Multi-activity offshore exploration and/or development drilling method and apparatus

Claim 2

A drillship having a bow, a stern and an intermediate moon pool between the bow and stern and being fitted to conduct offshore drilling operations through the moon pool and into the bed of a body of water, said drillship including: a derrick positioned upon the drillship and extending above the moon pool for simultaneously supporting drilling operations and operations auxiliary to drilling operations through the moon pool; a first means connected to said derrick for advancing tubular members through the moon pool, to the seabed and into the bed of the body of water; first means, connected to said derrick, for handling tubular members as said tubular members are advanced through the moon pool by said first means for advancing; a second means connected to said derrick for advancing tubular members through the moon pool, to the seabed and into the bed of the body of water; second means, connected to said derrick, for handling tubular members as said tubular members are advanced through the moon pool by said second means for advancing for conducting operations extending to the seabed auxiliary to said drilling operations; and means positioned within said derrick for transferring tubular assemblies between said first means for advancing tubular members and said second means for advancing tubular members to facilitate simultaneous drilling operations and operations auxiliary to said drilling operations, wherein said drilling activity can be conducted from said derrick by said first or second means for advancing and said first or second means for handling tubular members and auxiliary drilling activity can be simultaneously conducted from said derrick by the other of said first or second means for advancing and the other of said first or second means for handling tubular members.

Claim 3

A drillship as defined in claim 1 wherein said first and second means for advancing tubular members comprises: a first and second top drive assembly respectively.

Claim 4

A drillship as defined in claim 1 wherein said first and second means for advancing tubular members comprises: a first and second rotary table positioned within said derrick.

Claim 5

A drillship as defined in claim 1 wherein said means for transferring includes: a rail assembly operably extending between a position adjacent to said first means for advancing tubular members and a position adjacent to said second means for advancing tubular members; said first means for handling tubular members being mounted to traverse upon said rail wherein conduit assemblies may be operably transferred between said first means for advancing tubular members and said second means for advancing tubular members to facilitate simultaneous drilling operations and operations auxiliary to said drilling operations.

Claim 6

A drillship as defined in claim 3 wherein: said first rotary table and said second rotary table being mutually spaced along a center line of the drillship and within the periphery of said derrick.

Claim 7

A drillship as defined in claim 1 and further including: a first driller's console operable to control said first means for advancing tubular members; and a second driller's console substantially similar to said first driller's console and being operable to independently control said second means for advancing tubular members.

Claim 8

A drillship as defined in claim 1 and further including: a first tubular setback envelope positioned adjacent to said first means for advancing tubular members; and a second tubular setback envelope positioned adjacent to said second means for advancing tubular members.

Claim 9

A drillship as defined in claim 7 and further including: a third tubular setback envelope positioned between said first tubular setback envelope and said second tubular setback envelope.

Claim 10

A drillship as defined in claim 7 and further including: a tubular handling system for transferring tubular members between said first tubular setback envelope and said second tubular setback envelope and said first means for advancing tubular members and said second means for advancing tubular members.

Claim 11

A multi-activity drilling assembly operable to be mounted upon a drilling deck of a drillship, semi-submersible, tension leg platform, jack-up-platform, or offshore tower and positioned above the surface of a body of water for supporting drilling operations through the drilling deck, to the seabed and into the bed of the body of water, said multi-activity drilling assembly including: a derrick operable to be positioned above a drilling deck and extending over an opening in the drilling deck for simultaneously supporting drilling operations and operations auxiliary to drilling operations through the drilling deck; a first top drive positioned within the periphery of said derrick; a first drawworks positioned adjacent to said derrick and operably connected to a first traveling block positioned within said derrick adjacent to said top drive for conducting drilling operations on a well through the drilling deck; a second top drive positioned within the periphery of said derrick; a second drawworks positioned adjacent to said derrick and operably connected to a second traveling block positioned within said derrick adjacent to said second top drive for conducting drilling operations or operations auxiliary to said drilling operations extending to the seabed for the well; and means positioned within said drilling derrick for transferring tubular assemblies between a first top drive station and a second top drive station to facilitate simultaneous drilling operations and operations to the seabed auxiliary to said drilling operations, wherein drilling activity can be conducted within said derrick with said first or second top drive, said first or second drawworks and said first or second traveling block and auxiliary drilling activity extending to the seabed can be simultaneously conducted within said derrick with the other of said first or second top drive, the other of said first or second drawworks and the other of said first or second traveling block.

Claim 12

A multi-activity drilling assembly operable to be mounted upon a drilling deck of a drillship, semi-submersible, tension leg platform, jack-up-platform, or offshore tower and positioned above the surface of a body of water for supporting drilling operations through the drilling deck, to the seabed and into the bed of the body of water, said multi-activity drilling assembly including: a derrick operable to be positioned above a drilling deck and extending over an opening in the drilling deck for simultaneously supporting drilling operations and operations auxiliary to drilling operations through the drilling deck; a first top drive positioned within the periphery of said derrick; a first drawworks positioned adjacent to said derrick and operably connected to a first traveling block positioned within said derrick adjacent to said top drive for conducting drilling operations on a well through the drilling deck; a second top drive positioned within the periphery of said derrick; a second drawworks positioned adjacent to said derrick and operably connected to a second traveling block positioned within said derrick adjacent to said second top drive for conducting drilling operations or operations auxiliary to said drilling operations extending to the seabed for the well; and means positioned within said drilling derrick for transferring tubular assemblies between a first top drive station and a second top drive station to facilitate simultaneous drilling operations and operations to the seabed auxiliary to said drilling operations, wherein drilling activity can be conducted within said derrick with said first or second top drive, said first or second drawworks and said first or second traveling block and auxiliary drilling activity extending to the seabed can be simultaneously conducted within said derrick with the other of said first or second top drive, the other of said first or second drawworks and the other of said first or second traveling block.

Claim 13

A multi-activity drilling assembly as defined in claim 10 wherein said means for transferring includes: a rail assembly operably extending between a position adjacent to said first top drive station and a position adjacent to said second top drive station; a first tubular handling apparatus mounted to traverse upon said rail; and a second tubular handling apparatus mounted to traverse upon said rail, wherein tubular assemblies may be operably transferred between said first top drive and said second top drive to facilitate simultaneous drilling operations and operations auxiliary to said drilling operations.

Claim 14

A multi-activity drilling assembly as defined in claim 11 and further including: a first tubular setback envelope positioned adjacent to said first top drive station; and a second tubular setback envelope positioned adjacent to said second top drive station.

Claim 15

A multi-activity drilling assembly as defined in claim 12 and further including: a tubular handling system for transferring tubular assemblies between said first tubular setback envelope and said second tubular setback envelope and said first top drive station and said second top drive station.

Claim 16

A multi-activity drilling assembly as defined in claim 10 wherein said pipe handling system includes: a rail assembly operably extending between a position adjacent to said first top drive station and a position adjacent to said second top drive station; and at least one tubular handling apparatus operable for traveling upon and along said rail assembly.

Claim 19

A method for conducting offshore drilling operations as defined in claim 15 wherein said step of advancing the tubular members from the first tubular station functions includes: rotating the tubular members with a first top drive supported from the derrick.

Claim 20

A method for conducting offshore drilling operations as defined in claim 11 wherein said step of advancing the tubular members from the second tubular stations includes: rotating the tubular members with a second top drive supported from the derrick.

Claim 21

A method for conducting offshore drilling operations as defined in claim 15 wherein said step of advancing tubular members from the second station includes: making up new drilling assemblies with a rotary table and drawworks.

Claim 25

A method for conducting offshore drilling operations as defined in claim 20 wherein said step of advancing the tubular members from the first tubular station functions includes: rotating the tubular members with a first top drive supported from an upright superstructure.

Claim 26

A method for conducting offshore drilling operations as defined in claim 21 wherein said step of advancing the tubular members from the second tubular stations includes: rotating the tubular members with a second top drive supported from an upright superstructure.

Claim 27

A method for conducting offshore drilling operations as defined in claim 20 wherein said step of advancing tubular members from the first second tubular stations includes: rotating tubular members at said first tubular station with a rotary table; and rotating tubular members at said second tubular station with a second rotary table.

Claim 28

A method for conducting drilling operations as defined in claim 20 wherein said steps of advancing first and second tubular members includes: hoisting tubular members from a first tubular station; and hoisting tubular members from a second tubular station respectively.

Claim 29

A multi-activity assembly operable to be positioned above the surface of a body of water for conducting at least one of work over and completion operations from a drilling deck, to the seabed and into the bed of the body of water, said multi-activity assembly including: a superstructure operable to be mounted upon a drilling deck for simultaneously supporting at least one of a work over and completion operation for a well and supporting operations to the seabed auxiliary to said at least one of said work over and completion operations for the well; first means connected to said drilling superstructure for advancing tubular members to the seabed and into a well at the bed of the body of water; second means connected to said superstructure for advancing tubular members, simultaneously with said first means into the body of water to the seabed; and means for transferring tubular members between said first means for advancing tubular members and said second means for advancing tubular members, wherein at least one of said work over and completion activity can be conducted for a well from said superstructure by said first means for advancing tubular members to the seabed and auxiliary activity can be simultaneously conducted to the seabed for the well from said superstructure by said second means for advancing tubular members.

Claim 30

A multi-activity assembly operable to be positioned above the surface of a body of water for conducting at least one of work over and completion operations from a drilling deck, to the seabed and into the bed of the body of water, said multi-activity assembly including: a superstructure operable to be mounted upon a drilling deck for simultaneously supporting at least one of a work over and completion operation for a well and supporting operations to the seabed auxiliary to said at least one of said work over and completion operations for the well; first means connected to said drilling superstructure for advancing tubular members to the seabed and into a well at the bed of the body of water; second means connected to said superstructure for advancing tubular members, simultaneously with said first means into the body of water to the seabed; and means for transferring tubular members between said first means for advancing tubular members and said second means for advancing tubular members, wherein at least one of said work over and completion activity can be conducted for a well from said superstructure by said first means for advancing tubular members to the seabed and auxiliary activity can be simultaneously conducted to the seabed for the well from said superstructure by said second means for advancing tubular members.

Claim 31

A multi-activity assembly operable to be supported from a drilling deck and positioned above the surface of a body of water, as defined in claim 25, wherein said first and second means for advancing tubular members include: a first and second top drive assembly respectively.

Claim 32

A multi-activity assembly operable to be supported from a drilling deck and positioned above the surface of a body of water, as defined in claim 25, wherein said first and second means for advancing tubular members include: a first and second rotary table respectively.

Claim 33

A multi-activity assembly operable to be supported from a drilling deck and positioned above the surface of a body of water, as defined in claim 25, wherein said first and second means for advancing tubular members include: a first and second means for hoisting tubular members respectively.

Claim 36

A multi-activity drilling assembly operable to be supported from a position above the surface of a body of water for conducting drilling operations into the bed of the body of water, said multi-activity drilling assembly including: a drilling superstructure operable to be mounted upon a drilling deck for simultaneously supporting drilling operations for a well and operations auxiliary to drilling operations for the well; first means connected to said drilling superstructure for advancing tubular members into the bed of body of water, wherein said first means includes a first means for hoisting tubular members; second means connected to said drilling superstructure for advancing tubular members simultaneously with said first means into the body of water to the seabed, wherein said second means includes a second means for hoisting tubular members; and means positioned adjacent to said first and second means for advancing tubular members for transferring tubular assemblies between said first means for advancing tubular members and said second means for advancing tubular members to facilitate simultaneous drilling operations auxiliary to said drilling operations, wherein drilling activity can be conducted for the well from said drilling superstructure by said first means for advancing tubular members and auxiliary drilling activity can be simultaneously conducted for the well from said drilling superstructure by said second means for advancing tubular members.

Claim 37

A multi-activity drilling assembly operable to be supported from a position above the surface of a body of water for conducting drilling operations into the bed of the body of water, said multi-activity drilling assembly including: a drilling superstructure operable to be mounted upon a drilling deck for simultaneously supporting drilling operations for a well and operations auxiliary to drilling operations for the well; first means connected to said drilling superstructure for advancing tubular members into the bed of body of water, wherein said first means includes a first means for hoisting tubular members; second means connected to said drilling superstructure for advancing tubular members simultaneously with said first means into the body of water to the seabed, wherein said second means includes a second means for hoisting tubular members; and means positioned adjacent to said first and second means for advancing tubular members for transferring tubular assemblies between said first means for advancing tubular members and said second means for advancing tubular members to facilitate simultaneous drilling operations auxiliary to said drilling operations, wherein drilling activity can be conducted for the well from said drilling superstructure by said first means for advancing tubular members and auxiliary drilling activity can be simultaneously conducted for the well from said drilling superstructure by said second means for advancing tubular members.