摘要:
A vessel for laying a pipeline includes a plurality of workstations disposed along a pipelaying path that includes an upstream portion away from a first end of the vessel and a plurality of ramps in the region of the first end of the vessel. The plurality of ramps includes a first ramp which is disposed along the pipelaying path, whose inclination is adjustable and which has a first upstream end and a second downstream end, and a second ramp which is disposed along the pipelaying path downstream of the first ramp, whose inclination is adjustable and which has a first upstream end and a second downstream end. The downstream end of the first ramp is positioned inboard of the first end of the vessel and above the bottom of the vessel and the upstream end of the second ramp is positioned inboard of the first end of the vessel and above the bottom of the vessel. An external ramp assembly is provided, including ramps and that can be pivoted relative to one another and locked in a selected position by a locking arrangement.
摘要:
A method for repairing a defective circumferential weld joint between two pipe sections in a pipeline is described. A weld excavation machine is used to remove a weld defect. The machine comprises a weld excavating tool and a tool guiding apparatus. The machine may be modular in form allowing the machine to be dissembled into discrete portable parts. The method includes arranging the tool guiding apparatus in fixed relation to the pipeline, guiding the weld excavating tool around the pipe and along the weld joint by means of the tool guiding apparatus and using the weld excavating tool to remove material from the defective weld region. An excavation may thus be formed having parallel vertical walls. The excavation is then filled with weld material by means of a welding apparatus.
摘要:
A method of joining two portions of an underwater pipeline for conducting fluid and/or gas on the bed of a body of water, the method including the steps of: joining a telescopic sleeve, having a first coupling head, to a first end of a first pipeline portion above the body of water; positioning the first end, the telescopic sleeve, and the first coupling head in a first given position on the bed of the body of water; joining a second coupling head to a second end of a second pipeline portion above the body of water; positioning the second end and the second coupling head in a second given position, close to the first coupling head, below the body of water; and connecting the first and second coupling head hermetically below the body of water.
摘要:
The present invention relates to a method for contemporaneously recovering ammonia and carbon dioxide from an aqueous solution thereof, possibly comprising their condensates, in a synthesis process of urea, characterized in that it comprises a hydrophobic microporous membrane distillation phase of an aqueous solution comprising ammonia, carbon dioxide and their saline compounds or condensates, said distillation being carried out at a temperature ranging from 50 to 250° C. and a pressure ranging from 50 KPa to 20 MPa absolute, with the formation of a residual aqueous solution, possibly comprising urea, and a gaseous permeate stream, comprising ammonia, carbon dioxide and water. The present invention also relates to an apparatus for effecting the above method and a production process of urea which comprises the above method.
摘要:
A method of joining pipes to produce underwater pipelines, wherein the facing free ends of two adjacent pipes, aligned along an axis, are welded to define a cutback; a protective sheet of plastic material is extruded close to the cutback; and the protective sheet is wound about the cutback.
摘要:
A pipe-laying vessel for S-laying a pipeline is provided, the vessel defining a pipe-laying path extending along the vessel. The vessel includes one or more track tensioners disposed along the pipe-laying path, and a travelling clamp assembly, including a clamp mounted for movement along a length of the pipe-laying path. The vessel may also include a fixed clamp assembly located on the pipe-laying path for clamping the pipeline in a fixed position on the pipe-laying path. At least one of the clamp assemblies may include a load bearing structure and a clamp wherein a downstream-facing portion of the clamp is in an abutting relationship with an upstream-facing portion of the load bearing structure such that a downstream force exerted, in use, by the pipeline on the clamp is transmitted to the load bearing structure.
摘要:
A pipe-laying apparatus and method for laying or raising a pipeline from a vessel. The apparatus includes a first pipe gripping assembly disposed on a pipe laying path along which pipeline passes during laying, a second pipe gripping assembly disposed on the pipe-laying path, and a drive unit for causing relative movement in a direction along the pipe-laying path between the first pipe gripping assembly and the second pipe gripping assembly. The first pipe gripping assembly includes both a pipe gripping arrangement for gripping a pipe during pipe-laying and a cable gripping arrangement for gripping a cable during an operation when a cable is connected to a length of pipeline.
摘要:
Device and method for the towing of underwater pipelines (1) comprising the removable connection of a series of devices (101) to the pipeline, positioned at a suitable distance from each other, said devices being capable of providing a float buoyancy to the pipeline which varies according to the distance from the sea bed so that said pipeline can establish a substantially stable attitude at a fixed distance from the bottom, without dragging and with a neutral weight, and wherein said devices form a guide by means of at least one element (5) embedded in the sea floor in order to oppose side stress and impart variations in the direction of the movement of the pipeline.
摘要:
A method of laying underwater pipelines in the bed of a body of water, the method including laying an underwater pipeline along a given path on the bed of the body of water; breaking up a ground mass along the path to a given depth in the bed; and fluidifying the broken ground mass beneath the underwater pipeline to sink the underwater pipeline into the fluidified ground mass.
摘要:
An internal line-up clamp (20), for aligning two pipes to be welded together, includes a hi-lo measurement system, for example includes a laser source (24) and camera system (22), mounted on the internal line-up clamp (20) and arranged to make a hi-lo measurement (d), indicative of the degree of alignment of the pipes (10a, 10b). The measurement may be made when two pipes are clamped together by means the internal line-up clamp (20). The pipes may then be welded together, whilst the pipes remain clamped together in the same position, and whilst the hi-lo measurement system remains inside the pipes.