Marine pipelaying system and method

摘要

The invention relates to a marine pipelaying system comprising a vessel (1) provided with a pipeline launch tower (6). The tower (6) comprises pipe laying equipment defining a tower firing line, and is adapted for launching a pipeline (20) along the firing line into the sea. The system furthermore comprises a hang off module (15) supported in the lower part of the firing line for clamping and supporting the weight of previously launched pipeline (20) as well as a stinger for guiding the launched pipeline (20). The stinger (10) is supported at its upper end in the lower part of the firing line. The stinger is displaceable from the firing line.

主权项

1. A vessel for laying pipe sections and an accessory into the sea, forming an offshore pipeline having a weight, the accessory having dimensions larger than a pipeline section, the vessel comprising:
a hull onto which a pipeline launch tower is mounted, the pipeline launch tower comprising pipe laying equipment defining a firing line in which the pipe sections provided with the accessory are launched into the sea to form the offshore pipeline, the pipe laying equipment including a lowering device adapted to lower the offshore pipeline; a hang off module provided at a lower end of the pipeline launch tower, the hang off module being adapted to support the weight of the offshore pipeline, the hang off module being movable between a hang off operational position in the firing line and a hang off non-active position remote from the firing line; an accessory handling system for positioning an accessory above the offshore pipeline suspended from the hang off module, wherein the accessory is to be connected to the offshore pipeline; a stinger supported at an upper end thereof by a stinger support assembly, the stinger in a stinger operational position thereof being adapted to guide the offshore pipeline generally below the hang off module in the firing line into the sea; and the stinger support assembly provided below the hang off module, comprising a stinger support ring which is supported by the hull and which is rotatable with respect to the hull and to the pipeline launch tower over at least 90° , wherein a rotation drive is provided to rotate the stinger support ring around a vertical axis, to allow for displacement of the stinger with respect to the pipeline launch tower between the stinger operational position and a remote stinger non-active position which is remote from the firing line to allow the lowering of the accessory in the firing line by the lowering device.