RU76026U1 - BOTTOM SOIL PROTECTION FROM FLUSHING - Google Patents

Abstract

A mobile temporary protection of bottom soil from erosion is proposed, in which zones of protection against the effects of waves are formed. This is due to the fact that the floating means - the tube frame itself serves as part of the protection of the bottom soil from erosion of the bottom soil both inside the enclosed space and from its outside. Moreover, from the outside, the tube frame has a flexible geotextile fabric, which is located on the bottom soil and pressed with the help of flexible weights, for example, anchor chains. Inside the tube frame, another geotextile web is fixed, which is directly located under the control panel.

Description

This utility model relates to the means for preventing erosion of bottom soil both around the perimeter of a floating submersible drilling rig (FPBU) and under it during exploratory drilling on the offshore shelf.

Known protection of bottom soil from erosion, which is created from planting material (USSR Author's Certificate No. 1392183, class ЕВВ 3/02, 1988. Poiker X. Cultural Landscape. Formation and Care. - M.: Agropromizdat, 1987, p. 89, 96 and 97). It is formed on the bottom soil by laying on it a reinforcing element consisting of two shells and alluvial soil around the reinforcing element. Then harden the washed-up soil to a depth exceeding the level of wave action on the foundation soil. Deep hardening of the reclaimed soil is carried out by supplying a monolithic solution into it. Then, the outer shell of the reinforcing element is removed from the soil, and the inner shell with planting material and soil is left in the hardening zone.

This well-known erosion protection of the bottom soil has a significant drawback. It can not be used as a temporary dynamically displaced protection of the bottom soil for the use of SSF at a new installation site. This is due to the purpose of the mentioned protection, namely, stationary use, as indicated by the need for monolithic solution of the reinforcing element.

A device is known for protecting bottom soil from erosion (US Patent No. 4722639, class ЕВВ 3/04, 1988. PCT Application No. 085/03318, class. ЕВВ 3/04, 1985). This erosion protection of the bottom soil contains vertically located floating panels of synthetic material with flexible anchor elements that are connected to the anchors by the ends above the bottom soil. Holes are made in the lower part of the panels. Flexible anchor elements are passed through them, combining the panels in a single package.

The disadvantage of this known protection of the bottom soil from erosion is that it is not able to provide reliable protection against erosion of the bottom soil not only under the SSFB, but also around it. This disadvantage is due to the fact that the known device cannot exclude the possibility of soil slipping out from under the SSBF caused by different vibrations of sea water, such as: vertically lowered waves, either their longitudinal movement, or bottom currents, and other reasons.

Known protection of bottom soil from erosion and the method of its installation (RF Patent No. 2054079, IPC ⁶ EV 3/04,

publ. 1996.02.10), including vertical floating panels made of synthetic material placed above the bottom of the reservoir with flexible anchor elements that are connected by ends to the anchors. Moreover, holes are made in the lower part of the panels through which flexible anchor elements are passed, combining the panels in a single package. Thus, the lateral edges of the panels are attached to each other alternately on each side with the formation of a zigzag line in the plan.

This well-known technical solution is selected as a prototype, as it has the largest number of essential features that match the essential features of the claimed utility model. In addition, it is aimed at solving the same problem as the proposed utility model.

But the prototype has a significant drawback, namely, with its help it is impossible to provide reliable protection against erosion of the bottom soil not only under the SSFB, but also around it. This disadvantage is due to the fact that the known device cannot exclude the possibility of soil slipping out from under the SSBF caused by different vibrations of sea water, such as vertically lowered waves, or their longitudinal movement, or under bottom currents, as well as other reasons.

The well-known practice of creating a similar purpose of protecting bottom soil from erosion requires the use of SSBP to create such protection of bottom soil from erosion that could be quickly

install in one place and remove quickly for reuse in another place.

In this case, it is necessary to obtain the following technical results:

- to exclude the possibility of erosion of bottom soil under the SSBP, as well as around it;

- to create protection of the bottom soil, which could be repeatedly applied without its destruction at the new installation site of the control panel.

The problem is solved as follows. In the well-known protection of the bottom soil from erosion, containing the sheet and flexible weights associated with it, according to the present utility model, a pipe frame and an additional sheet are introduced, moreover, the pipe frame is made with controlled buoyancy and has a metal skirt on the bottom, to which on the outside, a web with weights is attached, as anchor chains used, and an additional web is tensioned inside the tube frame, while the web is made of geotextile with negative buoyancy.

Such a new technical solution with all its essential features allows you to achieve the following technical result:

- get reliable protection of the bottom soil from erosion both around and below the SSBP, which is achieved by completely eliminating the contact of the soil around the SSBP with the excitement and the flow of water, in particular, within 10 m from the bow or more and the stern and a little less along the sides of the SSBP . This is due to the fact that in the proposed protection of the bottom soil from erosion there are geotextile webs,

having negative buoyancy, attached to the tube frame, both from the outer side of its contour, and from the inner side of its contour. In addition, a metal skirt is located under the tube frame, which also contributes to the retention of soil under the SSF.

The proposed protection of the bottom soil from erosion has significant differences from the prototype, which are as follows:

- a tube frame with controlled buoyancy has been introduced, and the canvases have negative buoyancy, which makes it possible to create an on-board bottom soil protection system around the control panel;

- inside the pipe frame, a geotextile web is stretched, which directly protects the bottom soil under the SSBF from the interaction of waves with it and ensures reliable fixation of the SSBU on the bottom soil;

- a metal skirt is made under the bottom of the pipe frame, to which the said webs are fixed along the contour of the pipe frame.

On this topic, the applicant conducted a patent information search, which showed that the proposed set of essential features of the claimed protection of the bottom soil from erosion was not found. Therefore, a real useful model can be recognized as new.

The essence and practical application of the claimed utility model is confirmed below by the following material.

The drawing shows:

Figure 1 is a top view of the location of the protection of the bottom soil from erosion with installed on it PPBU (shown conditionally);

Figure 2 is a cross section of the protection of the bottom soil from erosion with one of the possible options for a flexible canvas with a load in the form of chains;

Figure 3 is a cross section of the protection of bottom soil from erosion with another of the possible options for a flexible canvas with a load in the form of chains.

The practical applicability of the claimed utility model is confirmed below by the following description.

The proposed protection of the bottom soil from erosion contains a pipe frame 1 - frame (Fig.1, 2, 3). This frame 1 has controlled buoyancy, i.e. made with the corresponding ballast compartments (not shown), which can be filled with water to immerse the frame 1 on the bottom soil 2 (Fig.2, 3), or be filled with air to stay afloat. On the outside of the tube frame 1 attached waterproof flexible with negative buoyancy fabric 3, for example, of geotextiles. This web 3 can be attached to the tube frame from above (Figure 2). Then it, when the protection is deployed at the bottom of the reservoir, forms an elepsoid deflection (Figure 2) from the outside of the tube frame 1 (Figure 2), which meets the movement of the bottom wave and directs it upward with twisting in the form of a turbulent flow, creating an additional barrier from it to the next burst of the bottom wave. The weights 4 can be located on the surface of the web 3 and are fixed in the upper part of the pipe frame 1. They

press the canvas to the soil 2 outside the outer limits of the said frame 1 (Figure 2). The weights 4 can be fixed along the free edges of the web 3 along its entire contour, which is preferable (Figure 3). Weights 4 also hold the bottom soil from erosion.

In the case when the web 3 is fixed on the pipe frame 1 in its lower part, the web 3 immediately straightens parallel to the bottom soil 2 (Figure 3) and is pressed against it by a load 4, i.e. chains connected with its free edges around the perimeter.

Inside the pipe frame 1, another sheet 5 is fixed along its inner perimeter. It is similar to the sheet 3 fixed on the outside of the pipe frame 1. This sheet 5 is placed on the bottom soil 2 directly under the control panel.

It should be noted that the shape of the pipe frame 1, and, consequently, of the entire proposed protection of the bottom soil from erosion is determined taking into account the following possible factors:

- Reduced drag when towing due to rounding of the corners of the contour and the formation of the stern and fore ends at the tube frame 1 (not shown in the drawing).

- Ensuring some stability on the course by giving the contour of the pipe frame 1 a wedge shape (the width in the bow is slightly greater than the width in the stern).

- Positioning with the help of tugboats mounted on their own anchors (not shown in the drawing), which is traditionally carried out in other marine operations with floating barges.

- Immersion by adopting ballast (sea water) inside the pipe frame 1.

- Surfacing due to debalancing. If necessary, in the case of suction and / or siltation, using a crane vessel or tugboats (not shown in the drawing).

- The stability of the protection on the bottom soil 2 is ensured not only by crushing it of the SSFB, but also:

- the negative buoyancy of the proposed protection of the bottom soil 2 from erosion;

- by loading in the form of chains of 4 anchor or other elements.

Thus, a very interesting and promising mobile system for protecting bottom soil from erosion was created, in which it is possible to form the corresponding opposing elements to the movement of various wave motions of the liquid.

Note that the proposed protection of bottom soil from erosion is first made in the factory. Then it is transported over the surface of the reservoir to the installation site on the bottom soil. The transportation process of the proposed protection of the bottom soil is governed by the rules of navigation and other marine navigation rules and it is not included in the subject of these inventions. Therefore, this application is not considered. All other operations related to immersion of such a structure are also known, since giving buoyancy or flooding to the tube frame is a known process. It is carried out using appropriate pumps and controlled by them.

devices with which the mentioned pipe frame should be equipped, or connected with them. After the aforementioned protection has been sunk and deployed on the bottom soil, the SSFU enters its internal cavity and is installed on the inner panel of this protection, pressing it to the bottom soil. At the end of the drilling operations, the SSBF pops up, goes beyond the limits of the mentioned protection, and gives the pipe frame buoyancy. But, in the beginning, the anchor chains and the web pressed by them are folded, they are fixed on the pipe frame and after giving the pipe frame buoyancy, all the protection pops up. Then it is transported to a new installation location.

Claims (1)

Protection of the bottom soil from erosion, comprising a sheet and flexible weights associated with it, characterized in that a pipe frame and an additional sheet are introduced, the pipe frame being made with controlled buoyancy and has a metal skirt on the bottom of the entire contour to which the sheet is connected from the outside with weights, for which anchor chains are used, and an additional web is stretched inside the tube frame, while the web is made of geotextile with negative buoyancy.