting said housing between adjacent sections of said marine seismic cable.
Claim 19
Dependent Claim
131 words
A buoyancy controller for use with a marine seismic cable which comprises an elongated outer housing containing an internal buoyancy chamber having a gas inlet near one end thereof and a water inlet near the other end thereof; an elongated inflatable member positioned about said water inlet in said buoyancy chamber; a pump in said housing communicating with said water inlet in said buoyancy chamber and with an inlet port in the outer wall of said housing; a bypass valve in said housing communicating with said water inlet in said buoyancy chamber and with an outlet in the outer wall of said housing; electrical means in said housing for selectively actuating said pump and said bypass valve; and means for connecting said housing between adjacent sections of said marine seismic cable.
Claim 20
Dependent Claim
45 words
A buoyancy controller as defined by claim 15 wherein said electrical means for actuating said pump and bypass valve includes an electric motor connected to said pump, an electric motor connected to said bypass valve, and means for connecting said motors to shipboard control devices.
Claim 21
Dependent Claim
36 words
A buoyancy controller as defined by claim 16 wherein said electrical means for actuating said pump bypass valve further includes batteries in said housing and means for connecting said batteries to a shipboard trickle charge source.
Claim 22
Dependent Claim
57 words
A buoyancy controller as defined by claim 16 including a pressure comparator in said housing communicating with said gas inlet in said buoyancy chamber, said pressure comparator including a gas pressure calibration chamber, a piston positioned between said calibration chamber and said gas inlet, and switches actuated by said piston for energizing said pump and valve motors.
Claim 23
Dependent Claim
22 words
A buoyancy controller as defined by claim 15 including a water filter in said housing between said inlet port and said pump.
Claim 24
Dependent Claim
27 words
A buoyancy controller as defined by claim 15 including a hydrostatic pressure sensor in said housing and means for connecting said pressure sensor to a shipboard indicator.
References Cited (Backward Citations)
US3673556A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-25 | 1977-08-27 | 1978-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-25 | 1981-08-27 | 1982-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-25 | 1985-08-27 | 1986-02-26 | $7700.00 | Window Closed / Lapsed |