Holding Back Elongate Elements During Subsea Operations
AssigneeAcergy France SAS
InventorsOlivier Lodeho, Johan Janot, Vincent Loentgen
Life of this patent
Estimating the term…
Abstract
A subsea pipeline coated with a thermally insulating coating has a radially outer surface shaped to define external hold-back formations. In a J-lay operation, the weight load of a pipeline catenary is held back using a complementary bushing or clamp of an installation vessel engaged with the hold-back formations. The weight load is transferred from the catenary to the bushing or clamp by shear forces acting through the coating. The coating extends continuously along the pipe and is interposed between the hold-back formations and the underlying pipe. The hold-back formations may be integral with the coating.
Claims30
A pipe joint for offshore fabrication and installation of a pipeline in a J-lay operation, the pipe joint comprising:
- a length of pipe;
- a thermally-insulating coating around the length of pipe;
- and
- a radially outer surface shaped to define at least one external radially-projecting hold-back formation configured to facilitate suspending of the pipe joint during the J-lay operation, the or each hold-back formation being a ring that extends continuously around the pipe joint circumferentially;
- wherein the coating extends continuously along the pipe on a radially inner side of the, or each, hold-back formation and is interposed between the, or each, hold-back formation and the pipe.
A hold-back bushing or travelling clamp for use in J-lay operations, the bushing or clamp being annular and having a radially inner surface shaped to engage with one or more external hold-back formations projecting radially from a pipe joint and configured to facilitate suspending of the pipe joint during a J-lay operation, the or each hold-back formation being a ring that extends continuously around the pipe joint circumferentially.
A method of manufacturing a pipe joint for offshore fabrication and installation of a pipeline in a J-lay operation, the method comprising:
- applying a thermally-insulating coating onto a length of pipe;
- and
- forming or attaching one or more external radially-projecting hold-back formations onto the coating, the or each hold-back formation being a ring that extends continuously around the pipe joint circumferentially and being configured to facilitate suspending of the pipe joint during the J-lay operation.
A J-lay method for offshore fabrication and installation of a pipeline, the method comprising:
- attaching a pipe joint to an upper end of a pipe string catenary suspended from an installation vessel, the pipe joint comprising a thermally-insulating coating around a length of pipe, which coating extends continuously along the pipe and is interposed between one or more external radially-projecting hold-back formations and the pipe, the or each hold-back formation being a ring that extends continuously around the pipe joint circumferentially and being configured to facilitate suspending of the pipe joint during a J-lay operation;
- and
- holding back a weight load of the catenary using a bushing or clamp of the vessel engaged with the, or each, hold-back formation.
Dependencies are inferred from the claim text.