Patent ID: 9651168
Date: 2017-05-16
CPC Classifications: F16L,Y10T

Claim:
1. A method for immersing a pipe from a moving ship having a longitudinal axis, where the pipe is flexible, has a longitudinal axis, transports liquid, has a cross section that can be deformed between a circular cross section and a flattened cross section and is bendable on itself longitudinally, the method comprising: providing, from the ship, the pipe with a ballasting system by equipping it with at least one longitudinal, hollow, flexible tube, immersing the provided pipe in a moving fluid along a laying axis, placing a ballast weight in the at least one tube to cause the ballasting system to act substantially as a sinker, wherein a mass of an elongate strip formed by a first part of the pipe and of the tube weighted down by the ballast weight, already immersed on a bottom of the immersion fluid, ensures that a following part of an unballasted pipe descends towards the bottom during at least part of the immersion, at a sloping angle, in conjunction with the forward movement of the ship such that a longitudinal axis of the ship and that of a ballasted pipe on the bottom are substantially parallel, the ballasted pipe thus being laid on the bottom, behind the ship, the pipe being provided with the ballasting system, itself provided with the ballast weight, by connecting the pipe and the ballasting system using a flexible connection that allows the immersed pipe to fluctuate with respect to the ballasting system as a function of non-steady movements of the immersion fluid, and wherein the ballasting system provided with the ballast weight remains essentially stationary.