Method for initial laying of ultra-deep water subsea pipeline by utilizing gravity anchor

Abstract

The invention discloses a method for initial laying of an ultra-deep water subsea pipeline by using a gravity anchor. The method comprises the following steps that a long baseline positioning beacon array is installed at the laying position of the subsea pipeline, and under the assistance of an underwater robot, the gravity anchor is accurately installed in the initial laying area of the subsea pipeline in advance, the subsea pipeline is controlled to vertically enter water and descend downwards through a stinger through a tensioner, the subsea pipeline is freely suspended and lowered to the seabed under the assistance of the deepwater underwater robot and a long baseline positioning system until the initial seal head of the submarine pipeline reaches the position near the submarine gravity anchor, a hook reserved by the initial seal head is connected with an annular buckle reserved by the gravity anchor through the underwater robot, and the gravity anchor is used for providing bottom tension for submarine pipeline laying to conduct ultra-deep water submarine pipeline laying. The problems of initial laying of the ultra-deep water subsea pipeline, use limitation of a high holding power anchor and a suction anchor and initial laying of the ultra-deep water subsea pipeline after the ultra-deep water subsea pipeline vertically enters water are successfully solved.

Description

technical field [0001] The invention relates to the field of submarine pipeline laying, in particular to a method for initial laying of an ultra-deep sea pipeline by using a gravity anchor. Background technique [0002] With the increasing demand for deepwater and ultra-deepwater submarine pipeline laying, the traditional method of using large anchors for the initial laying of deepwater submarine pipelines can no longer meet the requirements. The reasons are as follows: 1. Ultra-deepwater submarine pipeline terminals are generally designed with water The lower structure requires high-precision installation, and the target area of ​​the high-holding anchor is large, and it is difficult to accurately locate it in ultra-deep water; 2. The high-holding anchor in ultra-deep water requires a super long starting cable, and it is difficult to arrange the tugboat. 3. Ultra-deep water The laying of deep-water submarine pipelines has a large uplift force, and the high-holding force anc...

AI Technical Summary

Problems solved by technology

[0004] The invention provides a method for initial laying of ultra-deep water sea pipes using gravity anchors, which solves the problem that the grasping anchor is difficult to accurately locate in ultra-deep water

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