摘要 |
The invention consists of a method and apparatus for laying a pipeline, such as an oil duct or a gas duct, in a body of water, wherein the pipeline, or a section thereof, is enclosed within a ballast tube such that an intermediate space is formed between the pipeline or pipeline section and the ballast tube, said space being filled with a liquid less dense than water, such as a light hydrocarbon, while the pipeline is being laid, but may be filled, after the pipeline has been laid, with soft water or with a liquid heavier than water such as a grouting having a base of a hydraulic or hydrocarbon binder. The invention also comprises the provision of a plug at one end of an assembly of pipeline section and ballast tube whereby a free end of said assembly may be secured as by welding to a second assembly of pipeline section and ballast tube at a position remote from the liquid contained in the intermediate space in said first assembly.
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