Patent ID: 12234953

DESCRIPTION OF EMBODIMENTS

This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing a currently preferred embodiment of the invention. Like numbers refer to like features throughout the drawings.

The description and drawings merely illustrate the principles of the present invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the present invention and are included within its scope. Furthermore, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the present invention and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions.

In the present invention, expressions such as “comprise”, “include”, “have”, “may comprise”, “may include”, or “may have” indicate existence of corresponding features but do not exclude existence of additional features.

FIG.1illustrates schematically an exemplary embodiment of a device100for measuring a conduit10being arranged in a subterraneous environment.

The conduit10illustrated inFIG.1is a conduit for transporting fluids such as water, oil or gas. Such a conduit is also referred to as a pipeline. The conduit10is often arranged subterraneously as illustrated inFIG.1and is surrounded by an insulator layer10′ to protect the conduit10from corrosion. The insulator layer10′ may be a coating applied to the peripheral surface of the conduit10or another protective surface layer, such as a cathodic protection. In order to illustrate the principles of the invention the insulator layer10′ is substantially enlarged.

The device100for measuring the conduit10illustrated inFIG.1comprises a mounting unit110, a first electrode120, a second electrode130and a measurement instrument140. The mounting unit110is configured to be arranged on a surface of the conduit10, particularly an outside surface of the insulating layer10′. The outside surface of the conduit10or the outside surface of insulating layer are interchangeably used in the context of this description, unless explicitly stated to the contrary. The mounting unit100is further configured to create an enclosure against the surface of the conduit10. In the context of this description, the enclosure is an area delimited by the mounting unit110and the surface of the conduit10. However, the enclosure also refers to a portion of the mounting unit110as will be elaborated with respect toFIG.3. The mounting unit110contains the first electrode120in the enclosure and is configured to form a dielectric between the first electrode120and the environment E. Although the mounting unit110thus electrically insulates the first electrode120from the environment E, an electric permittivity thereof influences an impedance value as will be illustrated here below. The second electrode130is configured to be arranged at a distance of the surface of the conduit10′ and at a distance of the first electrode120. The second electrode130is intended to be in contact with the environment. Put differently, the second electrode130is arranged such that it is at least partially exposed to the environment. The second electrode130may also be entirely exposed to the environment E, as is illustrated inFIG.1. The measurement instrument140is configured to determine a value which is representative of an impedance between the first electrode120and the second electrode130. As described here above, the mounting unit110forms a dielectric between the first electrode120and the environment E and thus also between the first electrode120and second electrode130. Even though the environment E is at least partially conductive because of the presence of moisture and ions, the first electrode120and second electrode130form the two poles of a capacitor. The impedance between the first electrode120and second electrode130comprises a plurality of components. A first impedance component C1A+C1B of the plurality of components is primarily determined by the dielectric which is formed by the mounting unit110and/or the surrounding environment situated E between the first electrode120and second electrode130. The first impedance component C1A+C1b is relatively constant because the first impedance component comprises a first impedance subcomponent C1A and a second impedance subcomponent C1B illustrated as capacitive symbols inFIG.1for illustrational purposes. The first impedance subcomponent C1A is primarily determined by the dielectric characteristics of the mounting unit110and does substantially not change. Particularly because the resistance and the reactance of the mounting unit110are constant, barring any wear and tear to the mounting unit110. The second impedance subcomponent C1B is determined by the permittivity of the surrounding environment E. Because changes to the composition of the environment E are limited, if any, for example the composition of earth surrounding the mounting unit110in a subterraneous environment does not change substantially, the reactance and resistance thereof remains substantially constant. Since neither the first nor the second impedance subcomponent of the first impedance component C1A+C1B changes, the first impedance component C1A remains substantially constant. The second component C2A+C2B is substantially determined by the dielectric which is formed by the insulator layer10′ and the surrounding environment E. Particularly, the insulator layer10′ determines a first impedance subcomponent C2A and the environment determined a second impedance subcomponent C2B of the second component C2A+C2B. The second impedance subcomponent C2B of the second component C2A+C2B is similar if not identical to the second impedance subcomponent C1B of the first impedance component C1A+C1B. When the conduit is good condition, the impedance formed by the plurality of components is known and constant. However, when moisture is present under or in the insulator layer10′ or corrosion is formed on a surface of the conduit10the impedance of the insulator layer10′ or the conduit underneath the insulator changes. Particularly, the first impedance subcomponent 2CA will change due to the moisture or corrosion because the impedance of the insulator layer changes, which causes a change in the phase measurement and a change in the amplitude measurement. This change in the value of the impedance indicates degradation of the surface layer of the conduit, for example due to corrosion, or indicates the presence of moisture in the insulator. The device100thus allows to accurately detect corrosion and/or moisture, and is also easy to use and cost-efficient. The other impedances subcomponents C1A, C1B, C2B (shown in a simplified model inFIG.1) will also influence the measurements, but a change of the measured value will be representative of a degradation of the surface layer. The measurement instrument140may comprise an electrochemical impedance spectroscopy measurement instrument or any other AC impedance measurement. Using such a measurement, the phase and amplitude of the impedance is obtained in function of the frequency. Also other AC or DC measurement instruments are possible as long as it is possible to determine a value which is representative of the impedance between the first electrode120and second electrode130underneath said portion of the insulator2.

Preferably, the first electrode120and/or the second electrode130are at least partially manufactured from a corrosion-resistant material such as stainless steel, galvanized steel, aluminium or graphite. In this way, the first and second electrode are more resistant to corrosion.

FIG.2illustrates schematically an exemplary embodiment of a device for measuring a conduit10being arranged in a submerged environment.

The conduit10′ is illustrated as a submarine communications or power cable which may contain a group of electrical conductors and/or fiber optics that carry electric power, video, and/or data signals between two locations.

FIG.2illustrates that the measurement instrument140may be arranged outside of the environment, for example on the surface of the water.

The device10ofFIG.2further illustrates that the second electrode130is preferably integrated in the mounting unit110. In this way the distance between the second electrode130and the first electrode120is reduced. The device100can thus be fabricated more compactly. Also, when the second electrode130is integrated in the mounting unit110, the first impedance component C1A no longer comprises a second impedance subcomponent. Only the known first impedance subcomponent C1A is present. The influence of the surrounding the environment is reduced in this way which further increases the accuracy of the device100.

Moreover,FIG.2illustrates that the enclosure formed by the mounting unit110may be intended to encompass a portion of the environment E when the mounting unit is arranged on the surface of the conduit10. An advantage thereof is based on the insight that conduits are available in all shapes and sizes. Ensuring that the first electrode120snuggly fits to the peripheral surface of the conduit10′ is difficult. An advantage of encompassing a portion of the environment E is that the environment for example dirt or water is conductive. Also, the environment, particularly the aqueous environment, is malleable. The encompassed portion of the environment will fill the recess, forming a conductive layer of contact between the first electrode120and the peripheral surface of the conduit10′. In this way, the first electrode120is electrically connected to substantially the entire portion of conduit which the enclosure covers. Put differently, the environment encompassed by the enclosure forms a part of the first electrode120.

In order to fix the mounting unit110on the surface of the conduit10′ fixations means may be used. The fixation means may be a submarine pressing the mounting unit110on the surface of the conduit. The fixation means may also be a clamp configured to clamp the mounting unit on the surface.

FIG.3schematically illustrates a device100having an integrated second electrode130and an enclosure according to an exemplary embodiment.

The device100illustrated inFIG.3comprises at least one peripheral wall111having a lower edge112intended to be in sealing contact with the surface of a conduit (not shown). The peripheral wall111forms the enclosure containing the first electrode120. The lower edge112seals the enclosure from the environment. In this way short-circuit measurements directly between the first and second electrode without any dielectric in between are substantially avoided, further improving the accuracy of the device.

According to the illustrated exemplary embodiment the enclosure is further delimited by an upper wall114joining the peripheral wall111. Additionally, the first electrode120is a plate arranged against or in the upper wall114. The upper wall114seals the enclosure entirely, such that the enclosure is sealed from the environment further improving the accuracy of the device. The first electrode120being a plate has the advantage that a surface area of the first electrode120is substantially large. This facilitates the determining of the impedance value. Moreover, in comparison with the embodiment illustrated inFIG.1, the enclosure containing the first electrode120is configured such that an open space113is retained even when the first electrode120is contained. In this way the advantages of a platelike electrode and encompassing the environment are combined.

The second electrode130is preferably arranged at a peripheral side of the mounting unit110. In this way, the second electrode130is exposed to the environment in a relatively simple way. The second electrode130may be arranged at any peripheral side of the mounting unit110.FIGS.2and3illustrate different locations where the second electrode may be arranged.

The enclosure may made of an elastically compressible material. In this way, the mounting unit110as well as the enclosure are easily installable on the conduit. The elastically compressible material will be correspondingly shaped according to the respective conduit it is arranged on. According to a preferred embodiment the mounting unit is entirely made from an elastically compressible material. More preferably, the elastically compressible material is an elastomer. More preferably, the elastomer is one or more selected from the group of siloxane-based elastomers, urethane-based elastomers, acrylate-based elastomers.

FIG.4illustrates an exemplary embodiment of a device100for measuring a conduit wherein the mounting unit110may be further configured to accommodate the measuring instrument140. In this way, the device100is formed in an integrated and easily transportable way.

The device100may further comprise a controller150which is configured to analyse the presence of moisture and/or condensation in the conduit and/or advance of corrosion of the conduit on the basis of the value determined by the measuring instrument. In this way, the device100is further designed to be stand-alone. The controller150may be integrated in the mounting unit110or may arranged in a remote location or device, for example a ship.

FIG.5illustrates an exemplary embodiment of a controller150being arranged in a remote location.

In such an exemplary embodiment the measuring instrument140may be configured to transmit the determined value wirelessly through the environment. An advantage hereof is based on the insight that the conduits are often arranged at difficult to reach positions, for example on the ocean bed or subterraneously under a road. By providing the device100with a measuring instrument140which is configured to transmit the determined value wirelessly through the environment, the device100can be arranged on the conduit, covered by the environment and still transmit the determined value without substantial effort. De device100is for example simultaneously submerged when arranged the conduit in the ocean or when the conduit is arranged in the ground.

FIG.6illustrates an exemplary embodiment of a device100further comprising a connection interface160.

The connection interface160is arranged above or near the surface of the submerged or subterraneous environment E and comprises a connection cable161extending from the connection interface to the measuring instrument. More preferably, the connection cable161is an optical fibre cable for fibre-optic communication of the determined value. In this way, information determined by the device can be measured from outside of the environment. For example, a user may arrive on-site, connect a computer to the connection interface and input the value representative for the impedance to his or her computer. The connection interface may comprise at least one of the following power supplies: a wire supply, an energy yield supply and a battery supply. A very long lifespan of the measurement can be obtained with a wire supply, while a battery supply can be inexpensive and simple to install. An energy yield supply can be very energy-efficient and autonomous, which can be advantageous in the case of conduits which are difficult to reach (such as long-distance conduits). The connection interface160may comprise an antenna configured to transmit the determined value wirelessly, for example to a monitoring system. In this way the convenience of use can be increased. In addition, central control can be made possible.

FIG.7illustrates a preferred embodiment wherein the device100comprises a plurality of mounting units110.FIG.7illustrates two mounting units110which are arranged on a surface layer of the conduit. By arranging a plurality of mounting units the area in which moisture or corrosion can be detected can be increased in size. A similar effect may be achieved by arranged two first electrodes in a single mounting unit (not shown). The plurality of mounting units110may share a common second electrode, as illustrated inFIG.7. Alternatively, the measuring instrument may determine a value which is representative of an impedance between the first electrode of one of the mounting units and another first electrode of another mounting unit110(not shown). It will be clear that more than two mounting units110may be arranged on the surface110.

Although not illustrated in the figures the invention further relates to a method for measuring a conduit being arranged in a submerged or subterraneous environment is provided. The method comprising moving a mounting unit110, a first electrode120and a second electrode130through the environment. This may be done when laying the conduit subterraneously or in a submerged environment. Moving the mounting unit through a dirt environment is considered similar to moving the mounting unit through an aqueous environment. Moving the mounting unit through an aqueous environment may be done using submarines or submarine type devices.

The mounting unit110is arranged on a surface of the conduit thus creating an enclosure against the surface. The first electrode is contained in the first enclosure such that the enclosure forms a dielectric between the first electrode and the environment. The second electrode is arranged at a distance of the surface and at a distance of the first electrode, wherein the arranging of the second electrode comprises arranging the second electrode in contact with the environment. Finally, a value which is representative of an impedance is determined between the first electrode and the second electrode. The arranging of the mounting unit may comprise encompassing a portion of the environment in the enclosure. This is particularly useful in submerged environments. Moreover, the arranging of the mounting unit may further comprise pressing or clamping the mounting unit on the surface. This may be performed for example using a submarine robot or the like, or clamping the mounting unit to the conduit when the conduit is arranged in the ground or water.

It is noted that the inventor has found that, where the above illustrated embodiments have been described in combination with submerged or subterraneous conduits, the device can also be used to determined moisture ingress in roof insulation. In such an embodiment, the first electrode is arranged on the insulation, for example mineral wool. The second electrode may be formed by an earthing system which is typically readily available in houses or building in general.

It should be noted that the above-mentioned exemplary embodiments illustrate rather than limit the present invention and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word “comprising” does not exclude the presence of elements or steps not listed in a claim. The word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements. The usage of the words “first”, “second”, “third”, etc. does not indicate any ordering or priority. These words are to be interpreted as names used for convenience.

Whilst the principles of the present invention have been set out above in connection with specific embodiments, it is to be understood that this description is merely made by way of example and not as a limitation of the scope of protection which is determined by the appended claims.