摘要:
A pipeline laying vessel for laying a pipeline (5) on a seabed, which pipeline laying vessel comprises a hull, a positioning device (6) for positioning a pipe section in a firing line (3) along which the pipeline is laid, which positioning device is supported by the hull, and a clamp (17) for holding the pipeline suspended from the vessel, wherein the clamp is located in the firing line, and comprises a support device (18) constructed and arranged to allow the clamp to hold the pipeline in a first mode wherein the clamp has a fixed position relative to the positioning device, and in a second mode (52) wherein the clamp is pivotable relative to the positioning device.
摘要:
A clamp element is provided that has a T-shaped body with laterally extending portions on either side of a radially projecting tang. A plurality of the clamp elements are joined together in an array to form a clamp assembly with the tangs facing outwardly. Straps having looped ends are disposed around the array. The looped ends of the straps are engaged with respective cross bar members. Adjacent cross bar members are connected together by means of a threaded bar which is arranged to tighten the straps around the array of clamp elements.
摘要:
Disclosed are systems and methods for controlling lateral deformation and reducing axial displacement, also referred to as walking, of a subsea conduit such as a pipeline for conveying produced hydrocarbon fluids. The systems and methods include the installation of rolling assemblies on the conduit at predetermined locations. The rolling assemblies include elements for forming rolling modules rotatable with respect to the conduit. Also disclosed is a system for monitoring displacement of the conduit over time.
摘要:
A pipeline buoyancy control assembly is operable to simultaneously retain a plurality of pipelines against buoyancy forces. Respective ends of two retaining straps corresponding to two respective pipelines engage a tie-down member of a single control assembly. The retaining straps are placed over the respective pipelines and other ends of the retaining straps are attached to additional control assemblies. Further, stresses exerted on the retaining straps when the pipelines are subjected buoyancy forces are minimized by the unique structure of the tie-down member and the manner by which the retaining straps attached thereto.
摘要:
A curvature limiter for a hydrocarbon transferring subsea system comprising a flexible tubular member through which an intermediate portion of the flexible hydrocarbon pipe passes. The flexible tubular member has a plurality of successive, substantially cylindrical sections which are hingedly mounted with respect to each other. At a predetermined maximum displacement thereof, the tubular member defining a mean plane in such a way that the flexible tubular member forms a mean curvature having the predetermined curvature radius of this mean plane.
摘要:
A support assembly for a flexible line comprises a hanger to suspend the flexible line from an offshore oil rig without subjecting the line to a bending stress adjacent the support assembly, a frame supporting the hanger, and a connector coupled to the frame to removeably connect the support assembly to the rig. In an embodiment, the support assembly further comprises a base that may be a plate, an open-ended box, or a plurality of beams. In another embodiment, the flexible line includes an end comprising a swivel plate that mates with the hanger.
摘要:
A pipeline connection assembly includes a landing platform and rotary or swivel connection hub which may be attached to a pipeline branch, termination, or manifold. The landing platform is mounted so that it may be rotated about the connection hub. This permits the installation of a subsea connection on a near level platform and allows the pipeline to be laid subsea with greater roll angles than would be acceptable otherwise. Orientation of the landing porch horizontally removes the requirement to manufacture the connection jumper to compensate for the roll differences in the hubs. In the preferred construction, the elevation of the platform can be adjusted by a remotely operated vehicle (ROV) and locked into place once the adjustment is completed.
摘要:
An apparatus for laying marine pipelines of the type in which the pipeline is assembled along a horizontal axis on board a pipelaying vessel prior to being launched therefrom; in which the pipeline is plastically bent to a desired launch angle and, in most cases, at least partially straightened thereafter. In preferred embodiments, the pipeline is bent through an angle greater than 90.degree.. In the most preferred embodiments, the pipeline is diverted through an angle of substantially 270.degree., plus or minus an angle allowing variation in the launch angle from the vertical, and crosses itself prior to entering the water. The pipeline (102) is diverted by being passed around a wheel-like diverter structure (104), the pipeline being assembled in multiple fabrication lines to produce stalks which are aligned and connected in a central firing line prior to being fed around the diverter structure. Other variations are also described.
摘要:
A method for laying a pipeline on a surface located under water such as a deep sea bed. The pipeline is held fixedly by tensioners having tensioning elements each extending between a clamping member engaging on the pipeline and a support member connected to a vessel. Tensioning is accomplished by sets of endless clamping bands which apply a braking action to the pipeline. A set of clamping jaws is clamped fixedly to the pipeline and moves along with the pipeline from a starting position to a releasing position. As a set of clamping jaws is clamped to the pipeline, another set of clamping jaws is released from the pipeline and returned to a starting position to continually repeat the cycle of holding and releasing of the pipeline.
摘要:
The system for deploying cable having nodes according to the present invention includes a tubular member, first and second restrictors, and a controller. The cable having nodes travels through the tubular member from a cable supply point to a deployed point. The deployed point is a fluid medium at a higher pressure than the cable supply point. The first and second restrictor form part of the tubular member with the second restrictor being disposed closer to the deployed point. The first and second restrictor have at least a first and second operating position. In the first operating position the restrictors allow the cable to pass, and in the second operating position the restrictors allow both the cable and the nodes to pass. Depending on their operating state, the first and second restrictor restrict the flow of the fluid medium through the tubular member. The controller controls whether the first and second restrictor are in the first and second operating position. The first and second restrictor may, for example, be multi-port blowout preventers.