RU176204U1 - FLEXIBLE EXTENDED HOLLOW DESIGN - Google Patents

Abstract

The technical solution relates to the field of production and operation of flexible long structures, for example, corresponding to GOST 30723-2006 and allows quickly and with a given accuracy to determine the place of leakage, while automatically isolating it from the spread of fluid in the cavity between the two shells. Technical result - reduction (narrowing ) zones of guaranteed detection of damage to any of the shells, which led to the formation of a leak, as well as to the possibility of visual determination of such a place by deformation of the outer shell. Simultaneously with the reduction of the zone of guaranteed detection of damage, the zone of water penetration along the length of the flexible extended hollow structure is automatically isolated (limited) due to compression of the leak zone and thereby to plugging of the leak site. The technical result is achieved by the fact that the flexible extended hollow structure contains an internal hollow metal shell , the outer shell of a polymeric material installed with a gap relative to the inner shell, foamed heat-insulating material, placed in the gap between the shells, ring centering bearings placed in the gap concentrically to the metal shell along its length, and conductors of the online remote control system located along the length of the hollow structure in the gap between the shells, and the ring centering bearings are made in the form of a matrix of polymer material with embedded into it a swellable filler with the possibility of isolating the moisture-containing volume between the centering supports adjacent to the leakage zone.

Description

The technical solution relates to the field of production and operation of flexible long structures, for example, corresponding to GOST 30723-2006, having an internal hollow metal shell, an outer shell of a polymeric material installed with a gap relative to the inner shell, foamed heat-insulating material placed in the gap between the shells, ring centering bearings placed in the gap concentrically to the metal shell along its length, and conductors of the operational remote control system, located the length of the hollow structure in the gap between the shells.

Known hollow long structures with an inner shell and an outer shell, the cavity between which is filled with heat-insulating material, in which an electrical conductor connected to a direct current source is connected, connected to a current measuring device. The other conductor is spirally and grounded. A change in the magnitude of the electric current occurs with a change in conductivity (or electrical resistance) due to wetting of the medium in which the electrical conductors are located. A change in the current value indicates a leak in the structure, the place of which should be determined (EP 2287587 A2, 08/05/2010).

The closest known is a flexible load-bearing polymer hollow structure, in the walls of which are reinforcing elements in the form of metal wires or tapes, laid by at least two layers having a winding angle from 15 ° to 75 ° to the axis of the structure, and longitudinally in the wall of the hollow structure or at least one continuous layer of metal foil or tape is placed, with power and / or signal conductors additionally laid in the wall of the structure (RU 119430 U1, 08.20.2012).

Common disadvantages of the known devices are the complexity and inaccuracy of determining the actual leakage location when an electrical device detects the leakage fact, which leads to an increase in the laboriousness and time of work on finding the leakage location and elimination of its causes, since the known structures have no restriction of the spreading fluid in the cavity between shells, and a change in conductivity (or electrical resistance) occurs over the entire extended area where the liquid penetrates.

Thus, the main unsolved problem of these devices arises from the wetting of thermal insulation, which is performed, as a rule, from polyurethane foam (PUF). Water penetrates into the structure, for example from the outside, as a result of damage to the outer shell or destruction of the coupling or due to poor welding quality of steel shells (pipes) or their corrosion. To detect liquid (water), an alarm system with conductors in thermal insulation is used. Since thermal insulation has low water absorption, water moves inside the structure through cracks, cavities, etc. In this case, the alarm is triggered with a significant delay when the water has already passed through cracks, cavities, etc. tens of meters.

The objective of this technical solution is to create a device with a flexible long hollow structure, which allows quickly and with a given accuracy to determine the place of leakage, while automatically isolating it from the spread of fluid in the cavity between the two shells.

The technical result of this technical solution is to reduce along the length of the zone of guaranteed detection of damage to any of the shells, leading to the formation of leaks, as well as to the possibility of visual determination of such a place by deformation of the outer shell. Simultaneously with the reduction of the zone of guaranteed detection of damage, the zone of water penetration along the length of the flexible extended hollow structure is automatically isolated (limited) by compressing the leak zone and thereby plugging the leak.

Disclosure of a technical solution.

These results are achieved by the following essential features, each of which is necessary for this, and all together are sufficient: - a flexible long hollow structure contains an internal hollow metal shell, an outer shell of polymeric material installed with a gap relative to the inner shell, a foamed insulation material placed in the gap between the shells, the ring centering bearings placed in the gap concentrically to the metal shell along its length, and conductors of the operational dist control centers located along the length of the hollow structure in the gap between the shells, and the ring centering supports are made in the form of a matrix of polymer material with a swellable filler embedded in it, making it possible to isolate the moisture-containing volume between the centering supports adjacent to the leakage zone.

The technical result can be enhanced by the fact that:

- a thermoplastic polyolefin is used as a polymer matrix;

- sodium acrylate and / or bentonite clay and / or polyacrylamide are used as the swellable filler;

- swelling filler is introduced in an amount that provides the possibility of local deformation of the outer shell;

- ring centering bearings are made with the possibility of creating a pressure of at least 10 atm on the outer shell of a polymeric material and compressing the foamed heat-insulating material in the leak zone;

- ring centering supports are installed with the possibility of compression placed between them moisture-containing foamed thermal insulation material;

- ring centering supports contain a migrating corrosion inhibitor - the widespread IFHRAN 80 or MCI 2020 distributed in a polymer matrix, in this case, in the form of a water-soluble powder or granules;

- ring centering supports contain salts, the solution of which is an electrolyte that increases electrical conductivity in the zone of water inflow;

- ring centering bearings are made in the form of rings of constant or variable cross-section with protrusions or cuts on the outer perimeter.

In FIG. 1 is a sectional perspective view of a flexible extended hollow structure;

in FIG. 2 - ring centering support (option with narrowing to the longitudinal axis of the structure);

in FIG. 3 - ring centering support (option with expansion to the longitudinal axis of the structure).

Flexible extended hollow structure contains an inner hollow metal shell 1, the outer shell 2 of a polymeric material. The shells 1 and 2 are installed with a gap relative to each other, in which a foamed heat-insulating material is placed 3. The ring centering supports 4 are placed in the gap concentrically to the metal shell 1 along its length. As the material of the centering supports, a thermoplastic polyolefin is used, which is a polymer matrix into which a swellable component is introduced — a filler distributed in the matrix body 5 — sodium acrylate, and / or bentonite clay, and / or polyacryl amide, or another, comparable in manifestation in a similar medium properties. In addition, the matrix may contain a migratory corrosion inhibitor, for example, IFHRAN 80 or MCI 2020 or similar properties shown in the aquatic environment. Corrosion inhibitor is used in powder or granular form. An inhibitor is a component of the system. By saturating the swellable components with water, the matrix system becomes porous. When interacting with water, the inhibitor dissolves and enters the aquatic environment in the area of the resulting leak to prevent corrosion of the metal shell. The conductors 6 of the operational remote monitoring system are located along the length of the hollow structure in the gap between the shells 1 and 2. In the presence of water (electrolyte), conductivity occurs in the medium in which the conductor is located, and the corresponding signal about the presence of water is transmitted to the operator. The annular centering supports 4 are made to swell due to their described design to the possibility of local deformation of the outer shell 2 and providing isolation of the moisture-containing volume between the adjacent centering supports in the leakage zone.The ring centering supports 4 are installed with the possibility of crimping the moisture-containing foamed heat-insulating material placed between them. The ring centering supports 4 are made with the possibility of creating a pressure of at least 10 atm on the outer shell of a polymeric material and compressing the foamed heat-insulating material in the zone of water inflow, which ensures a decrease in water flow. Ring centering supports 4 may contain known salts, the solution of which is an electrolyte that increases electrical conductivity in the zone of water inflow. In addition, the ring centering supports 4 contain a water-soluble corrosion inhibitor. The ring centering bearings 4 can be made in the form of rings of constant or variable cross-section with protrusions or cuts on the outer perimeter to increase the effect of compression.

In case of leakage due to damage to the outer shell 2 or metal shell 1, water spreads through cracks and voids, etc. foamed heat-insulating material (for example, in polyurethane foam - PUF), the water swelling of the centering support blocks the access of water through them. With further compression of the foamed insulation material as a result of the swelling of the centering supports, its density increases - with an increase in density, the water absorption of the foamed insulation material decreases, and the leakage zone is isolated. Damage zones are detected over a shorter length of the extended structure due to the electrical signal along the conductor and can be clarified by measuring the local change in the diameter of the outer shell in the area of swollen centering supports.

Implementation example.

Centering supports are made of polyethylene or a polymer composition based on polyethylene and polypropylene. Such a material has the properties of swelling in water. The swelling centering support interacting with water due to the swelling ingredients included in the polymer matrix (selected, for example, from sodium acrylate, and / or bentonite clay, and / or polyacrylamide) compresses the heat-insulating material (the pressure at swelling is about 10 atm, the higher the density of the heat-insulating material - the lower its water absorption), closes cracks and cavities, etc. in it, which creates an obstacle to significant penetration of water along the axis of the pipeline. The electric alarm system will work faster due to the localization of the volume (the distance between the rings is 1 m) and the achievement in it of a smaller amount of liquid necessary for its operation. The place of violation of the integrity of the shell (internal or external) at this pressure can be determined by the radial deformation of the outer shell. Additionally, the powder or granules of a water-soluble corrosion inhibitor introduced into the polymer matrix, dissolving in water, prevent corrosion of the steel shell until the causes of leakage are eliminated, and also (forming pores when dissolving) improve the conditions for water to reach the mentioned swelling ingredients, thereby accelerating the swelling process. An inhibitor is a component of the system. Due to the swelling components, the system becomes porous, which contributes to the water dissolution of the inhibitor. When interacting with water, it dissolves and protects the metal shell in the area of the damaged area.

Claims (9)

1. A flexible long hollow structure containing an inner hollow metal shell, an outer shell of polymer material, installed with a gap relative to the inner shell, foamed insulation material placed in the gap between the shells, ring centering supports placed in the gap concentrically with the metal shell along its length, and conductors of the operational remote control system located along the length of the hollow structure in the gap between the shells, moreover, the centering ring supports in made in the form of a matrix of polymer material with a swellable filler embedded in it, with the possibility of isolating the moisture-containing volume between the centering supports adjacent to the leakage zone. 2. A flexible long hollow structure according to claim 1, characterized in that a thermoplastic polyolefin is used as a polymer matrix. 3. A flexible long hollow structure according to claim 1 or 2, characterized in that sodium acrylate and / or bentonite clay and / or polyacrylamide are used as the swelling filler. 4. Flexible long hollow structure according to claim 1, characterized in that the swellable filler is introduced in an amount that allows local deformation of the outer shell. 5. Flexible long hollow structure according to claim 4, characterized in that the annular centering bearings are made with the possibility of creating a pressure of at least 10 atm on the outer shell of a polymeric material and compressing the foamed heat-insulating material in the area of water inflow. 6. A flexible long hollow structure according to claim 1, characterized in that the annular centering supports are installed with the possibility of compression placed between them moisture-containing foamed thermal insulation material. 7. The flexible long hollow structure according to claim 1, characterized in that the annular centering supports contain a migrating corrosion inhibitor IFHRAN 80 or MCI 2020 distributed in a polymer matrix in the form of a water-soluble powder or granules. 8. A flexible long hollow structure according to claim 1, characterized in that the ring centering supports contain salts, the solution of which is an electrolyte that increases electrical conductivity in the zone of water inflow. 9. A flexible long hollow structure according to claim 1, characterized in that the annular centering bearings are made in the form of rings of constant or variable cross-section with protrusions or incisions along the outer perimeter.

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