| 摘要 |
A method of abandoning a pipeline during subsea pipelaying comprises suspending the pipe string from a tendon element of an abandonment string and engaging further tendon elements to an upper end of the abandonment string while lowering the pipe string to a handover depth. A tendon element comprises a tensile load-bearing member extending between end connector formations and at least one sleeve removably mounted around the load bearing member. At the handover depth, tension is applied via a wire to the top of the pipe string at an acute angle to the launch axis. This deflects the pipe string from the launch axis into axial alignment with the wire to transfer the weight load of the pipe string to the wire, whereupon the abandonment string can be decoupled from the pipe string. Recovery of the pipeline from the seabed can be effected by a reverse process. |
