| 摘要 |
A method of abandoning a pipeline during subsea pipelaying from a pipelay vessel (28) comprises suspending the pipe string (38) from a tendon element (36) of an abandonment string and engaging further tendon elements (36) to an upper end of the abandonment string while lowering the pipe string (38) to a handover depth. At the handover depth, tension is applied via a wire (48) to the top of the pipe string (38) at an acute angle to the launch axis. This deflects the pipe string (38) from the launch axis into axial alignment with the wire (48) to transfer the weight load of the pipe string (38) to the wire (48), whereupon the abandonment string can be decoupled from the pipe string (38). Recovery of the pipeline from the seabed can be effected by a reverse process. |
