A method of lowering a discrete load from a pipelay vessel comprises holding a rigid rod on an upright launch axis where the rod extends through a hold-back system; coupling a lower end of the rod to the load; connecting a wire to the load either directly or indirectly via the rod; operating the hold-back system to advance the rod downwardly, hence submerging the load, while the weight of the load is suspended from the hold-back system via the rod; when the load is under mater and beneath the splash zone, transferring the weight of the load directly or indirectly from the hold-back system to the wire; and continuing to lower the load in the water, suspended directly or indirectly from the wire. The method may be reversed to recover a load from a subsea location, such as when lifting a wellhead or blowout preventer from the seabed.
Handling loads in subsea operations
2023-12-19
Patent
Electronic Resource
English