METHOD AND VESSEL FOR LAYING A PIPELINE.

摘要

A method of S-laying a pipeline from a vessel (103) is disclosed. A stinger (104) extends away from an end of the vessel (103) and the pipeline passes over the stinger (104) as it is laid from the vessel (103). The inclination of the pipeline to the horizontal increases as it passes along the stinger (104) and after it leaves the stinger (104) until it reaches an inflection point beyond the end of the stinger (104) at which the inclination of the pipeline to the horizontal is at a maximum. The inclination of the pipeline thereafter reduces until it touches down on the seabed. The method includes providing guides on the stinger (104) that limit lateral movement of the pipeline relative to the stinger (104) and moving the vessel (103) and the stinger (104) during S-laying to an orientation in which the longitudinal axis of the stinger (104) is inclined to the path of the pipeline (101) just laid on the seabed. The step of moving the vessel (103) and the stinger (104) comprises rotating the vessel (103) and the stinger (104) about a vertical axis passing through or adjacent to the inflection point.