Abstract:
A device and a method for lowering or raising the end of an undersea pipe between a vessel and the sea bottom by a carriage moving along an inclined J-lay tower and co-operating with chain-locking devices connecting the top end of the pipe to a storage area by passing over a deflector sheave secured to said carriage. A first chain-locking device is secured to said carriage and serves to lock the abandonment chain while lowering said carriage and said top end of the pipe at the end of the chain, said second locking device then being in an open position at the base of said tower. Thereafter, said abandonment chain is locked at the low portion of the tower with the help of said second chain-locking device, with the first chain-locking device being in the open position while the carriage is being raised.
Abstract:
A multipurpose deepwater vessel equipped with a floating structure having a bow, a stern, a weather deck, a first board, and a second board; a J-lay tower hinged to the floating structure along the second board, and movable about a first axis into a number of work positions to join pipe assemblies into an underwater pipeline, and to lay an underwater pipeline; a heavy-duty crane connected at the bow to the floating structure to rotate about a second axis, and having a boom defining an operating range within which the J-lay tower is located in any one of its work positions; and a preassembly line, below the weather deck, for joining pipes into pipe assemblies for supply to the J-lay tower.
Abstract:
A method of transferring pipes from a carrier vessel to a laying vessel includes gripping the pipes in the hold of the carrier vessel and releasing the pipes, in a given position, inside a transfer station on the carrier vessel by means of a manipulator mounted on the carrier vessel. The method also includes guiding a gripping device, connected to a crane, into said given position at the transfer station.
Abstract:
A method of transferring pipes from a carrier vessel to a laying vessel includes gripping the pipes in the hold of the carrier vessel and releasing the pipes, in a given position, inside a transfer station on the carrier vessel by means of a manipulator mounted on the carrier vessel. The method also includes guiding a gripping device, connected to a crane, into said given position at the transfer station.
Abstract:
A device and a method for lowering or raising the end of an undersea pipe between a vessel and the sea bottom by a carriage moving along an inclined J-lay tower and co-operating with chain-locking devices connecting the top end of the pipe to a storage area by passing over a deflector sheave secured to said carriage. A first chain-locking device is secured to the carriage and serves to lock the abandonment chain while lowering the carriage and the top end of the pipe at the end of the chain, a second locking device then being in an open position at the base of the tower. Thereafter, the abandonment chain is locked at the low portion of the tower with the help of the second chain-locking device, with the first chain-locking device being in the open position while the carriage is being raised.
Abstract:
A method of abandoning an underwater pipeline on the bed of a body of water from a laying vessel includes the steps of lowering the free end of the pipeline into the body of water and onto the bed of the body of water using a first and second rope, both connected to the free end of the pipeline and extending from the laying vessel to the free end of the pipeline. The method also includes disconnecting the first rope from the free end of the pipeline, once the free end of the pipeline is laid on the bed of the body of water; and rewinding the first rope onto the laying vessel, while the second rope is still connected to the free end of the pipeline.
Abstract:
A method of abandoning an underwater pipeline on the bed of a body of water from a laying vessel includes the steps of lowering the free end of the pipeline into the body of water and onto the bed of the body of water using a first and second rope, both connected to the free end of the pipeline and extending from the laying vessel to the free end of the pipeline. The method also includes disconnecting the first rope from the free end of the pipeline, once the free end of the pipeline is laid on the bed of the body of water; and rewinding the first rope onto the laying vessel, while the second rope is still connected to the free end of the pipeline.
Abstract:
A multipurpose deepwater vessel equipped with a floating structure having a bow, a stern, a weather deck, a first board, and a second board; a J-lay tower hinged to the floating structure along the second board, and movable about a first axis into a number of work positions to join pipe assemblies into an underwater pipeline, and to lay an underwater pipeline; a heavy-duty crane connected at the bow to the floating structure to rotate about a second axis, and having a boom defining an operating range within which the J-lay tower is located in any one of its work positions; and a preassembly line, below the weather deck, for joining pipes into pipe assemblies for supply to the J-lay tower.