Jack-up type offshore platform apparatus

Claim 2

Jack-up type offshore platform apparatus comprising a floatable upper platform, at least one horizontal lower support platform structure nestably arranged in substantially surrounding relation with respect to at least a portion of said upper platform and for disposition in vertically spaced tandem relation below said upper platform when said apparatus is in erected condition, each of said lower support platform structures being of substantially open latticework construction and carrying an attached plurality of upwardly projecting, elongated upper support legs in laterally spaced apart relation to each other and respectively engaging the platform structure thereabove for vertical movement with respect thereto, means for attaching each of said upper support legs at locations along their respective lengths to said platform structure which it engages for vertical movement, said upper platform being mounted for vertical movement on, and having means for its attachment to said upper support legs on that lower support platform structure which is disposed immediately below said upper platform when said apparatus is in said erected condition, a plurality of elongated lower support legs respectively mounted in laterally spaced apart relation to each other on the lowermost of said lower support platform structures for vertical movement independently of each other to project downwardly from the platform when said apparatus is in said erected condition, and means for attaching each of said lower support legs at locations along their respective lengths to said lowermost support platform structure, whereby when said apparatus is in said erected condition, each said lower support platform structure supports and transmits to the support legs therebelow all of the weight of the structure thereabove.

Claim 3

Jack-up type offshore platform apparatus according to claim 1 wherein each of said lower support legs has a buoyancy tank attached to the lower end thereof for rendering the leg at least partially buoyant, and wherein said apparatus further comprises winch and cable means operable from said upper platform for raising and lowering at least said lower support legs with respect to said lowermost lower supPort platform structure.

Claim 4

Jack-up type offshore platform apparatus according to claim 2 wherein each of said lower support platform structures has buoyancy tank means rendering the structure at least partially buoyant, and said winch and cable means is further attachable to each of said upper suport legs for raising and lowering their associated lower support platform structure with respect to said upper platform.

Claim 5

Jack-up type offshore platform apparatus according to claim 2 wherein said winch and cable means includes pulley means temporarily mounted atop said upper support legs on which said upper platform is mounted for vertical movement.

Claim 6

Jack-up type offshore platform apparatus according to claim 2 wherein each of said lower support legs further has a buoyancy tank attached near the upper end thereof.

Claim 7

Jack-up type offshore platform apparatus according to claim 1 wherein said lateral spacing apart of the legs of each of said pluralities of upper and lower support legs is greater than that of any of said pluralities of legs thereabove when said apparatus is in said erected condition.

Claim 8

Jack-up type offshore platform apparatus according to claim 6 wherein each of said lower support legs has a buoyancy tank attached thereto for rendering the leg only partially buoyant, and wherein said apparatus further comprises respective low-powered jacks on the lowermost of said lower support platform structures and engaging each of said lower support legs for raising and lowering the same with respect to said lowermost support platform structure, each of said low-powered jacks having power sufficient to raise its said associated lower support leg only when the leg is rendered partially buoyant by its said attached buoyancy tank.

Claim 9

Jack-up type offshore platform apparatus according to claim 6 which further comrises respective high-powered jacks on said lowermost lower support platform structure, and engaging each of said lower support legs, each of said jacks being operable independently of each other for raising and lowering each of said lower support legs with respect to said lowermost support platform structure to position and set the support legs on a sea bottom, and said jacks being operable concurrently for raising and lowering said lowermost support platform structure on said lower support legs when the same are set on said sea bottom to commensurately raise and lower all of said apparatus thereabove.

Claim 10

Jack-up type offshore platform apparatus according to claim 1 wherein each of said upper and lower support legs is at least 250 feet long.

Claim 11

Jack-up type offshore platform apparatus according to claim 1 wherein at least the lower end portion of the length of each of said lower support legs has elongated cylindrical shape, and said apparatus further comprises a floodable buoyancy tank on said lower end of each of said lower support legs, a plurality of annularly spaced apart, tubular pile guides extending vertically through each of said buoyancy tanks, a corresponding plurality of vertically extending pile driver guides attached to the interior of each of said lower end portions and respectively in vertical alignment with said pile guides, and removable pile driver means suspended substantially from said upper platform and positionable within each of said support leg lower end portions for engaging each of said respective pile driver guides for driving a pile positioned within its said associated pile guide, each of said tubular pile guides having plate means attached substantially adjacent to its lower end and providing a constricted opening for supporting a pile within the guide, said plate means being rupturable by said pile when the latter is driven.

Claim 12

Jack-up type offshore platform apparatus according to claim 1 wherein each of said lower support platform structures has buoyancy tank means rendering the structure at least partially buoyant.

Claim 13

Jack-up type offshore platform apparatus comprising a floatable upper platform, at least one horizontal lower support platform structure nestably arranged with respect to said upper platform for disposition in vertically spaced tandem relation below the latter when said apparatus is in erected condition, each of said lower support platform structures carrying an attached plurality of upwardly projecting, elongated upper support legs in laterally spaced apart relation to each other and respectively engaging the platform structure thereabove for vertical movement with respect thereto, means for attaching each of said upper support legs at locations along their respective lengths to said platform structure which it engages for vertical movement, said upper platform being mounted for vertical movement on, and having means for its attachment to said upper support legs on that lower support platform structure which is disposed immediately below said upper platform when said apparatus is in said erected condition, a plurality of elongated lower support legs respectively mounted in laterally spaced apart relation to each other on the lowermost of said lower support platform structures for vertical movement independently of each other to project downwardly from the platform when said apparatus is in said erected condition, and means for attaching each of said lower support legs at locations along their respective lengths to said lowermost support platform structure, whereby when said apparatus is in said erected condition, each said lower support platform structure supports and transmits to the support legs therebelow all of the weight of the structure thereabove, said lateral spacing apart of the legs of each of said pluralities of upper and lower support legs being greater than that of any of said pluralities of legs thereabove when said apparatus is in said erected condition, at least one of said lower support platform structures having a vertically movable portion associated with each of said attached upper support legs, said upper support legs being respectively attached to said movable portions, and respective connection means between each of said movable portions and the remainder of said one platform structure to provide limited vertical movement of the movable portion from a position above to a position below the elevation of said remainder of the platform structure when said apparatus is in said erected condition.

Claim 14

Jack-up type offshore platform apparatus comprising a floatable upper platform, at least one horizontal lower support platform structure nestably arranged with respect to said upper platform for disposition in vertically spaced tandem relation below the latter when said apparatus is in erected condition, each of said lower support platform structures carrying an attached plurality of upwardly projecting, elongated upper support legs in laterally spaced apart relation to each other and respectively engaging the platform structure thereabove for vertical movement with respect thereto, means for attaching each of said upper support legs at locations along their respective lengths to said platform structure which it engages for vertical movement, said upper platform being mounted for vertical movement on, and having means for its attachment to said upper support legs on that lower support platform structure which is disposed immediately below said upper platform when said apparatus is in said erected condition, a plurality of elongated lower support legs respectively mounted in laterally spaced apart relation to each other on the lowermost of said lower support platform structures for vertical movement independently of each other to project downwardly from the platform when said apparatus is in said erected condition, and means for attaching each of said lower support legs at locations along their respective lengths to said lowermost support platform structure, whereby when said apparatus is in said erected condition, each said lower support platform structure supports and transmits to the support legs therebelow all of the weight of the structure thereabove, said lateral spacing apart of the legs of each of said pluralities of upper and lower support legs being greater than that of any of said pluralities of legs thereabove when said apparatus is in said erected condition, at least one of said lower support platform structures having a vertically movable portion associated with each of said attached upper support legs, said upper support legs being respectively attached to said movable portions, and respective connection means between each of said movable portions and the remainder of said one platform structure to provide limited vertical movement of the movable portion from a position above to a position below the elevation of said remainder of the platform structure when said apparatus is in said erected condition.

Claim 15

Jack-up type offshore platform apparatus according to claim 12 wherein said other support legs which engage said one platform structure for vertical movement with respect thereto respectively engage said movable portions of the platform structure.

Claim 16

Jack-up type offshore platform apparatus according to claim 13 wherein each of said movable portions has a pair of buoyancy tanks, one of said pair of buoyancy tanks being floodable.

Claim 17

Jack-up type offshore platform apparatus comprising a floatable upper platform, at least one horizontal lower support platform structure nestably arranged with respect to said upper platform for disposition in vertically spaced tandem relation below the latter when said apparatus is in erected condition, each of said lower support platform structures carrying an attached plurality of upwardly projecting, elongated upper support legs in laterally spaced apart relation to each other and respectively engaging the platform structure thereabove for vertical movement with respect thereto, means for attaching each of said upper support legs at locations along their respective lengths to said platform structure which it engages for vertical movement, said upper platform being mounted for vertical movement on, and having means for its attachment to said upper support legs on that lower support platform structure which is disposed immediately below said upper platform when said apparatus is in said erected condition, a plurality of elongated lower support legs respectively mounted in laterally spaced apart relation to each other on the lowermost of said lower support platform structures for vertical movement independeNtly of each other to project downwardly from the platform when said apparatus is in said erected condition, and means for attaching each of said lower support legs at locations along their respective lengths to said lowermost support platform structure, whereby when said apparatus is in said erected condition, each said lower support platform structure supports and transmits to the support legs therebelow all of the weight of the structure thereabove, each of said lower support legs comprising an independently operated, fluid-powered jack for adjusting its length independently of any other support leg, each of said fluid powered jacks comprising a pair of elongated, substantially empty upper and lower cylinders concentrically arranged for telescoping slidable movement relative to each other and together constituting at least a portion of the length of said associated support leg, said upper cylinder having a closed upper end and an open lower end, and said lower cylinder having a closed lower end and an open upper end, means for introducing fluid under pressure into, and for discharging the same from the interior of said cylinders for inducing said telescoping slidable movement relative to each other, means for admitting and discharging sea water into and from said interior of said cylinders, and means for locking said upper and lower cylinders together at positions along the length of their said relative movement.

Claim 18

Jack-up type offshore platform apparatus comprising a floatable upper platform, at least one horizontal lower support platform structure nestably arranged with respect to said upper platform for disposition in vertically spaced tandem relation below the latter when said apparatus is in erected condition, each of said lower support platform structures carrying an attached plurality of upwardly projecting, elongated upper support legs in laterally spaced apart relation to each other and respectively engaging the platform structure thereabove for vertical movement with respect thereto, means for attaching each of said upper support legs at locations along their respective lengths to said platform structure which it engages for vertical movement, said upper platform being mounted for vertical movement on, and having means for its attachment to said upper support legs on that lower support platform structure which is disposed immediately below said upper platform when said apparatus is in said erected condition, a plurality of elongated lower support legs respectively mounted in laterally spaced apart relation to each other on the lowermost of said lower support platform structures for vertical movement independeNtly of each other to project downwardly from the platform when said apparatus is in said erected condition, and means for attaching each of said lower support legs at locations along their respective lengths to said lowermost support platform structure, whereby when said apparatus is in said erected condition, each said lower support platform structure supports and transmits to the support legs therebelow all of the weight of the structure thereabove, each of said lower support legs comprising an independently operated, fluid-powered jack for adjusting its length independently of any other support leg, each of said fluid powered jacks comprising a pair of elongated, substantially empty upper and lower cylinders concentrically arranged for telescoping slidable movement relative to each other and together constituting at least a portion of the length of said associated support leg, said upper cylinder having a closed upper end and an open lower end, and said lower cylinder having a closed lower end and an open upper end, means for introducing fluid under pressure into, and for discharging the same from the interior of said cylinders for inducing said telescoping slidable movement relative to each other, means for admitting and discharging sea water into and from said interior of said cylinders, and means for locking said upper and lower cylinders together at positions along the length of their said relative movement.

Claim 19

Jack-up type offshore platform apparatus according to claim 15 wherein said upper and lower cylinders constitute substantially the lower half of the length of said associated support leg.

Claim 20

Jack-up type offshore platform apparatus according to claim 16 wherein said means for admitting and discharging sea water into and from said interior spacing between said cylinders comprises means providing a valved opening near the lower end of said lower cylinder.

Claim 21

Jack-up type offshore platform apparatus according to claim 16 wherein each of said lower cylinders has a buoyancy tank adjacent to its lower end, said valved opening being disposed for admitting and discharging sea water at a location above said buoyancy tank.

Claim 22

Jack-up type offshore platform apparatus according to claim 15 wherein the length of each of said lower support legs is at least 250 feet, and the lenghts of each of said cylinders is at least 40 feet.

Claim 23

Jack-up type offshore platform apparatus according to claim 15 wherein said fluid under pressure is compressed air.

Claim 24

Jack-up type offshore platform apparatus according to claim 15 wherein said fluid under pressure is compressed gas, and said means for introducing said gas comprises compressed gas tanks mounted on said upper platform.

Claim 25

Jack-up type offshore platform apparatus according to claim 15 wherein said means for locking said upper and lower cylinders together comprises ratchet pawl means mounted on one of said cylinders for movement towards and away from the other of said cylinders, ratchet pin means mounted on said other cylinder for engagement by said ratchet pawl means of the first said cylinder to prevent said telescoping movement between said upper and lower cylinders in one direction, radially movable means on one of said cylinders, and stop means on the other of said cylinders for engagement by said radially movable means to prevent said telescoping movement between said upper and lower cylinders in the opposite direction.

Claim 26

Jack-up type offshore platform apparatus according to claim 22 wherein said means for locking said upper and lower cylinders together further comprises latch means spaced upwardly from the lower end of said lower cylinder for locking said cylinders in their fully telescoped relation.

Claim 27

A support leg for a jack-up type offshore platform apparatus, said leg comprising a pair of elongated, substantially empty upper and lower cylinders concentrically arranged for telescoping slidable movement relative to each other and together constituting at least a portion of tHe length of said support leg, said upper cylinder having a closed upper end and an open lower end, and said lower cylinder having a closed lower end and an open upper end, means for introducing fluid under pressure into, and for discharging the same from the interior of said cylinders for inducing said telescoping slidable movement relative to each other, means for admitting and discharging sea water into and from said interior of said cylinders, and means for locking said upper and lower cylinders together at positions along the length of their said relative movement.

Claim 28

A support leg for a jack-up type offshore platform apparatus, said leg comprising a pair of elongated, substantially empty upper and lower cylinders concentrically arranged for telescoping slidable movement relative to each other and together constituting at least a portion of tHe length of said support leg, said upper cylinder having a closed upper end and an open lower end, and said lower cylinder having a closed lower end and an open upper end, means for introducing fluid under pressure into, and for discharging the same from the interior of said cylinders for inducing said telescoping slidable movement relative to each other, means for admitting and discharging sea water into and from said interior of said cylinders, and means for locking said upper and lower cylinders together at positions along the length of their said relative movement.

Claim 29

A support leg according to claim 24 wherein said upper and lower cylinders substantially constitute the lower length portion of said support leg, and said support leg has an upper length portion having wave-transparent construction.

Claim 30

A support leg according to claim 25 which further comprises a buoyancy tank within said lower length portion.

Claim 31

A support leg according to claim 26 wherein said buoyancy tank forms said closed lower end of said lower cylinder, and which further comprises an inverted-dish shaped footing at the underside of said buoyancy tank, and water jet means for relieving suction forces adjacent to said footing as would otherwise resist the raising of said support leg when resting on a sea bottom.

Claim 32

Jack-up type, mobile offshore platform apparatus comprising a floatable upper platform, a first plurality of elongated, substantially vertical upper support legs mounted in laterally spaced apart relation to each other on said upper platform for vertical movement with respect thereto, a horizontal lower support platform structure extending laterally between, and rigidly attached to the lower ends of all of said first plurality of legs, and having buoyancy tank means rendering the platform structure and said upper support legs at least partially buoyant, means on said upper platform for jacking the platform upwardly and downwardly along the lengths of said upper support legs and for attaching the platform to each of said legs at locations along their respective lengths, a plurality of elongated, substantially vertical lower support legs respectively mounted in laterally spaced apart relation to each other on said lower support platform structure for vertical movement with respect thereto independently of each other and independently of said upper platform, a buoyancy tank on the lower end of each of said lower support legs for rendering the same at least partially buoyant, winch and cable means operable from said upper platform and including removable pulley means mounted substantially adjacent to the tops of said upper support legs for raising and lowering said lower support legs with respect to said lower support platform structure, and means for attaching each of said lower support legs to said lower support platform structure at locations along their respective lengths, said upper and lower support legs and said lower support platform having substantially wave-transparent construction, and said lateral spaced apart relation of said lower support legs being wider than that of said upper support legs.

Claim 33

Jack-up type, mobile offshore platform apparatus comprising a floatable upper platform, a first plurality of elongated, substantially vertical upper support legs mounted in laterally spaced apart relation to each other on said upper platform for vertical movement with respect thereto, a horizontal lower support platform structure extending laterally between, and rigidly attached to the lower ends of all of said first plurality of legs, and having buoyancy tank means rendering the platform structure and said upper support legs at least partially buoyant, means on said upper platform for jacking the platform upwardly and downwardly along the lengths of said upper support legs and for attaching the platform to each of said legs at locations along their respective lengths, a plurality of elongated, substantially vertical lower support legs respectively mounted in laterally spaced apart relation to each other on said lower support platform structure for vertical movement with respect thereto independently of each other and independently of said upper platform, a buoyancy tank on the lower end of each of said lower support legs for rendering the same at least partially buoyant, winch and cable means operable from said upper platform and including removable pulley means mounted substantially adjacent to the tops of said upper support legs for raising and lowering said lower support legs with respect to said lower support platform structure, and means for attaching each of said lower support legs to said lower support platform structure at locations along their respective lengths, said upper and lower support legs and said lower support platform having substantially wave-transparent construction, and said lateral spaced apart relation of said lower support legs being wider than that of said upper support legs.

Claim 34

Jack-up type offshore platform apparatus comprising a floatable upper platform, a plurality of elongated support legs in laterally spaced apart relation to each other and respectively engaging said upper platform for vertical slidable movement with respect thereto, each of said support legs being at least 250 feet long and having an upper length portion and a lower length portion, said lower length portion of each leg being formed by a pair of substantially empty upper and lower cylinders arranged in telescoping slidable relation with each other, said upper cylinder of each leg being at least 40 feet long and having a closed upper end and an open lower end, and said lower cylinder of each leg being at least 40 feet long and having an open upper end and a buoyancy tank on and closing its lower end, means on each said support leg for introducing fluid under presSure into, and for discharging the same from the interior of its said cylinders for inducing said telescoping slidable movement relative to each other and independently of such movement of said cylinders on any other of said support legs, means on each of said lower cylinders for admitting and discharging sea water into and from the interior thereof, and means for locking together each of said pairs of upper and lower cylinders, respectively, at locations along the lengths of their said relative movement, a horizontal lower support platform structure attached to and extending between said lower ends of all of said upper cylinders whereby said support legs project upwardly a uniform height therefrom, and means for attaching said upper platform to said upper length portions of said support legs.

Claim 35

Jack-up type offshore platform apparatus comprising a floatable upper platform, a plurality of elongated support legs in laterally spaced apart relation to each other and respectively engaging said upper platform for vertical slidable movement with respect thereto, each of said support legs being at least 250 feet long and having an upper length portion and a lower length portion, said lower length portion of each leg being formed by a pair of substantially empty upper and lower cylinders arranged in telescoping slidable relation with each other, said upper cylinder of each leg being at least 40 feet long and having a closed upper end and an open lower end, and said lower cylinder of each leg being at least 40 feet long and having an open upper end and a buoyancy tank on and closing its lower end, means on each said support leg for introducing fluid under presSure into, and for discharging the same from the interior of its said cylinders for inducing said telescoping slidable movement relative to each other and independently of such movement of said cylinders on any other of said support legs, means on each of said lower cylinders for admitting and discharging sea water into and from the interior thereof, and means for locking together each of said pairs of upper and lower cylinders, respectively, at locations along the lengths of their said relative movement, a horizontal lower support platform structure attached to and extending between said lower ends of all of said upper cylinders whereby said support legs project upwardly a uniform height therefrom, and means for attaching said upper platform to said upper length portions of said support legs.

Claim 36

Jack-up type offshore platform apparatus according to claim 29 wherein said lower support platform structure and said upper length portions of said support legs have wave-transparent construction, and which further comprises jack means on said upper platform for jacking of the platform upwardly and downwardly along the lengths of said support leg upper length portions.