RU2377388C2 - Well plugging back method with bridge creation, equipment for execution and slurry barrier - Google Patents

Abstract

FIELD: oil-and-gas production.

SUBSTANCE: invention related to underground reservoir, particularly to method of cement bridge construction in a well, with production string installation at the same time. Device includes piping string and connected to it bearing pipe with central pass canal and radial holes. Slurry barrier connected to bearing pipe, consisting from folded material and auxiliary constructions, which perform barrier opening and keep it opened. Barrier executed as void shell with closed around bearing pipe volume. Auxiliary constructions executed as a flexible frame, consisting of multiunit tapes, which cover shell in the barrier shut of position. Also device has centralisers, installed on bearing pipe by the both sides of the barrier. Connected to each other devices forms well production string. For the method execution connect bearing pipe to pipe string, descent the barrier in to the well on a tubing string, which is shut of in correspondence to not cased part of the well, chosen for bridge creation. Pump slurry down though piping string and bearing pipe till shell complete volume filled in, which leads to barrier displacement form shut of to opened position.

EFFECT: increase wells with complicated profile plugging quality, and avoid equipment damage during operation.

8 cl, 7 dwg

Description

The invention relates to the field of construction of underground reservoirs, in particular to methods and devices for creating cement bridges in a well with the simultaneous installation of production casing.

A well-known apparatus for plugging wells / GB 618997, IPC ЕВВ 33/136, 1949.03.02 /, consisting of a channel tubular element attached between the ledge and the cement front part, a tubular body having a central part of a reduced diameter, allowing to form a cavity equipped with shoulder mechanisms , between the body and the tubular element. A rubber skirt installed in the cavity forms a check valve with holes in the body. During operations prior to cementing, fluid flow through these holes is prevented by a sleeve held in its original position by shear screws, the fluid flows down through the tool and out into the well through a check valve. When everything is ready to start the cementing operation, the ball is fed through the pipe string into the socket on the sleeve, blocking the passage through the tool. The fluid pressure in the casing increases, the screws are cut off, the sleeve drops down, opening holes for lowering the cement along the string into the space between the casing and the well through the check valve and through the holes. When the screws are cut off, the bolt attached to the head of one of them, and which abuts against the steel strip element, is pushed out, thereby allowing the tape to fall freely and release the annular barrier formed from the spring-loaded lobe segments. This barrier closes the space between the element and the well, preventing liquid cement from falling below the tool.

The disadvantage of this device is that the presence of a significant number of mating moving parts that require high accuracy in the manufacture reduces the reliability of the entire system, the lobe segments do not allow reliable isolation of the cavity above and below the apparatus for plugging wells. In addition, the absence of protective elements increases the risk of damage to the lobed segments during tripping.

Also known is the bridge used for cementing wells in the ground / US 3039534, IPC ЕВВ 33/068, ЕВВ 33/136, 1962.06.19 /, consisting of a thin rounded body made of flexible material having a thin stable rounded and non-perforated central part with a central hole in it there is a relatively narrow protruding edge on the periphery of the central part below, on the outer part of the body, segments are arranged consisting of many constituent elements protruding radially from the central part and bending in this part through these constituent elements Comrade, can interact with the walls of an open wellbore, ensuring its overlap. A plurality of petals located at a distance from each other are pivotally attached at their inner ends to the holes in the integral support structures on the lower side of the central part of the housing and the adjacent peripheral flange. Each of the petals has a coil spring attached to them and to the housing for bringing the petals to the open position. In this position, the petals are located around the body and are adjacent to the walls of the well to prevent the body from moving downward, the petals are bent relative to the axis of the body, are located and intersect relative to each other so as to be located next to the walls of the well in the specified central part of the body and held under pressure by coil springs with a wedge-shaped pin at the end of the positioning pole inserted inward, extended through the well and frictionally fixed in the well to hold I was there until the body is placed in the borehole at the end of a pole, and the petals are drawn coil springs while removing the wedge-shaped pin.

The disadvantage of this device is that the lobe segments do not allow reliable isolation of the cavities above and below the apparatus for plugging wells, their shape with an outer edge that is inscribed in a circle eliminates the possibility of overlapping an open wellbore with an unpredictable profile, the presence of a significant number of mating moving parts , requiring high precision in the manufacture, reduces the reliability of the entire system, the design does not have a pipe string that could be used as a e casing.

A well-known installation for plugging wells with production casing / GB 1294721, IPC ЕВВ 33/136, 1972.11.01 /, which includes upper and lower sets of knives with springs that push them out so that the knives can abut against the casing strings, and the blades of the basket, each of which is equipped with springs that push the blade out. In use, the device lowers down on the rope until the spring blades on the trigger go to the end of the cable. Then the blades bend outward so that the sleeve rises and thus the balls are released. A spring pushes the rod down, forcing the dies to extend outside the cup (sleeve, sleeve) in order to abut against the casing. The dies are released by the trigger and the glass, which are displaced upward in order to abut against the casing. The shock force cuts the pin, freeing the mechanism and the glass, while the blades of the basket open. Balls of gravel or glass are poured onto the blades of the basket, while the cement enters the mechanism, which, in turn, has a glass disk, broken by a device holding the gravel. In another embodiment of the device, gravel may be omitted in the container.

The disadvantage of this installation is that it can only be used in cased wells, the need to use wireline equipment for the delivery of gravel increases the cost of the process, the presence of a significant number of mating moving parts that require high precision in manufacturing reduces the reliability of the entire system.

Known cementing basket / US 3955625, IPC ЕВВ 33/136, ЕВВ 33/13, 1976.05.11 / for use in cementing trunks of oil and gas wells. Unlike known baskets in which metal slats are used, wire loops such as steel spring wire for inflexible elements of the basket petal are used in this invention to form the inflexible portion of the basket petals.

The disadvantage of this cementing basket is that it can only be used in cased wells or open shafts, since in the case of unauthorized exit from the cased part of the well into the open well, this device cannot be returned to its original position, in addition, the weak bearing capacity of the spring wire loops significantly limits the volume of grouting mortar. The absence of radial holes hydraulically connecting the internal cavity of the carrier pipe with the annulus does not allow direct injection of grouting mortar, which significantly limits the scope of this device.

Also known is the downhole barrier / US 5667015, IPC ЕВВ 33/136, ЕВВ 33/13, 1997.09.16 / for separating two liquids in a gas or oil well. The barrier includes opposed rails that protrude obliquely from a centrally located fixture. A set of upper and lower tarpaulin materials can be attached to each of the sets of rails to provide a greater sealing effect. In a preferred embodiment, the rails are also located crosswise to minimize the overall length of the barrier, as well as maintain the required functionality.

The disadvantage of this device is that the presence of two oppositely located barriers significantly complicates the design, and during the descent of the device into the well, the presence of a constantly open lower barrier will impede the free flow of well fluid and thereby make it difficult to lower the device to the installation site. In addition, the presence of a supporting rod for lowering the device will significantly complicate the drilling of a cement cup due to the presence of a steel supporting rod in it.

Closest to the claimed method and device for plugging a well, as well as a barrier for grouting, is a method and a unit for plugging wells according to the patent US 6454001, IPC ЕВВ 33/136, ЕВВ 33/13, published 2002.09.24. One of the options of the method is that they determine the spatial characteristics of the well in the place chosen for the installation of the bridge before the barrier is lowered into the well and select the dimensions of the barrier so that it interacts with the well in the place selected for the installation of the bridge, attach the well barrier to the support pipe, attach the support pipe to the pipe string with a barrier. The grouting barrier contains a folding material and has many supporting structures attached to it. Auxiliary structures are pivotally connected at one end to the carrier pipe, while the structures rotate independently of each other. The second ends of the auxiliary structures interact with the uncased part of the well. The liquid barrier is lowered on the pipe string to the place chosen for the bridge to be installed in the uncased part of the well, while the barrier is kept closed before and during the descent of this barrier to the selected location, the barrier is moved from the closed position to the open position in which the barrier interacts with the wellbore, and support the barrier in an open position in which the fluid barrier blocks the well at a location selected for the installation of the bridge by creating a downward force. The grouting fluid is displaced through the pipe string to bring the grouting fluid into the well above the fluid barrier, while the barrier is attached to the pipe string, the downward force on the barrier is increased after the fluid barrier reaches the location chosen to install the bridge, support the weight of the liquid barrier and the grouting fluid in the well by means of a pipe string without a packer in the well, the pipe string is removed after the grouting fluid has hardened to such an extent that it can maintain its GOVERNMENTAL weight downhole.

According to US Pat. No. 645,4001, one embodiment of a device for plugging a well in a location selected for installing a bridge comprises a pipe string lowered into the well with a central passage channel, a pipe carrying a central passage channel connected to the pipe column, and the central passage channels of the column the pipes and the carrier pipe are interconnected, the carrier pipe has many holes that intersect its central channel, a liquid barrier located around the carrier pipe below the many holes, many the supporting structures of the barrier pivotally connected to the carrier pipe and attached to the barrier, and the load acting on part of the structures of the liquid barrier with the force directed downward, so that the structures will rotate radially from the carrier pipe and force the liquid barrier to open before interacting with well.

According to the aforementioned patent, the grouting barrier consists of folding tarpaulin material and supporting structures that prevent it from opening outside a completely open place and supporting the barrier in an open position in the place chosen for installing the cement bridge, with one end pivotally connected to the carrier pipe, which contains a Central passage channel with many radial holes intersecting its Central channel for the exit of cement slurry. In this case, the lower level of the barrier is located below the radial holes of the carrier pipe. The barrier is held in a closed position by detachable slings twisted around the barrier, the traction of which is overcome when the barrier is installed in the place chosen for the bridge. In the open position, the barrier extends radially outward from the carrier pipe, touching the well at a location selected for the installation of a cement bridge.

The disadvantage of this method and device is that during the descent of the assembly into the well there is always a risk of damage and complete destruction of the barrier to the solution due to its friction against the walls of the well, especially at the time of passage of the pipe joint joints that make up the pipe string. In addition, the design provides for the destruction of the carrier pipe after installing the cement bridge, followed by drilling a cement cup, lowering the production casing and another stage of cementing. The mechanism of forced opening of the liquid barrier (under the action of a force directed downward) consists of a significant number of interconnected moving elements, which reduces the reliability of the entire unit. The rigid drop-down frame of the fluid barrier does not allow completely blocking the open wellbore due to the fact that the well profile has a complex cavernous shape. The tarpaulin material is fastened only to the elements of the drop-down frame, leaving the junction of the liquid barrier and the carrier pipe open, through which cement slurry can flow.

The objective of the invention is the creation of a high-tech method of plugging the uncased part of the well with the simultaneous installation of the production string, as well as devices for implementing this method, with high reliability with sufficient simplicity of design.

The task in the method of plugging a well with a bridge is to determine the spatial characteristics of the well in the place chosen to create the bridge, use a cement slurry barrier consisting of folding material and supporting structures holding it, select the barrier dimensions so that it in the open position interacted with the wall of the uncased part of the well along the entire perimeter in the place chosen to create the bridge, determine the volume of the displaced the mortar required to create a bridge, fix the barrier along the radius to the supporting pipe, provided with radial holes for the cement slurry to exit into the cavity of the barrier, attach the supporting pipe with the barrier to the pipe string, lower the barrier in the closed position on the pipe string to the place chosen to create bridge in the uncased part of the well, grout is displaced down the pipe string and the carrier pipe to catch it with a barrier until a bridge is formed, before lowering into the well, attach to the carrier pipe above and the barrier centralizers, whose diameters exceed the transverse dimensions of the barrier in the folded position, use the barrier material in the form of a hollow shell with a volume under the grout closed around the carrier pipe, while moving the barrier from the closed position to the open ensures the grouting of the grout until the shell volume is completely filled, and interconnected pipe string, a supporting pipe with centralizers and a barrier form a production string.

As cement slurry can be used cement mortar.

The problem in the device for plugging a well is solved due to the fact that in a device including a pipe string with a central passage for supplying grout, connected in series and lowered through the technical column of the well, the pipe string having a length sufficient to reach the uncased part of the well below the technical columns supporting pipe with a Central passage channel connected to the Central passage channel of the pipe string and radial openings for the exit of cement grout, a cement slurry barrier connected radially to the carrier pipe, consisting of folding material and supporting structures that open the barrier and hold it in the open position, the lower level of the barrier is below the radial holes of the carrier pipe, according to the invention contains at least two a centralizer mounted on a carrier pipe on either side of the barrier, the diameters of which are larger than the transverse dimension of the folded barrier, the barrier material is made in the form of a hollow shell, capped in the upper part with openings providing hydraulic connection of its internal volume with the annulus, with the volume closed around the carrier pipe, in the open position of the barrier completely filled with grouting fluid and in contact with the wall of the uncased part of the well around its perimeter, and the pipe string carrying the pipe with centralizers and a barrier form the production casing of the well.

The device may include a check valve located on the carrier pipe below or above the lower centralizer.

In addition, the shell can be attached to the carrier pipe by the upper and lower mouths, the upper neck being fixed with the possibility of movement along the supporting pipe, and the lower one is rigidly fixed.

The problem in the barrier for grouting mortar is solved due to the fact that in the barrier located around the supporting pipe containing the Central passage channel with many radial holes intersecting the Central channel for the exit of grouting mortar, consisting of folding material and associated supporting structures, providing a radial opening of the barrier and holding it in the open position, the structures providing the opening of the barrier are pivotally connected at one end to the carrier pipe, and the other ends in the open position of the barrier are in contact with the wall of the well, structures that ensure that the barrier is held in the open position, are connected at one end to the carrier pipe, and with other ends, to hold the barrier in the open position, the lower level of the barrier being lower radial holes, and held in a closed position by detachable slings twisted around the barrier, according to the invention, the barrier material is made in the form of a hollow shell closed around a pipe for the volume of grouting mortar, with the upper neck of the shell fixed to the supporting pipe with the possibility of movement along the supporting pipe, and the lower neck of the shell fixed to the supporting pipe motionless, holes are made in the upper part of the shell that provide hydraulic connection of its internal volume with the surrounding space, auxiliary the structures that provide the opening of the barrier are made in the form of a flexible frame, consisting of multi-link tapes, in the closed position of the barrier covering the shell, with for connecting it with the carrier tape tube, and its links with each other, the hinges are used, the shell through the flexible plate is fixed to the frame, the structure holding the barrier in an open position, are designed as rods or straps.

In the particular case of execution, multi-link tapes in the closed position are held together by twists of wire or any other knitting or fixing material.

In addition, the plates that press the shell to the flexible frame can be fastened with rivets, bolts or electro-rivets, as well as in any other way that ensures the reliability of the fastening.

The claimed inventions are presented in the following drawings: figure 1 schematically shows the inventive device in the closed position during the descent into the technical column; figure 2 - device with an open barrier in a place selected for the installation of a cement bridge; figure 3 is a view a in figure 1; figure 4 is a view of B in figure 2; figure 5 is a view of D in figure 4; figure 6 is a view In figure 2; Fig.7 is a view of G in Fig.2.

Figure 1, the barrier 1 for the cement slurry is shown during the descent into the well 2, which contains the barrel 3 and the technical column 4, cemented in it. The barrier 1 is shown in the closed position 5 in FIG. 1 and schematically shown in the open position 6 in FIG. 2 at a location selected to create a cement bridge, which can be determined by a cavernogram or other geophysical method for exploring wells. The barrier 1 contains a folding shell 7, which in the closed position 5 of the barrier 1 is in a folded position 8 and laid around the carrier pipe 9. In figure 2, the shell 7 is shown in the open position 10. The upper neck 11 of the shell 7 is mounted on a movable sleeve 12 with collars 13 (Fig. 7) by turns of the knitting wire 14. At the same time, the upper edge 15 of the neck 11 is turned downward, fits the turns of the knitting wire 14 and secured by the second row of the knitting wire 16 or in any other way so that the overall dimension allows free passage through pecifications column 4.

Outside, the sheath 7 is covered with multilink bands 17 fixed to it, which are connected to each other in the closed position 5 (Fig. 3) by means of a wire 18 or any other knitting materials, twisted 19. In this case, the wire 18 is used to protect against damage during lowering into the well laid between the plates 20 (Figs. 4, 5) constituting multi-link tapes 17, interconnected by hinges 21, and a sheath 7, which is pressed against the multi-link tapes 17 by the inner plates 22. In this case, the plates 22 are pressed against the plates 20 by rivets 23 or any other spo by itself (e.g. bolts).

A centralizer 25 is attached to the lower part 24 of the carrier pipe 9, a funnel 26 is located at the lower end of the carrier pipe. The carrier pipe is connected to the centralizer 27 at the top, which, in turn, is connected to the pipe string 28, while the diameters of the centralizers 25 and 27 exceed the transverse dimensions of the barrier 1 in the folded position 5. Between the support pipe 9 and the centralizer 25, a check valve 29 is installed.

The multi-link tapes 17 are radially mounted on the carrier pipe 9 by means of hinges 30 and can freely rotate around axes 31, which are fixed in hinges 30 by any known method (for example, lock washers or flaring). The lower neck 32 of the sheath 7 (Fig. 6) is fixed on the groove 33 made in the lower part of the carrier pipe 9 by turns of the knitting wire 34. In this case, the free part 35 of the neck 32 is turned down onto the turns of the wire 34 and tied on top by turns of the knitting wire 36 or any in another way, so that the overall size of the layout allows you to freely pass through the technical column 4. In the upper part of the shell 7 there are one or more holes 37 (Fig.2), providing hydraulic connection of its internal volume with the surrounding space by society. A bracket 38 is placed on the supporting pipe 9, on which flexible rods or slings 39 are fixed, the lower ends of which 40 are fixed on the multi-link tapes 17 and hold them in the open position 10.

Above the groove 33, radial holes 41 are made on the supporting pipe 9, which hydraulically communicate with each other the inner cavity 42 formed by the sheath 7, the central passage channel 43 of the carrier pipe 9 and through it the central passage channel 44 formed by the pipe string 28.

The method of plugging a well with a bridge is as follows.

Before the start of grouting, the spatial characteristics of the well 2 are determined in the place chosen for the bridge installation before the barrier 1 for cement slurry is lowered into the well 2, the dimensions of the barrier are selected so that it interacts with the well 2 in the place chosen to create the bridge . The barrier 1 contains a folding material in the form of a hollow shell 7 with a volume for grouting closed around the carrier pipe 9, and a plurality of shell-holding structures (keys 17, 39) connected at one end to the carrier pipe 9 and holding the shell 7 in the open position 10. Then, centralizers 25, 27, the diameters of which exceed the transverse dimensions of the barrier in the folded position, are connected to the support pipe 9 above and below the barrier 1, the support pipe 9 is connected to the pipe string 28 and the whole structure is lowered to the place chosen for installation hundred in an uncased portion of the wellbore 2, while retaining the barrier 1 in a closed position prior to and during the descent of the barrier at a selected location. The grouting mortar is displaced through the pipe string 28 and the supporting tube 9, moving the barrier 1 from the closed position to the open 10 by forcing the grouting mortar to completely fill the volume of the sheath 7, leading to its contact with the wall of the uncased part of the well 2 around the entire perimeter. At the same time, the pipe string 28 interconnected, the support pipe 9 with centralizers 25, 27 and the barrier 1 form a production string.

As cement slurry, for example, cement can be used.

A device for plugging a well works as follows.

The barrier 1 assembled on the surface around the carrier pipe 9 in the closed position 5 with centralizers 27 and 25 attached to the carrier pipe 9 from above and below is installed in the lower part of the pipe string 28. A non-return valve 29 is mounted between the lower centralizer 25 and the carrier pipe 9, and below the centralizer 25, a receiving funnel 26 is installed. During descent, the entire arrangement slides inside the technical column 4 and rests on centralizers 25 and 27, which thereby protect the barrier 1 from damage. Open check valve 29 provides free circulation of fluid. The descent of the barrier 1 is carried out to the design depth. After completion of the descent, the check valve 29 is closed, and cement slurry is supplied from the wellhead (not shown) by a cement pump (not shown) to the central passage channel 44 of the pipe string 28, which passes through the central passage channel 43 of the support pipe 9, from where through the radial holes 41 enters the internal cavity 42 of the shell 7, gradually filling and inflating it.

Under the action of bursting pressure, the twists of the knitting wire 19 are successively torn from the bottom up, gradually ensuring the full opening of the barrier 1. The openings 37 in the upper part of the sheath 7 create the necessary hydraulic resistance, which helps to completely fill the inner cavity 42 of the sheath 7 with cement mortar. In the process of opening, the multi-link tape 17 reaches the walls of the open bore 3 in the well 2, adjoins them, providing a smooth and dense pressing of the shell 7. The barrier 1 is wedged out in the well 2, and with the further injection of the cement mortar, the pipe string 28 is sealed and of high quality insulation. After the cement mortar has hardened, the cement cup formed in the central passageways 44 and 43 of the pipe string 28 and the carrier pipe 9, respectively, is drilled, and the check valve 29 is simultaneously destroyed. Thus, the formed production string, consisting of a string of pipes 28, a supporting pipe 9 with a barrier 1 and centralizers 25 and 27, is ready for operation. Funnel 26 subsequently provides trouble-free descent and lifting of the necessary downhole equipment.

Thus, the use of the proposed method will significantly simplify the process of plugging the uncased part of the well, since, unlike the prototype, the following steps are excluded: the destruction of the carrier pipe, the subsequent lowering of the production string and re-plugging of the well. At the same time, the quality of well plugging, even with a complex profile, only increases due to the use of devices having high reliability with relative simplicity of design, which avoids damage to the device during tripping and unauthorized overflowing of grouting mortar from the barrier.

Claims (8)

1. The method of plugging the well with the creation of the bridge, which consists in determining the spatial characteristics of the well in the place chosen to create the bridge, using a grouting barrier consisting of folding material and supporting structures holding it, and choosing the dimensions of the barrier so that it in the open position interacted with the wall of the uncased part of the well along the entire perimeter in the place chosen to create the bridge, determine the volume of the cement slurry displaced required to create a bridge, fix the barrier along the radius to the supporting pipe, equipped with radial holes for the cement slurry to exit into the cavity of the barrier, attach the supporting pipe with the barrier to the pipe string, lower the barrier in the closed position on the pipe string to the place chosen to create the bridge in the uncased part of the well, grouting is displaced down the pipe string and the carrier pipe to trap it with a barrier until a bridge is formed, characterized in that before lowering into the well, they are connected to the carrier pipe above below the barrier, centralizers whose diameters exceed the transverse dimensions of the barrier in the folded position, use the barrier material in the form of a hollow shell with a volume under the grout closed around the carrier pipe, while moving the barrier from the closed position to the open provide forcing the grouting mortar until the shell volume is completely filled, and interconnected pipe string, a supporting pipe with centralizers and a barrier form a production string. 2. The method according to claim 1, characterized in that cement slurry is used as the grouting mortar. 3. A device for plugging a well, which includes a pipe string with a central passage for supplying grout, connected in series and lowered through the technical column of the well, the pipe string having a length sufficient to reach the uncased part of the well below the technical string, carrying a pipe with a central passage channel, connected to the central passage channel of the pipe string, and radial openings for the exit of cement slurry, radially connected to the supporting pipe barrier for grouting mortar, consisting of a folding material and supporting structures that open the barrier and keep it in the open position, while the lower level of the barrier is below the radial holes of the carrier pipe, characterized in that it contains at least two centralizers mounted on the carrier pipe on both sides of the barrier, the diameters of which are larger than the transverse dimension of the folded barrier, the barrier material is made in the form of a hollow shell provided with holes in the upper part, providing hydraulic connection of its internal volume with the annular space, with the volume closed around the supporting pipe, in the open position of the barrier completely filled with cement slurry and in contact with the wall of the uncased part of the well along its entire perimeter, and the pipe string carrying the pipe with centralizers and a barrier form a production string wells. 4. The device according to claim 3, characterized in that it contains a check valve located on the carrier pipe below or above the lower centralizer. 5. The device according to claim 3, characterized in that the shell is attached to the carrier pipe by the upper and lower mouths, the upper neck being fixed with the possibility of movement along the supporting pipe, and the lower one is rigidly. 6. A cement slurry barrier located around a carrier pipe containing a central passage channel with a plurality of radial openings intersecting the central channel for grouting mortar consisting of folding material and auxiliary structures connected to it, providing a radial opening of the barrier and keeping it open position, and structures that provide the opening of the barrier, one ends pivotally connected to the carrier pipe, and the other ends in the open position, the barrier and in contact with the wall of the well, structures that ensure that the barrier is held in the open position, are connected at one end to the carrier pipe, and others are connected to structures that hold the barrier in the open position, with the lower level of the barrier located below the radial holes of the carrier pipe and held in closed the position of detachable slings twisted around the barrier, characterized in that the barrier material is made in the form of a hollow shell with a volume under the grout closed around the carrier pipe moreover, the upper neck of the shell is fixed on the supporting pipe with the possibility of movement along the supporting pipe, and the lower neck of the shell is fixed on the supporting pipe motionlessly, holes are made in the upper part of the shell providing hydraulic connection of its internal volume with the surrounding space, auxiliary structures ensuring the opening of the barrier, made in the form of a flexible frame, consisting of multi-link tapes, in the closed position of the barrier covering the shell, moreover, to connect the tapes to the carrier pipe, and its links between each other, hinges are used, the shell by means of plates is fixed on a flexible frame, the structures holding the barrier in the open position are made in the form of rods or slings. 7. The barrier according to claim 6, characterized in that the multi-link tapes in the closed position are held together by twists of wire or any other knitting or fixing material. 8. The barrier according to claim 6, characterized in that the plates pressing the shell to the flexible frame are fastened with rivets, bolts or electro-rivets, as well as in any other way that ensures the reliability of the fastening.

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