US3749162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arctic oil and gas development
Assignee: Global Marine Inc
•
Filing: 1971-04-01
•
Granted: 1973-07-31
•
Expires: 1991-04-01
Abstract
Abstract In performing oil and gas exploration and production operations in arctic regions in association with submerged well sites, a shallow draft barge equipped with appropriate mechanisms and devices is used. During periods when no ice is present over the submerged well site, the barge is moored over the well site. During periods in which ice sheets overlie the submerged well site, the barge is buoyantly supported in a pool of water which communicates through the ice sheet. As the ice sheet moves laterally relative to the submerged well site, the position of the pool is moved in the ice sheet so that the location of the barge is maintained over the location of the submerged well site within limits appropriate to the nature of the operations being performed at the submerged well site. Movement of the water pool within the moving ice sheet is accomplished by melting the boundaries of the water pool lying between the barge and the direction from which the ice sheet moves toward the barge at a rate equal to the rate of movement of the ice sheet relative to the submerged well site. The barge is movable across the top of the ice sheet, or across water or land, to and from well site locations on a cushion of low pressure air. The barge may also be used as a land based site of oil or gas well drilling or production operations.
Inventors
- 👤 E Anders
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:18
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/01; E21B7/00; E21B7/008; E21B7/12; F; F02; F02B; F02B1/00; F02B1/02; F02B1/04; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 96
Claim 1
Independent Claim
119 words
A method for maintaining a floating structure in a substantially fixed position in a pool within ice subject to lateral motion irrespective of ice motion, the structure being free of any significant mooring connection to the bottom of a body of water over which the ice is formed, the method comprising the step of: effectively moving the pool laterally in the ice in a direction opposite to the direction of ice motion at a rate substantially equal to the rate of ice motion by applying sufficient energy from within the floating structure to the ice defining a lateral boundary of the pool on a side thereof opposite the direction of ice motion to Reduce said boundary at said rate.
Claim 2
Independent Claim
119 words
A method for maintaining a floating structure in a substantially fixed position in a pool within ice subject to lateral motion irrespective of ice motion, the structure being free of any significant mooring connection to the bottom of a body of water over which the ice is formed, the method comprising the step of: effectively moving the pool laterally in the ice in a direction opposite to the direction of ice motion at a rate substantially equal to the rate of ice motion by applying sufficient energy from within the floating structure to the ice defining a lateral boundary of the pool on a side thereof opposite the direction of ice motion to Reduce said boundary at said rate.
Claim 3
Dependent Claim
21 words
The method according to claim 1 including applying said energy to the ice through the submerged portions of the floating structure.
Claim 4
Dependent Claim
26 words
The method according to claim 1 including moving the floating structure relative to the ice in said opposite direction in conjunction with the pool movement process.
Claim 5
Dependent Claim
17 words
The method according to claim 1 wherein said energy comprises mechanical energy applied to erode said ice.
Claim 6
Dependent Claim
21 words
The method according to claim 1 wherein said energy comprises chemical energy applied to lower the melting point of said ice.
Claim 7
Dependent Claim
16 words
The method according to claim 1 wherein said energy comprises heat applied to melt said ice.
Claim 8
Dependent Claim
46 words
The method according to claim 6 including the step of controlling the rate at which heat is applied to those lateral boundaries of the pool which move toward the floating structure in proportion to the rate at which said boundaries move normal to the floating structure.
Claim 9
Dependent Claim
20 words
The method according to claim 6 including heating at least a portion of the submerged surfaces of the floating structure.
Claim 10
Dependent Claim
36 words
The method according to claim 6 wherein heat is applied from the floating structure to the ice by directing streams of warm water outwardly from at least some of the submerged surfaces of the floating structure.
Claim 11
Independent Claim
200 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice susceptible of movement relative to said location comprising the steps of: a. providing a buoyant platform from which desired operations may be performed, b. buoyantly floating the platform in a pool of water communicating through the ice sheet over the submerged location free of any significant mooring connection of the platform to the bottom of the body of water over which the ice is formed, c. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state, and d. maintaining the position of the pool over the submerged location, during movement of the ice sheet relative to the submerged location, within limits appropriate to the operations performed at and in association with the submerged location by applying energy from within the platform through at least one submerged location thereof to those boundary surfaces of the pool between the platform and the direction from which the ice sheet moves relative to the submerged location thereby to remove said boundary surfaces and effectively move the pool within the ice sheet.
Claim 12
Independent Claim
200 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice susceptible of movement relative to said location comprising the steps of: a. providing a buoyant platform from which desired operations may be performed, b. buoyantly floating the platform in a pool of water communicating through the ice sheet over the submerged location free of any significant mooring connection of the platform to the bottom of the body of water over which the ice is formed, c. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state, and d. maintaining the position of the pool over the submerged location, during movement of the ice sheet relative to the submerged location, within limits appropriate to the operations performed at and in association with the submerged location by applying energy from within the platform through at least one submerged location thereof to those boundary surfaces of the pool between the platform and the direction from which the ice sheet moves relative to the submerged location thereby to remove said boundary surfaces and effectively move the pool within the ice sheet.
Claim 13
Dependent Claim
52 words
The method according to claim 10 wherein the desired operations include establishing a well at the submerged location, and including maintaining the position of the pool over the well within a horizontal distance equal to about 10 percent of the water depth between the water surface in the pool and submerged location.
Claim 14
Dependent Claim
33 words
The method according to claim 10 wherein an oil well exists at the submerged location, and the desired operations performed from the platform include the step of production of oil from the well.
Claim 15
Dependent Claim
25 words
The method according to claim 10 including the step of moving the platform into position on a cushion of air to above the submerged location.
Claim 16
Dependent Claim
49 words
The method according to claim 10 wherein the pool of water is defined in the upper extent of the ice sheet, and maintaining communication between the pool and the water below the ice sheet through the ice sheet from at least a portion of the bottom of the pool.
Claim 17
Dependent Claim
21 words
The method according to claim 14 wherein said communication is maintained through a hole in the ice sheet below the platform.
Claim 18
Dependent Claim
17 words
The method according to claim 15 including performing the desired operations at least partially through said hole.
Claim 19
Dependent Claim
51 words
The method according to claim 10 wherein the step of maintaining the position of the pool includes moving the platform relative to the ice sheet in a direction opposite to and at a rate equal to the direction and rate of movement of the ice sheet relAtive to the submerged location.
Claim 20
Dependent Claim
56 words
The method according to claim 17 wherein the platform is moved relative to the ice sheet by connecting mooring lines between the platform and corresponding anchor points in the ice sheet spaced from the platform in substantially orthogonal horizontal directions about the platform, and selectively taking in and paying out said mooring lines from the platform.
Claim 21
Dependent Claim
22 words
The method according to claim 10 wherein the energy-applying process includes applying heat from internally of the platform to the ice sheet.
Claim 22
Dependent Claim
42 words
The method according to claim 19 including controlling the rate at which heat is applied to those boundary surfaces of the pool which move toward the platform in proportion to the rate at which said boundary surfaces move normal to the platform.
Claim 23
Dependent Claim
19 words
The method according to claim 19 including heating at least a portion of the submerged surfaces of the platform.
Claim 24
Dependent Claim
35 words
The method according to claim 19 wherein heat is applied from the platform to the ice sheet by directing streams of warm water outwardly from at least some of the submerged surfaces of the platform.
Claim 25
Dependent Claim
27 words
The method according to claim 22 including mixing in said warm water streams a quantity of a substance which functions to reduce the freezing point of water.
Claim 26
Dependent Claim
19 words
The method according to claim 10 wherein the ice removal process includes eroding the boundary surfaces of the pool.
Claim 27
Dependent Claim
25 words
The method according to claim 24 wherein the erosion process is accomplished by directing from the platform to said pool boundary surfaces streams of water.
Claim 28
Dependent Claim
23 words
The method according to claim 10 including thickening the ice sheet circumferentially of the pool for a selected distance laterally from the pool.
Claim 29
Dependent Claim
37 words
The method according to claim 26 wherein the ice thickening step is performed by applying water over the upper surface of the ice sheet in the area to be thickened and allowing the applied water to freeze.
Claim 30
Independent Claim
148 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice susceptible of movement relative to said location comprising the steps of: a. providing a buoyant platform from which desired operations may be performed and which has a weight greater than that capable of being supported by the sheet of ice; b. establishing a pool of water communicating through the ice sheet over the submerged location by applying the weight of the platform directly to the ice sheet; c. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state; and d. maintaining the position of the pool over the submerged location, during movement of the ice sheet relative to the submerged locations, within limits appropriate to the operations performed and in association with the submerged location.
Claim 31
Independent Claim
148 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice susceptible of movement relative to said location comprising the steps of: a. providing a buoyant platform from which desired operations may be performed and which has a weight greater than that capable of being supported by the sheet of ice; b. establishing a pool of water communicating through the ice sheet over the submerged location by applying the weight of the platform directly to the ice sheet; c. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state; and d. maintaining the position of the pool over the submerged location, during movement of the ice sheet relative to the submerged locations, within limits appropriate to the operations performed and in association with the submerged location.
Claim 32
Dependent Claim
35 words
The method according to claim 28 including the further step of ballasting the platform following positioning of the platform on the ice sheet over the submerged location to increase the effective weight of the platform.
Claim 33
Dependent Claim
25 words
The method according to claim 28 including heating the ice surfaces adjacent the platform by applying heat from internally of the platform to the ice.
Claim 34
Independent Claim
146 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice susceptible of movement relative to said location comprising the steps of: a. providing a buoyant platform from which desired operations may be performed, b. establishing in the ice over the submerged location a pool of water communicating through the ice sheet, c. moving the platform into position over the submerged location on a cushion of air, d. buoyantly floating the platform in the pool, e. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state, and f. maintaining the position of the pool over the submerged location, during movement of the ice sheet relative to the submerged location, within limits appropriate to the operations performed at and in association with the submerged location.
Claim 35
Independent Claim
146 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice susceptible of movement relative to said location comprising the steps of: a. providing a buoyant platform from which desired operations may be performed, b. establishing in the ice over the submerged location a pool of water communicating through the ice sheet, c. moving the platform into position over the submerged location on a cushion of air, d. buoyantly floating the platform in the pool, e. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state, and f. maintaining the position of the pool over the submerged location, during movement of the ice sheet relative to the submerged location, within limits appropriate to the operations performed at and in association with the submerged location.
Claim 36
Dependent Claim
31 words
The method according to claim 31 including the step of providing the pool in the upper extent of the ice sheet before moving the platform into position over the submerged location.
Claim 37
Dependent Claim
50 words
The method according to claim 32 wherein the pool is formed by explosively fragmenting a volume of ice in the upper extent of the ice sheet corresponding in shape and extent to the pool, and forming a hole through the remainder of the ice sheet thereby to form the pool.
Claim 38
Dependent Claim
21 words
The method according to claim 33 wherein the hole is formed essentially simultaneously with the fragmenting of said volume of ice.
Claim 39
Dependent Claim
51 words
The method according to claim 32 wherein the pool is formed by excavating from the upper extent of the ice sheet a volume of ice corresponding to the shape and depth of the pool, and forming a hole through the ice sheet downwardly from the excavation thereby to flood the pool.
Claim 40
Dependent Claim
37 words
The method according to claim 35 including defining the excavation at least to a depth equal to the sum of 12 percent of the ice sheet thickness and the draft of the platform in a buoyant state.
Claim 41
Dependent Claim
26 words
The method according to claim 35 including moving the platform into the excavation prior to forming the hole through the ice sheet downwardly from the excavation.
Claim 42
Dependent Claim
35 words
The method according to claim 37 including providing a ramp in the ice sheet from the upper surface thereof to the bottom of the excavation, and moving the platform down the ramp into the excavation.
Claim 43
Dependent Claim
35 words
The method according to claim 38 including sealing the ramp from the excavation following movement of the platform into the excavation and prior to forming the hole through the ice sheet downwardly from the excavation.
Claim 44
Dependent Claim
34 words
The method according to claim 39 including removing the seal between the ramp and the excavation upon completion of operations from the platform, and moving the platform out of the excavation up the ramp.
Claim 45
Dependent Claim
34 words
The method according to claim 40 wherein the seal between the ramp and the excavation is defined by a wall of ice, and the seal is removed by fragmenting the ice wall with explosives.
Claim 46
Dependent Claim
22 words
The method according to claim 40 including moving the platform up the ramp by winching the platform relative to the ice sheet.
Claim 47
Dependent Claim
27 words
The method according to claim 42 including melting the ice surface under the platform during movement of the platform out of the excavation and up the ramp.
Claim 48
Independent Claim
118 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice comprising the steps of: a. providing a buoyant platform from which desired operations may be performed, b. buoyantly floating the platform in a pool of water communicating through the ice sheet over the submerged location, c. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state, and d. thickening the ice sheet circumferentially of the pool for a selected distance laterally from the pool by an amount adequate to compensate for the stress concentrating effect of the presence of the pool in the ice sheet.
Claim 49
Independent Claim
118 words
A method of performing operations at and in association with a submerged marine location overlaid by a sheet of ice comprising the steps of: a. providing a buoyant platform from which desired operations may be performed, b. buoyantly floating the platform in a pool of water communicating through the ice sheet over the submerged location, c. performing desired operations at and in association with the submerged location from the platform while the same is in a buoyantly floating state, and d. thickening the ice sheet circumferentially of the pool for a selected distance laterally from the pool by an amount adequate to compensate for the stress concentrating effect of the presence of the pool in the ice sheet.
Claim 50
Dependent Claim
41 words
The method according to claim 44 wherein the ice sheet is thickened by applying the water to the upper surface of the ice sheet over the area to be thickened, and allowing the applied water to freeze to the ice sheet.
Claim 51
Dependent Claim
96 words
A buoyant structure for use in waters covered by a layer of ice comprising a buoyant hull floatable in a pool formed in the ice, and means for directing energy from a source carried by the hull outwardly from the submerged surfaces thereof in any desired direction to ice defining an adjacent boundary of the pool in an amount sufficient for removing ice at a rate that permits the hull to remain in a substantially fixed position in a movable layer of ice irrespective of the direcTion of movement of the ice relative to the hull.
Claim 52
Dependent Claim
96 words
A buoyant structure for use in waters covered by a layer of ice comprising a buoyant hull floatable in a pool formed in the ice, and means for directing energy from a source carried by the hull outwardly from the submerged surfaces thereof in any desired direction to ice defining an adjacent boundary of the pool in an amount sufficient for removing ice at a rate that permits the hull to remain in a substantially fixed position in a movable layer of ice irrespective of the direcTion of movement of the ice relative to the hull.
Claim 53
Dependent Claim
18 words
Apparatus according to claim 46 wherein the energy-directing means is arranged to apply heat energy to the ice.
Claim 54
Dependent Claim
63 words
Apparatus according to claim 47 including means for transferring heat through the bottom surfaces of the hull in an amount sufficient to maintain the hull buoyant in a pool having a depth less than the thickness of an ice sheet in which the pool is formed, and means for maintaining liquid communication through the ice layer from the pool to the underlying water.
Claim 55
Dependent Claim
49 words
Apparatus according to claim 47 wherein the means for directing energy comprises a gas turbine, means for discharging at least one stream of water through the hull to the ice, and means for mixing at least a portion of the exhaust from the gas turbine with said water stream.
Claim 56
Dependent Claim
28 words
Apparatus according to claim 49 including means for adding to the water stream a quantity of a substance which is effective to lower the freezing point of water.
Claim 57
Dependent Claim
28 words
Apparatus according to claim 49 including means for converting the kinetic energy of the gas turbine exhaust to pressure and for applying such pressure to the water stream.
Claim 58
Dependent Claim
66 words
Apparatus according to claim 47 wherein the energy directing means includes means for heating a heat transfer fluid, duct means for directing heat transfer fluid from the heating means to a plurality of discrete areas associated with the hull exterior surfaces, and means cooperating with each discrete area operable to implement transfer of heat from heat transfer fluid directed thereto to the exterior of the hull.
Claim 59
Dependent Claim
21 words
Apparatus according to claim 52 including means for selecting the rate at which heat flux is directed to each discrete area.
Claim 60
Dependent Claim
35 words
Apparatus according to claim 52 wherein the hull has a substantially flat bottom which comprises one of said discrete areas, and means for circulating heat transfer fluid between said one area and the heating means.
Claim 61
Dependent Claim
36 words
Apparatus according to claim 54 wherein the heat transfer implementation means associated with the hull bottom comprises a tank adapted for circulation of heat transfer fluid therethrough and of which the hull bottom constitutes a boundary.
Claim 62
Dependent Claim
43 words
Apparatus according to claim 54 wherein the heat transfer implementation means associated with the hull bottom comprises heat exchange coil means for circulation of heat transfer fluid therethrough and disposed in intimate heat transfer relation to the inner surface of the hull bottom.
Claim 63
Dependent Claim
34 words
Apparatus according to claim 56 including means for chilling heat transfer fluid to below ambient temperature externally adjacent the hull bottom and for circulating chilled heat transfer fluid through the heat exchange coil means.
Claim 64
Dependent Claim
31 words
Apparatus according to claim 54 wherein the hull has side wall surfaces above said bottom, selected portions of the hull side wall surfaces corresponding to different ones of said discrete areas.
Claim 65
Dependent Claim
24 words
Apparatus according to claim 58 including means for circulating heat transfer fluid from each of the different discrete areas to the heat exchange device.
Claim 66
Dependent Claim
43 words
Apparatus according to claim 59 wherein the heat transfer implementation means associated with each of the different discrete areas includes a separate tank adapted for circulation of heat transfer fluid therethrough and of which the corresponding hull side wall portion constitutes a boundary.
Claim 67
Dependent Claim
20 words
Apparatus according to claim 60 including means for stimulating circulation of heat transfer fluid within each hull side wall tank.
Claim 68
Dependent Claim
54 words
Apparatus according to claim 59 wherein the heat transfer implementation means associated with each one of the different discrete areas comprises heat exchange coil means adapted for circulation of heat transfer fluid therethrough and disposed in intimate heat transfer relation to the inner surfaces of the corresponding selected portion of the hull side walls.
Claim 69
Dependent Claim
37 words
Apparatus according to claim 58 wherein the heat transfer implementation means associated with at least one of said differenT discrete areas includes nozzle means for discharging heat transfer fluid supplied thereto to the exterior of the hull.
Claim 70
Dependent Claim
55 words
Apparatus according to claim 63 wherein the nozzle means comprises a plurality of nozzles mounted to the hull side wall at different elevations above the hull bottom for discharging heat transfer fluid supplied thereto to the exterior of the hull, and means for regulating the heat flux transfer from the hull at the different elevations.
Claim 71
Dependent Claim
33 words
Apparatus according to claim 63 wherein the heat transfer fluid is water, and the heat transfer means includes means for supplying water from externally of the platform assembly to the heat exchange device.
Claim 72
Dependent Claim
31 words
Apparatus according to claim 52 wherein the heating means includes means for using at least a portion of the exhaust of an internal combustion prime mover as a heat transfer fluid.
Claim 73
Dependent Claim
27 words
Apparatus according to claim 66 wherein the heat transfer fluid includes water, and the means for mixing said portion of exhaust with water for heating the water.
Claim 74
Dependent Claim
50 words
Apparatus according to claim 67 wherein the heat transfer implementation means associated with at least one of said discrete areas includes nozzle means for discharging heat transfer fluid supplied thereto to the exterior of the hull, and wherein the means for mixing said exhaust and water includes the nozzle means.
Claim 75
Dependent Claim
27 words
Apparatus according to claim 68 including pump means for supplying water from externally of the hull to the nozzle means at a pressure greater than ambient pressure.
Claim 76
Dependent Claim
59 words
Apparatus according to claim 69 wherein the prime mover comprises a gas turbine having an exhaust at high temperature and velocity at substantially atmospheric pressure when operated, and means for converting a portion of the turbine exhaust kinetic energy to pressure energy wherein the exhaust pressure is substantially equal to the pressure of water supplied to the nozzle means.
Claim 77
Dependent Claim
33 words
Apparatus according to claim 70 including means for supplying air at substantially ambient temperature to the nozzle means at a pressure substantially equal to the pressure of water supplied to the nozzle means.
Claim 78
Dependent Claim
24 words
Apparatus according to claim 71 wherein the air supplying means includes a duct connected to the gas turbine in association with the compressor thereof.
Claim 79
Dependent Claim
32 words
Apparatus according to claim 69 wherein the prime mover comprises a gas turbine, and including a blower coupled to supply both turbine exhaust and air at ambient temperature to the nozzle means.
Claim 80
Dependent Claim
39 words
Apparatus according to claim 73 including air skirt means for connection circumferentially to the hull, and means for coupling the discharge of the blower to the air skirt means for supporting the platform assembly on a cushion of air.
Claim 81
Dependent Claim
72 words
Apparatus according to claim 74 including means operable for varying the coupling of the blower from the nozzle means to the air skirt means, and means operable for regulating the temperature of the blower discharge from a temperature above the freezing point of water when the blower and nozzle means are coupled to a temperature below but approaching the freezing point of water when the blower and air skirt means are coupled.
Claim 82
Dependent Claim
72 words
Apparatus according to claim 49 including an operations facility carried by the hull for producing oil from a completed oil well, the facility including means for separating combustible gas from oil derived from the well, and the energy directing means includes means for releasing at least a portion of the latent heat of combustion of said gas and for applying at least a portion of the released heat to said hull surroundings.
Claim 83
Dependent Claim
30 words
Apparatus according to claim 76 wherein the latent heat releasing and applying means includes a gas-fired water heater and means for controllably discharging heated water to externally of the hull.
Claim 84
Dependent Claim
27 words
Apparatus according to claim 77 wherein the water discharging means includes a plurality of water discharge nozzles mounted in the hull for discharging water through the hull.
Claim 85
Dependent Claim
48 words
Apparatus accorDing to claim 78 wherein different portions of the hull exterior surfaces correspond to discrete heat transfer areas, at least one water discharge nozzle is associated with each discrete area, and means for regulating the quantity of water supplied from the heater to the several discrete areas.
Claim 86
Dependent Claim
48 words
Apparatus according to claim 79 wherein some of said discrete areas have associated therewith a plurality of water discharge nozzles disposed at different elevations in the hull, and means for regulating the volume rate of water discharge from the nozzles at different elevations within each such discrete area.
Claim 87
Dependent Claim
120 words
Apparatus for performing operations at and in association with an oil or gas well in arctic areas comprising: a. a platform assembly including a buoyant hull having a substantially flat bottom and configured and arranged to float with shallow draft, b. an operations facility carried by the platform assembly operable to perform desired operations at and in association with an oil or gas well, c. heat transfer means carried by the platform assembly in cooperation with the hull exterior surfaces operable for transferring heat energy through selected portions of the hull which are submerged when the hull is afloat, and d. means operable for supporting the platform assembly on a cushion of air above a water, solid or semi-solid surface.
Claim 88
Dependent Claim
120 words
Apparatus for performing operations at and in association with an oil or gas well in arctic areas comprising: a. a platform assembly including a buoyant hull having a substantially flat bottom and configured and arranged to float with shallow draft, b. an operations facility carried by the platform assembly operable to perform desired operations at and in association with an oil or gas well, c. heat transfer means carried by the platform assembly in cooperation with the hull exterior surfaces operable for transferring heat energy through selected portions of the hull which are submerged when the hull is afloat, and d. means operable for supporting the platform assembly on a cushion of air above a water, solid or semi-solid surface.
Claim 89
Dependent Claim
33 words
Apparatus according to claim 81 wherein the air cushion support means includes an air cushion skirt assembly, and means for removably connecting the skirt assembly to the platform assembly circumferentially of the hull.
Claim 90
Dependent Claim
59 words
Apparatus according to claim 82 including means in the platform assembly operable for supplying air at greater than atmospheric pressure to within the skirt assembly below the hull, and the heat transfer means includes means for adjusting the temperature of air supplied to within the skirt assembly to a temperature between ambient temperature and the freezing point of water.
Claim 91
Dependent Claim
42 words
Apparatus according to claim 83 wherein ambient temperature is substantially below the freezing point of water, and the air temperature adjusting means is operable to adjust the temperature of supplied air to a temperature approaching but below the freezing point of water.
Claim 92
Dependent Claim
33 words
Apparatus according to claim 84 including a blower, a prime mover having a high temperature gas exhaust when operated, and means for supplying a controllable quantity of prime mover exhaust to the blower.
Claim 93
Dependent Claim
145 words
Apparatus for performing operations at and in association with a submerged oil or gas well in arctic areas comprising: a. a platform assembly including a buoyant hull defining therein a well open to the bottom of the hull, b. an annular heat transfer device adapted for storage in the well; c. means for disposing the heat transfer device in an operative position at least partially below the hull adjacent the well; and d. an operations facility carried by the platform assembly operable to perform desired operations at and in association with an oil or gas well through the annular heat transfer device during periods when the hull floats in a water pool formed in the upper extent of an ice sheet and is the heat transfer device operative to maintain water communication between the water pool and water over which the ice sheet is formed.
Claim 94
Dependent Claim
145 words
Apparatus for performing operations at and in association with a submerged oil or gas well in arctic areas comprising: a. a platform assembly including a buoyant hull defining therein a well open to the bottom of the hull, b. an annular heat transfer device adapted for storage in the well; c. means for disposing the heat transfer device in an operative position at least partially below the hull adjacent the well; and d. an operations facility carried by the platform assembly operable to perform desired operations at and in association with an oil or gas well through the annular heat transfer device during periods when the hull floats in a water pool formed in the upper extent of an ice sheet and is the heat transfer device operative to maintain water communication between the water pool and water over which the ice sheet is formed.
Claim 95
Independent Claim
94 words
A method for maintaining a floating structure in a substantially fixed position in a pool within ice subject to lateral motion irrespective of ice motion, the method comprising the step of: effectively moving the pool laterally in the ice in a direction opposite to the direction of ice motion and at a rate substantially equal to the rate of ice motion by applying thermal energy outwardly from the submerged surfaces of the floating structure to the ice defining a lateral boundary of the pool on a side thereof opposite the direction of ice motion.
Claim 96
Independent Claim
94 words
A method for maintaining a floating structure in a substantially fixed position in a pool within ice subject to lateral motion irrespective of ice motion, the method comprising the step of: effectively moving the pool laterally in the ice in a direction opposite to the direction of ice motion and at a rate substantially equal to the rate of ice motion by applying thermal energy outwardly from the submerged surfaces of the floating structure to the ice defining a lateral boundary of the pool on a side thereof opposite the direction of ice motion.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |