RU2657372C2 - Method of pipeline laying on the bed of water body - Google Patents

Abstract

FIELD: instrument engineering.

SUBSTANCE: invention relates to methods of pipeline laying along the bed of water bodies. Method of pipeline laying along the bed of water bodies involves laying the pipeline on the joint piles that are previously fixed on the bed of a water body in a single row, followed by fastening with clamps. Joint piles consist of screw piles with additional threaded part and removable extensions. Screw piles are drilled into the ground using removable extensions, which also used to provide the required orientation of the buoyant pipeline before it is flooded. Additional threaded part of the screw piles is used to fix the pipeline at a given depth with the help of upper and lower half-clamps with a locking system, as well as supporting and fixing nuts.

EFFECT: method ensures safe work while pipeline laying, the possibility of adjusting the sag, the ability to adjust the level of stress-strain state, the possibility of full visual inspection of the pipeline, the minimum labor costs for securing the pipeline on the supports.

1 cl, 4 dwg

Description

The invention relates to methods for laying pipelines along the bottom of reservoirs.

Known methods of laying pipelines under water, described in departmental building codes BCH 010-88 "Construction of trunk pipelines. Underwater Transitions. ” In the construction of floodplain sections of underwater passages for ballasting (flooding) of pipelines, individual loads, concrete coatings, as well as fixing of pipelines with anchors, are used. [1] (BCH 010-88 “Construction of trunk pipelines. Underwater crossings”, section 4).

A known method of laying a pipeline along the bottom of a reservoir [2] (Patent No. 2308631 "Method for laying a pipeline along the bottom of a reservoir"). The method is implemented in the following way. Beacons mark the route of the floating means for laying the pipeline under water. They fix the floating device, assemble the pipeline, put on sinkers in the form of rings, on the inner surface of which rubber rollers are located, the pipes are laid on paired support-screw piles pre-fixed at the bottom. A beam with fasteners is installed on each pair of piles, a lodgement is placed on the beam. After installing the pipeline, it is fixed to the supports using clamps.

The disadvantages of this method are:

- the need for drilling from two sides when installing paired piles;

- lack of ability to adjust the sag;

- the inability to adjust the level of stress-strain state (VAT) of the pipeline;

- the high complexity of the installation of supports and fastening the pipeline;

- high requirements for the accuracy of laying the pipeline on the pillars of supports.

The closest in technical essence and the achieved effect to the claimed method is the use of underwater piping devices [3] when laying a pipeline along the bottom of a water barrier [3] (Patent US 4492493 A). The device is a screw pile with an arc-shaped clamping clamp coaxially rotating on it. The use of the known device involves laying the pipeline to the bottom - from the vessel, using a lifting device with the function of drilling screw piles for the existing shank on them. In this case, the positioning of the screw pile and the pipeline relative to each other occurs due to the fixing of the pile on the pipeline, before its descent, by an arc-shaped clamp with clamp [4] (Patent US 4492493 A, Fig. 7). The pipeline in the known patent does not have its own buoyancy.

The disadvantages of the known device are:

- the trajectory of the pipeline fixed under water in a vertical plane is not optimal due to the variable topography of the bottom;

- lack of ability to adjust the sag;

- the inability to adjust the level of stress-strain state (VAT) of the pipeline;

- the possibility of bending a screw pile when it is screwed into the ground from the bending moment that occurs when the pipeline is pressed to the ground [5] (Patent US 4492493 A, Fig. 6).

The aim of the invention is to provide a method of laying a pipeline along the bottom of a water barrier, providing:

- the ability to adjust the sag;

- the ability to adjust the level of VAT;

- the exception of the bending of screw piles when fixing the pipeline;

- the possibility of complete visual control of the state of the pipeline;

- minimum labor costs for the orientation of the pipeline before flooding and when mounting the pipeline on supports.

The specified goal is achieved through the use of:

- composite piles installed at the bottom of the reservoir, consisting of screw piles with an additional threaded part and removable extensions;

- half clamps with a locking system;

- supporting and fixing nuts.

The essence of the present invention lies in the fact that the proposed method of laying a pipeline along the bottom of a water barrier, including attaching the pipeline to screw piles installed on the bottom of a pond in one row, according to the invention uses composite piles consisting of screw piles with additional threaded piles installed at the bottom of the pond part of removable extension cords, while removable extension cords are used not only to drill screw piles into the ground, but also to provide the required orientation with buoyancy boprovoda prior to flooding, it simply rests on them, and the additional threaded portion of screw piles used to fix the pipe at a predetermined depth, with the upper and lower poluhomutov with a locking system, as well as the support and fixing nuts.

In FIG. 1-4 shows the stages of the implementation of the method of laying the pipeline along the bottom of the water barrier, where

1 - screw pile;

2 - removable extension cord;

3 - clamp;

4 - a basic nut;

5 - pipeline;

6 - lower half-clamp;

7 - upper half-clamp;

8 - fixing nut;

9 - castle system.

A method of laying a pipeline along the bottom of a water barrier is as follows.

Stage 1 (see Fig. 1).

Using a drilling rig, in the bottom of the reservoir, suitable for the geological structure, composite piles are drilled in one line, along a planned trajectory, which consist of screw piles 1 with an additional threaded part, removable extensions 2 and clips 3, which protect the components of the pile from unauthorized separation . Before connecting the screw piles 1 and removable extensions 2 to each other, before drilling, the support nuts 4 are screwed onto the threaded parts of the first. After drilling, the support nuts 4 are set along the planned path of the pipeline 5.

Stage 2 (see Fig. 2).

The lower half-clamps 6 are put on composite piles, which are lowered by their own weight onto the support nuts 4, while the lower half-clamps 6 should be oriented in one direction perpendicular to the path of the pipeline 5. The pipeline prepared on the shore 5, which has its own buoyancy, is transported by tow to the installation site . After the pipeline 5 rests against the removable extension cords 2 of the composite piles, they put on the upper half clamps 7, which cover the pipeline 5 from above.

Stage 3 (see Fig. 3).

The pipeline 5 is filled with water, and under its own weight, together with the upper clamps 7, lowers to the lower half-clamps 6.

Stage 4 (see Fig. 4).

The clamps 3 are removed from the composite piles and removable extensions 2 are removed. The fixing nuts 8 are screwed onto the threaded parts of the screw piles 1. The pipe 5 is fixed, after which water is pumped out of it.

To increase the reliability of fixation of the pipeline 5 during its flooding, by increasing its coverage, the upper and lower half-clamps 6, 7 are equipped with a locking system 9.

The proposed method of laying the pipeline 5 along the bottom of the water barrier will provide not only its reliable fixation, but also the ability to adjust the sagging of the pipeline 5 using the support nuts 4, having previously released the fixing nuts 8.

To avoid biting the lower and upper half-clamps 6, 7 when descending along the pile, the length of the landing hole in them should be at least 3-5 of its diameters.

To avoid damage to the thread on the screw pile 1 when lowering the lower and upper half-clamps 6, 7, it is recommended to cover their mounting holes with plastic.

The proposed method of laying the pipeline along the bottom of the water barrier is recommended for underwater areas where busy shipping is not supposed to exclude possible hooks by fishing trawls and when anchoring.

INFORMATION SOURCES

1. BCH 010-88 “Construction of trunk pipelines. Underwater transitions ”, section 4.

2. Patent No. 2308631 "Method for laying a pipeline along the bottom of a reservoir."

3. Patent US 4492493 A.

4. US Pat. No. 4,492,493 A, FIG. 7.

5. Patent US 4,492,493 A, FIG. 6.

Claims (1)

A method of laying a pipeline along the bottom of a water barrier, which includes attaching the pipeline to screw piles installed in the same row at the bottom of the reservoir, characterized in that it uses composite piles installed at the bottom of the reservoir, consisting of screw piles with an additional threaded part and removable extensions, Removable extension cords are used not only for drilling screw piles into the ground, but also for providing the required orientation of the buoyant pipeline before flooding, it just abuts against them, and An additional threaded part of screw piles is used to fix the pipeline at a given depth using the upper and lower half-clamps with a locking system, as well as supporting and fixing nuts.

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