Patent ID: 11927060
Assignee: ITREC B.V.
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 11:
12. A method for drilling a subsea wellbore, comprising the step of using an offshore vessel comprising a drilling tower and an associated firing line,
the vessel further comprising:
a crown block supported by the drilling tower;
a traveling block adapted to suspend a tubulars string therefrom along the firing line;
a hoisting system with a first hoisting device comprising a first hoisting winch and a first hoisting cable connected to said first hoisting winch, wherein the traveling block is suspended from the crown block by the first hoisting cable;
a roughneck device for connecting and disconnecting tubulars in assembly and disassembly of a tubulars string in the firing line, the roughneck device being vertically movable relative to the drilling tower;

a tubulars handling device, wherein the tubulars handling device is adapted to grip and retain a tubular and to move said tubular between a remote position and a position in the firing line, and wherein the tubulars handling device is configured to vertically move a gripped and retained tubular between a lower position and a raised position in the firing line;
a working deck that is vertically moveable relative to the drilling tower; and
a slip device that is mounted to the working deck and that is adapted to suspend the tubulars string therefrom in the firing line when the slip device is engaged with the tubulars string,
wherein the hoisting system further comprises a second hoisting device comprising a second hoisting winch, a second hoisting cable connected to said second hoisting winch, and a connector suspended by the second hoisting cable from the crown block, wherein the connector is adapted to be selectively connected to one of the working deck and the traveling block, and
wherein the hoisting system provides a first configuration and a second configuration, wherein, when the hoisting system is in the first configuration, the connector is connected to the working deck such that the working deck is raised and lowered by the second hoisting device and the traveling block is raised and lowered by the first hoisting device, and wherein, when the hoisting system is in the second configuration, the connector is connected to the traveling block such that the traveling block is suspended by both the first and second hoisting cables so that a tubulars string suspended from the traveling block is to be raised and lowered by both the first and second winches.