RU2285085C2 - Protective covering to prevent underwater pipeline scouring - Google Patents

Abstract

FIELD: hydraulic structures, particularly protective coverings adapted to be formed over underwater gas, oil and water pipelines and adapted to prevent river bottom from erosion with water stream.

SUBSTANCE: protective covering comprises longitudinal mound-like body filled with inert material and composed of lower and upper pads connected with each other along pad edges. The covering also has inner vertical rods fastened to the pads. Inert material located in the body is enclosed with flexible pack. The pads are formed of Rabitz type steel-wire fabric. Vertical rods are created of steel wire or of bars. The inert material is crashed stone and/or pebble and/or stone and/or gravel and/or sand and/or composition thereof and/or building waste (bricks, concrete cuttings and so on). The pack is bag formed of natural and/or synthetic fibers. The pad edges are connected with each other by interweaving. The body may have ballast cantledges arranged along body ends.

EFFECT: increased reliability and pipeline stability in design locations, reduced costs of scouring elimination and possibility to install protective coverings in any season regardless of weather.

6 cl, 5 dwg

Description

The invention relates to hydraulic structures, in particular to protective coatings over an underwater pipeline, gas pipeline, water conduit, designed to protect against erosion of the bottom surface by the flow of water.

A coating is known for protecting and restoring the bottom surface over an underwater pipeline (RF patent 2226586), selected as a prototype, including a carpet of reinforced elastomer bands repeatedly bent to opposite sides, stitched together in a checkerboard pattern and forming a grid with cells, while the carpet is fastened by edges facing along and against the flow of water, with anchors in the form of hollow cylinders with ballast and located above the installation site.

The disadvantage of this coating is not sufficiently reliable fixing of the coating over the pipeline and the high cost of manufacture.

The problem to which the invention is directed, is to create a simple and cheap coating, which is more securely fixed over the pipeline.

The invention provides increased reliability of the underwater crossing, a stable position of the pipeline at design elevations, a reduction in the cost of works to eliminate erosion in the area of the location of the underwater pipeline, and the use of it regardless of weather and climate conditions in winter and summer.

This is the technical result.

The technical result is achieved by the fact that the protective coating of the underwater pipeline from erosion, including a carpet of flexible, durable material with a cellular structure, according to the invention, the coating has a longitudinal hilly housing filled with inert material, consisting of lower and upper carpets fastened together at the edges and internal vertical rods connected to the carpets, while the inert material located inside the case is packed in soft containers.

Preferably, the carpets are made of metal mesh netting, and the vertical rods are made of metal wire or rods.

As inert material, gravel and / or pebbles, and / or stone, and / or gravel, and / or sand, and / or their composition, and / or construction waste (brick, pieces of concrete and others) are used.

As containers use bags and / or bags made of natural and / or synthetic fibers.

Bonding at the edges is made by weaving.

On the edges of the body is equipped with ballast weights.

The invention is illustrated by drawings.

Figure 1 shows the coating is a top view. Figure 2 presents an application of the coating to protect the bottom surface above the pipeline. Figure 3 presents an application of the coating for the repair of blurry sections of the pipeline without sagging. Figures 4 and 5 show the application of the coating in the repair of blurry sections of the pipeline with sag.

The protective coating over the underwater pipeline 1 includes a hill-shaped housing filled with an inert material 6, consisting of lower 2 and upper 3 carpets of flexible cellular material bonded together at the edges, and internal vertical rods 5 connected to the carpets. Carpets 2 and 3 are preferably made of metal netting and vertical elements are made of metal wire or rods. A variant of the manufacture of a housing made of carpets is the use of fastened strips of durable artificial materials. An inert material located in the internal cavity of the case is packed in soft containers - bags and / or bags 6 of natural and / or artificial fibers. As inert material, gravel and / or pebbles, and / or stone, and / or gravel, and / or sand, and / or their composition, and / or construction waste (brick, pieces of concrete and others) are used.

Installation of the coating when using it as a bottom coating to protect the bottom of the reservoir over the underwater pipeline 7 is as follows.

The area to be washed out over the underwater pipeline 7 is covered with a carpet of a cellular structure 2 made of a metal netting netting or of fastened strips of artificial material. The vertical rods 5 of wire or of reinforced synthetic material are preferably pre-connected to the bottom carpet. Vertical rods 5 serve to create structural integrity and to protect the coating from possible displacements under the influence of various forces. The number of fixed rods depends on the speed of the water flow, the presence of ice hummocks during ice drift, river navigation, etc. The installation of vertical rods 5 directly under water is carried out using a diver. Vertical rods 5 with a diameter of not less than 5 mm are connected to the lower carpet 2 by weaving with cells. Then, the bags with sand and gravel mixture 6, which were previously prepared and located on the boat or on ice, are lowered by a crane or a winch and piece-wise laid along the section along the entire surface of the lower carpet 2 with the formation of a hill-shaped form above the pipeline. At the end of laying, bags with inert material 6 are covered with a similar upper carpet 3. The upper 3 and lower 2 carpets are fastened at the edges, forming a joint 4. For example, compound 4 is made by weaving with a metal wire. After fastening the edges, vertical rods 5 are fixed on the upper mesh 3. In addition, weights can be installed along the edges of the grids 2 and 3 (not shown in the drawing). If necessary, upon completion of the installation of the coating using a hydraulic monitor, wash the soil for compaction.

The use of the inventive coating in the repair of a blurred area without sag (figure 3) is as follows.

At the place of erosion to the upper edge of the pipe, bags and / or bags with sand and gravel mix 6 are individually stacked, forming an artificial bottom surface. On top of the formed surface of bags with inert material 6, a coating 1 is laid according to the method described above, with a margin of at least 5 meters along the edges. The height of the laying of bags of sand and gravel 6 above the pipeline 7 should be at least 1 meter to ensure a stable position of the pipeline.

The use of coating in the repair of a washed-out area with sagging can be carried out in two versions.

In the first application (FIG. 4), a support surface is formed previously under the pipe by tightly packing the bags with sand-gravel mixture 6 and the position of the pipeline is fixed at design marks. Then, a protective coating is laid on the formed surface.

The second application (figure 5) is characterized in that the pipeline is enclosed directly in the coating, which helps to increase the reliability of protection.

The production practice of applying coating 1 to protect the bottom surface from erosion and in the repair of washed-out and sagging sections of an underwater pipeline in the Far North on the Kolva, Usa, Malaya Sinya, Bolshaya Sinya, Chikshino, Izhma, Ukhta, Pechora, Velho rivers showed its high efficiency. Coating 1 is an integral hill-shaped structure, which is securely secured with ballast (inert material serves as ballast) from possible shifts under the influence of water flow, including during ice drift and ice freezing. The inert material, packed in soft containers, maintains flowability, assumes the desired shape during installation and is protected from washing out by a stream of water. Vertical rods ensure the integrity of the structure when exposed to the upper carpet and keep it in a fixed position even when it is anchored by the anchors of the craft. The hill-shaped form of the coating along the axis of the pipeline upstream and downstream provides self-sealing of the coating with soil particles carried by the flow of water. The sloping lateral sides of the coating (with a margin of 5-10 meters at the edges) provide streamlining of the structure and increase the reliability of protecting the underwater passage from erosion.

The design is simple, cheap and affordable to use. In any hard-to-reach, remote section of the river, a protective structure can be made on the spot using industrial netting netting and soft containers with sand and gravel material, which can be taken directly on the river bank. The protective coating can be installed both in summer and in winter, regardless of the navigability of the river.

Claims (6)

1. The protective coating of the underwater pipeline from erosion, including a carpet of flexible, durable material with a cellular structure, characterized in that the coating has a longitudinal hilly housing filled with inert material, consisting of lower and upper carpets fastened together at the edges and internal vertical rods, connected to the carpets, while the inert material located inside the case is packed in soft packaging. 2. The protective coating according to claim 1, characterized in that the carpets are made of metal mesh netting, and the vertical rods are made of metal wire or rods. 3. The protective coating according to claim 1, characterized in that crushed stone and / or pebbles and / or stone and / or gravel and / or sand and / or their composition and / or waste are used as an inert material construction production (brick, pieces of concrete and others). 4. The protective coating according to claim 1, characterized in that the bags and / or bags made of natural and / or synthetic fibers are used as containers. 5. The protective coating according to claim 1, characterized in that the bonding of the carpets along the edges is made by weaving. 6. The protective coating according to claim 1, characterized in that at the edges of the housing is equipped with ballast weights.

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