JPS6396875A - Mesh electrode and clip used in formation thereof - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to anodes suitable for use in corrosion protection systems, particularly for reinforcing rods in concrete.
Regarding 2).

[Prior Art and Its Problems, αj Anodes used in corrosion protection systems are described, for example, in U.S. Pat. No. 4,520,929 (Stewart), 4+
No. 47L450 (Yaneke), No. 4,319,854 (Marzohii).

No. 4.255,241 (Coulomb), No. 4,267.0
No. 29 (Masarskiy), No. 3.868.313 (Gay), No. 3,789, 1.42 (Evans), No. 3.
No. 391.072 (Pearson), No. 3,254,063
No. 3,022,242 (Angusson), No. 2,053゜314 (Brown) and No. 1,
No. 842,541 (Comverland), British Patent Application No. N 1,394,292 and No. 2,046,789A9 Japanese Patent Application No. 35293/1973 and 4894
No. 8 71978 and European Patent Application No. 0.147.9
It is disclosed in No. 77. Mesh thunderstorms are especially suitable for preventing corrosion of concrete reinforcing bars. However, known mesh anodes were not sufficient.

(This is particularly difficult if the anode is applied entirely or partially, e.g. in the installation location on the surface of a reinforced concrete structure.) or Damage caused by physical failure at several points or by corrosion incidents can disconnect large areas of the anode from the power supply.

[Objective of the Invention 1 This invention was made to eliminate the above-mentioned problems, and an object of the present invention is to provide a corrosion prevention system that is easy to install and provides a stable corrosion protection function over a long period of time.

[Structure 1 of the invention] We fix the points of the same or different elongated electrodes to each other at the separated connection parts of the network formed by the electrodes, and provide electrical and electrical connections between the electrode parts at the connection parts. It has been found that these drawbacks can be overcome by the use of a resiliently deformable clip that provides a mechanical connection.

Although it is preferred to provide such a lip at each /Z connection of the mesh, it is not necessary. This clip initially provides a convenient and quick fixation method for elongated thunderstorms in the desired mesh structure. If no pond treatment (e.g. a layer of concrete placed directly or indirectly on the anode after the mesh has been installed) is employed to preserve the mesh structure, the clip will continue to perform this function. It might come true. If the anode is not damaged, this clip is not required to play any substantial electrical role in the action of the anode.

However, if the anode is damaged and current can no longer flow through the elongated electrode directly to all parts of the anode, this clip provides an alternative current path and the entire anode is virtually in working condition. Stay in. The fact that the clip deforms elastically not only helps to retain it effectively when the anode is flexible (which is preferred), but also if the deformation of the elongated electrode is caused by e.g. When deformed due to corrosion,
Provides good electrical connection during initial and subsequent operation. This is what if! S long electrode is made of conductive polymer (
This is preferred when the electrode contains, for example, carbon black, graphite, or other corrosion-resistant particulate fillers distributed within a polymer matrix, but the electrode is also enriched with resin, e.g. in the surface layer. This is particularly important when formed by melt extrusion (ie, the surface layer contains a relatively small proportion of filler). The pressure exerted by the clip on the electrode part is at least 0°01 ps
i(0, O(,107 kg/cm2), preferably at least 0.051 si(0,0035 kg/cm2),
However, in general, 10 psi (0.7 kg/cm2)
or less, preferably 5 psi (0.35 kg/a
m2) or less, for example 0.1 to Ipsi(0,
007 to 0.07 kg/cn+.

According to one aspect, the present invention provides a mesh electrode suitable for use as an anode in a corrosion protection system, the mesh electrode being arranged in a mesh configuration and having an elongated electrode or multiple electrodes connected to one another. one or more elongated electrodes having a number of spaced connections coupled to the electrodes; and (1) a plurality of clips, each clip having a connection between the electrode portions at one of the connections. providing mechanical and electrical connections, the electrical connections at each electrode section being at least 25
m+++2, preferably at least 50 mm2, particularly preferably at least 100 mm2, even more preferably at least 20 On+m2, the electrical contact area of which is greater than 20 On+m2, and this connection can be used if the size of the connected electrode parts is reduced. The clip is resiliently biased such that the target and electrical connections are maintained by the clip's elastic recovery.

In another aspect, the invention provides a method of forming such an electrode, the method comprising: (1) arranging one or more elongated electrodes in a desired mesh pattern; and (3) forming connections in the mesh. connecting the electrode portions at the connection portion by using a clip that is elastically deformable around the connection portion.

In another aspect, the invention provides a method for cathodic protection of reinforcing rods embedded in corrosive substrates, particularly concrete, which method comprises a potential difference between the substrate as a cathode and the above-mentioned mesh as an anode. including establishing.

In another aspect, the present invention provides a method of applying a reinforced concrete structure to cathodic protection of reinforcing bars, the method comprising fixing a mesh electrode as described above to the surface of the structure.

In another aspect, the invention provides a clip suitable for use in the manufacture of the above-described mesh electrode, the clip having at least two indentations, each indentation being comprised of a conductive material. , and adapted to receive an electrode portion and to be in electrical contact with the electrode portion over a surface area of at least 25 x 2, the exposed surfaces of which are electrically connected to each other. and [2] mechanical interconnection means for restricting movement between the recesses and maintaining said electrical contact by resilient biasing.

The recesses in the exposed conductive surface that contact the electrode portions need not be recesses throughout the surface; in one embodiment, the clip is constructed entirely of conductive polymer. However, with such a curved lip, it is not possible to simultaneously satisfy the desired characteristics of low resistance and high physical strength and elasticity. In another embodiment, therefore:
The clip is constructed of a conductive polymer and includes at least a portion of each recess, e.g., a bridging member between the recesses, and the remainder of the clip is comprised of a slightly conductive or non-conductive polymeric material. For example, it has a resistivity of 1 to 5 ohm-cm. In another embodiment, the electrical interconnection means is provided by a non-polymeric, corrosion-resistant material, such as foil, wire or wire, having at least an outer surface of, for example, niobium, titanium or stainless steel. Most of these metals are so expensive that it is impractical to construct the entire clip from these metals. Each recess and the bridge between the recesses is partially or completely coated with material, and the remainder of the clip is preferably made of a non-conductive material.
Constructed of a polymer that includes a resilient bias and provides the desired mechanical interconnection means. In all clips, a deformable, generally inelastically deformable, conductive material, such as conductive mastic or grease, may be used to improve the electrical contact between the clip and the electrodes. can.

[Example 1 The invention is illustrated in the accompanying drawings.

Third, in the following description of the invention with reference to the drawings, the various aspects illustrated in or described in connection with the individual drawings or drawings may be as broadly described herein. However, it should be understood that the present invention can also be applied to the three-body embodiment of the pond by any essential parts or appropriate modifications, whether shown or not.

The invention is particularly applicable to cathodic protection for concrete reinforcement, as shown in FIG.

FIG. 1 shows concrete 1 reinforced by reinforcing bars 2, which are partially exposed for illustration.

The electrode 3 as anode is placed on the surface of the concrete 1 and is provided with an upper M4, generally made of an electrically conductive material, in particular an ionized electrically conductive material. The upper layer 4 comprises concrete or cement, conductive concrete or cement, gypsum-based material or polymeric material.
A special example is concrete of Portland cement and asphalt concrete, or modified concrete of Portland cement (e.g. latex-1 is concrete with acrylic addition), which is connected by a power source 5 to an electrode 3 as an anode and a reinforcing rod 2 as a cathode. A potential difference is applied between.

This electrode 3 is preferably in the form of a mesh and is preferably flexible. The minimum dimension of the aperture (i.e., the shortest side of the aperture) in a mesh such as
, preferably at least 1 inch (2,5 cm), particularly preferably at least 2 inches (5,0 cm), more particularly preferably at least 4 inches (10,0 cm), particularly preferably at least 6 inches (15 cm). The maximum dimension of the opening (i.e., the longest side of the opening) is generally 48 inches (120 cm) or less, but no more than 24 inches (6
0 cm) or less, and in some applications up to 8 inches (
20cm) or less. Preferably, the shortest and longest sides of the aperture differ by a factor of about 3 or less, in particular by a factor of about 2 or less. The openings in the mesh can be of any shape, for example substantially square or substantially rectangular in shape. The size and shape of the apertures, including the special mesh, will generally be substantially the same, but may vary. A mesh is a structure in which closely spaced elements are interconnected, for example by integrating and looping these elements.
Alternatively, it refers to a simple arrangement of conductive clips connected by conductive clips. Generally, a given element may be connected to one or more adjacent elements, but this mesh does not require that.

The mesh is preferably 7 lexical, and the term 7 lexical as used herein refers to a circular fine mesh 12 inches (30 cm) in diameter along at least one axis, preferably two orthogonal pongees. around the diameter, preferably 6
This means that it can be bent at an angle of 180° around a circular inch (15 cm) without damage. This property results in very important advantages. That is, the mesh can be easily transported in rolls to the installation site and can be installed with minimal difficulty under a wide variety of different conditions.

In order to obtain such four flexibility, the electrode element 6 constituting at least a part thereof may be made flexible. The electrode elements 6 may be aligned in substantially orthogonal directions and may be flexible in one or both of these directions.

The flexibility, however, is due to or is enhanced by the structure of the electrode of elements. For example, the structure of the electrode elements and the way the elements are coupled to each other influences flexibility. In particular, we prefer that where clips are used to join electrode elements or points of elements, the clips allow some movement, for example rotational movement.

The electrode 3 illustrated in FIG. 2 includes a set of electrode elements 6 that are generally zigzag shaped. Each electrode element 6 is interconnected to adjacent elements by a clip 7 located at the top of each of the zigzag shapes. Even if element 6 itself is not flexible (if the zigzag depth is small), this electrode 3
It is clear that it is flexible if it can be wound around a minute parallel to the direction of the arrow. This flexibility can be achieved by making the clip 7 bendable or
This is due to the element 6 being able to rotate within the clip.

In FIG. 2, each element 6 is independent of all of the pond except for the clip 7. Therefore, if a desired substantially uniform electrical potential is required to exist over the entire surface of the electrode, clips 7 are required to obtain electrical interconnection between the elements. As shown, it is generally not necessary to provide clips 7 at all locations where they are applicable.

A different embodiment of a mesh electrode is shown in Figures 3A and 3B, in which one electrode element 6 is placed in a pair of loops 8a and 8b over the desired area to which the potential is applied. In FIG. 38, the clip 7 is positioned such that each of the loops is connected to another electrode section (generally an adjacent loop) at its distal end or in close proximity to this location. (“Distal portion” generally means furthest away from the point of attachment, and therefore in this specification, in relation to any loop, means the portion of the loop that is remote from the portion of these elements. (For example, attachments to adjacent loops form a point.)
In FIG. 3A, five clips 7 are used for nine loops (the number calculated assuming that loops 8 a and 8 b are separated), and the power source 5 is connected as shown in the figure. As long as both ends are supplied, no part of the electrode will be insulated even if any double cut occurs, as shown by the dotted line. Such double cuts may occur in practice, as the parts of the two electrode elements are close together in many places; 4fl scratches may occur, for example, due to road construction in the case of concrete pre-7. May. ,
The double cut shown by the alpha line will not insulate either of the electrodes shown, even if a voltage is applied to only one of the two ends, but the double cut will insulate some part of the electrode. There are several places like this. However, it can be seen that this problem can be avoided by using more clips. It is known that the number of clips achieving a preferred level of protection is five as shown, ie equal to the number of loops 8a.

In FIG. 3B, several novel aspects are shown,
A configuration of the mesh electrode and an arrangement in which a loop is provided;
and the use of a curved clip 7A.

This electrode element 6 comprises a number of loops 8a interconnected by sections 8c which are substantially straight over their entire length (in FIG. 3C the interconnections are curved or zigzag shaped).
and 8b. This top or pond section or each loop may be provided by an extension of the electrode element 6a or other bus 6b. In the illustrated embodiment, the loop 8a is connected to the electrode element 6
interconnected by an extension of a, and loop 8b is
They are interconnected by a separate bus 6b. The arrangement need not be this way; both sets may be provided by separate buses or by extensions of the electrode elements. Electrode element 6 (or bus)
One end of the element 6 is connected to the power source 1ft5, and the end (or trace bus) may also be connected to the power source 5 via the part of the element 6 near the first end, as illustrated by the clip 7b.

The third aspect shown in FIG. 3B is a curved clip 7a.
The rock IM is to help maintain the desired shape of the loops 8a and 8b.

These clips 7a, which will be illustrated in more detail in later figures, also serve to securely fix the electrodes to the deck of the bridge or other substrate for cathodic protection, and also to the loops. The means of electrical connections made between 8 a, 8 b and buses 6 a, 6 b serve to position the clip 7 .

In addition to the clip 7 connecting the loop and the bus, this clip 7 also provides an electrical connection between the interconnects 8C. As in the previous example, the clip 7 used
The number of redundancy is generally required.
It depends on the degree of y). In this text, "margin" means the extent to which the electrode elements 6 are accidentally separated while all (or desired locations) of the electrode elements 6 can be driven. The two interconnections 8C in each green in all of the configurations are interconnected by clips 7 at a distance X of approximately 20 feet or less, preferably 15 feet or less, and particularly preferably 12 feet or less. good. Connections may also be made between the bases of the interconnect. For a typical configuration, at least 10,
Preferably at least 20 clips 7 are used.

The number of clips used will depend not only on avoiding parts of the electrode being insulated, but also on the resistivity of the clips and the electrode element 6, and on the way the electrodes are energized, e.g. if a certain shape of bus is used. Depends on what you do. It is generally desirable for a substantially uniform potential to exist across the surface of the electrode, and this is facilitated by the use of multiple clips, greater than the desired number, to prevent insulating conditions. Alternatively, more clips may be provided closer together. The considerations discussed above are generally applicable to pond electrode structures, and the preferred designs of clips described below are applicable to these or pond electrode structures.

Figures 4-15 illustrate various clips, the first
Figures 3 and 14 show the clip in conjunction with the electrode element. Any of the various embodiments illustrated and discussed can be combined with any other clip, and the illustrated and discussed clips include conductive polymers and/or
*r electrical interconnection means (preferably at least two
5■2, more preferably at least 50III112
each two electrode elements contacting each other over a surface area of the electrode elements) and mechanical interconnection means (preferably by resilient biasing to limit movement between the electrode parts and maintain electrical contact). ing. When carbon black is used as a filler, the particle size is 0. II or less, especially 0.0 mm or less, at least 40%
, especially at least 50% carbon black. The pond fill material may include a fiber filler such as carbon fiber (generally up to 30%) with a fiber length of 6 mm or less, and graphite and metal oxides.

FIG. 4 shows a clip 7 with a groove in which a means 9, in particular a part of an electrode element, is located. The mouth of each groove is
Preferably, it is slightly smaller than the area receiving the electrode portion, so that the electrode snaps into the clip and does not come loose. In addition, the cross-sectional size of the groove 9 is
It is preferably slightly smaller than the electrode portion, so that some pressure is applied to the electrode portion. As a result, the clip, which preferably includes electrically conductive material, provides an electrical connection between the two electrode portions, which electrical connection is caused by a resilient force associated with the elasticity or resiliency of the clip and the small-sized groove. It is maintained by As a result, means for electrical interconnection and for mechanical interconnection are provided by the electrically conductive 9 resilient material. The clip preferably allows rotation of the electrode part and the electrode part and groove are therefore preferably substantially circular in cross-section. Each clip may have only two grooves, but more than one groove or four sections may be provided for pond applications.

Where the electrode part has an electrochemically active surface, a good contact is maintained between the contact part and the clip.
It is desirable to suppress chemical reactions at the tubes that come into contact with the clip. Good contact between the clip and the electrode section is
Rather than improving electrical contact, it reduces the chemistry of the electrodes (and the clip contacts) since electrolyte is prevented or prevented from reaching the contact surfaces. If desired, the contacting surfaces may be coated with some electrochemically inert material to maintain contact.

If the elastic clip (or electrode part) can compensate for a significant reduction in the size of the contact part and/or an increase in the size of the groove 9, the extent of such electrochemical action to be suppressed will be reduced.

The surface area of the groove (or the contact area of the pond) is preferably at least 25 a+m2, more preferably at least 5
0ml112, more preferably at least 610()■2
, especially at least 200 mm2, especially at least 300 mm2. The value chosen depends on the propensity of the materials in question to react and their resistivity.

Resistance of the clip (means the resistance imparted between the two electrode sections when the two electrodes are located in their respective grooves or otherwise properly located).

) is preferably 25 ohms or less, more preferably 15 ohms or less, especially 10 ohms or less, especially 5 ohms or less, more particularly 3 ohms or less. 2
Where two or more clips are connected in the same location with substantially no gaps between the clips, these values will be the resistances in their combined state.

Where the electrode is used as an anode, it is desirable that the clip not corrode or corrode at a moderately slow rate, especially at least as slowly as the rate of corrosion of the electrode portion.

One preferred material for at least part of the clip is therefore a conductive polymer. As for the pond,
Non-conductive polymers, carbonaceous materials and blue metals. Preferred polymers include crosslinked olefin-based polymers, such as polyethylene.

If desired, the clip can be dimensionally recoverable, e.g. heat-shrinkable, so that upon heating or heating, the groove 9 will fit tightly around the electrode part, thereby providing good electrical contact and electrolyte flow. Suppress intrusion. The dimensions of the clip shown in Figure 4 are such that the thickness of the material between the two grooves and between each groove and the base is preferably 0.5 to 10 mm, preferably 1 to 5 mm, and The length is 5 to 100m
n, more preferably 10 to 50 mm.

This clip is used to interconnect two similar or different electrode sections. For example, one electrode may include a carbonaceous anode section and the power electrode may include, for example, a titanium or platinum anode section. May include. One or both of the grooves may be used to hold a power supply wire or cable or to hold a connection between two wires or cables. This clip may be used as a means of applying power to the electrodes. For example, a power supply cable may have its ends stripped of insulation, or its outer surface may be rendered electrically conductive even though the cable ends are not stripped of insulation. Said end is then placed in correspondence with the clip by being placed in the groove 9 or in some other way. The conductive clip in the live state is then connected to a certain appropriate electrode section. The method of connecting a power supply cable for this purpose is to remove its insulation and connect the exposed conductor by means of a conductive (e.g. conductive polymer) plug or wrap (such as tape wrap). , tailored to the exact diameter to sit within the groove. The plug or wrap may be placed in place by heat-shrinkable positioning means such as a sleeve on the cable. More simply, the plug may be a heat-shrinkable conductive polymer.

FIG. 5 shows a clip 7 with means 10 for reducing the resistance between the two grooves; such means include a metal arrangement within the clip, as shown. The second metal has a lower resistivity and the conductive polymer provides a less corrosive coating.

This idea is discussed separately below. That is, by providing a clip (somewhat in the form of a piece rather than in the form of a block) and provided with a polymeric, drop-active coating in all areas except where the electrode elements come into contact, in said areas The coating may be lacking in coating or may include an electrically conductive polymer.

FIG. 6 shows the same structure except that the grooves 6 are arranged on opposite surfaces.
Lap 7 is shown as in FIG.

In Figure 57, the grooves 9 are provided on opposite surfaces and perpendicular to each other. Such a configuration is useful for mesh electrodes having orthogonal electrode elements in rows and columns, as shown in FIG.

The clip in Figure 8 consists of a base 11 and two blocks 1.
2, each block 12 is provided with a recess for an electrode part. This base 11 may be flexible.

In FIG. 9, the electrical and mechanical interconnection functions are divided between conductive members 13 and blocks 14. In FIG.

This block 14 deforms the member 13 around the electrode member and holds the electrode member in place.

In FIG. 10, conductive members 15 provide electrical interconnections and some mechanical interconnections. Blocks 16 simply serve to position conductive members 15 with respect to the electrode portions. If is a metal, then this metal is
Preferably, it is a deactivated metal such as titanium, tantalum or niobium.

FIG. 11 shows additional retaining means 17 which retain or serve to retain the electrode part within the recess 9. FIG. In this case, the four parts naturally do not need to have a square cross section (ie, have a neck) so that the electrodes do not deviate.

Figure 11 also shows means such as a vial extending from the base of the crimp, or a screw or bolt extending into the clip. By these means,
The clip is fixed to a ponded article, for example a concrete layer. Both of the illustrated clips are provided with such connection means.

In FIG. 12, only one groove 18 is provided for positioning two (or more) electrode members. Although a direct electrical connection between the two members is meaningless due to the small contact area, this configuration reduces the surface area between each electrode part and the clip compared to the structure described above. It is small, but provides sufficient electrical contact for some purposes.

FIG. 13 shows a clip 7 with seven lunges 19,
7. It is adapted to be held in a suitable position, for example against a concrete or other surface, by means of a 7-lunge. The 7-run 19 may have holes, as shown, through which bottles or bolts can be inserted to reach the concrete.

In other embodiments, the bin may be attached to the underside of the 7-run 19. The clip 7 in FIG.
A cover 20 may be provided to apply additional pressure on the electrode portion lying on the surface. This cover 20, however, need not be electrically conductive and may be at least partially secured by a fitting 21. If such a cover is provided with a groove 9, it need not have a square or constricted cross-section.

In FIG. 14, the clip 22 includes one hole that is closed in cross-section and one groove 9. In FIG. This clip is inserted by sliding along the electrode part 6 from the end of the electrode part 6, and is then clipped or grabbed onto the electrode part of the pond in a conventional manner. The clip can have both (or all) holes closed in cross-sectional shape, but it is necessary to construct the desired electrode or a somewhat difficult shape of the electrode. Where the configuration of FIG. 14 is used, a suitable number of clips 22 can be inserted along the electrode members, and the electrode members are arranged in a mesh or other shape and then positioned at the desired location. Clips 22 to be slid in are clipped near the electrode sections to stabilize the structure and electrically interconnect the components at various points.

A variation of the configuration of FIG. 14 is shown in FIG. 15, in which the clip 7 is an integral (or permanently connected) part 23 with the electrode part 6.

FIG. 16 shows a preferred structure of two lips 7,
As shown by the dots at the ends, it has a central portion 24 with low resistivity. In this clip, desired electrical properties are combined with desired mechanical properties. This allows, in one embodiment, for example, polymers loaded with conductive fillers (such as carbon black or carbon).
The conductive portion 24 comprising the conductive polymer is not electrically conductive.
Alternatively, a support portion 25 with low conductivity is provided.

The conductive portion 24 may include a corrosion-resistant metal, in particular a metal that forms a conductive oxide. Such metals are often referred to as valve metals and include titanium, balanoum, platinum, and others. Part 24 like this
The reason for using conductive polymers is that conductive polymers are stress sensitive and prone to damage under unfavorable conditions, i.e. cracking or loss of elasticity, especially under corrosive conditions. In the example, a conductive material bridges the electrode element (not shown) located in the groove 9, and a non-conductive material holds the electrode element and the conductive material in electrical contact. The non-conductive (or low conductivity) material preferably has a degree of elongation of 10% and more preferably 20% in operation. It is shown that it is at least partially fixed and held at a suitable location on the support part 25 by the mating fitting part 26. However, it may also be fixed by simple gluing or by extrusion or molding methods. Furthermore, the portions 24 may be smaller than shown and simply extend from one groove 9 to the other, or they may be larger and extend substantially all around one or both of the grooves 9. It may be extended. This portion 24 preferably has a resistivity of less than 5 ohms elfi, more preferably less than 3 ohms ell. The clip 7 is, for example, shown in FIG. 3B described above and @1 below.
It may be provided with a groove 27 or a pond fixing means for fixing to the curved clip 7A shown in FIG.

Figure 17 shows a clip 28 that can be used as a curved clip 7a as illustrated in Figure 3B. This clip 28 may of course be curved, or it may of course be simply straight, serving to keep the loop of the electrode from kinking, in which case the loop is supported in some other way. Ru. This clip 28 includes a member 29 to which connecting members 30 are attached (or integrally formed), each of which has a groove 9 therein or for holding an electrode element. have the means of This electrode element is fitted or alternatively slid into the groove.

The clip 28 also includes a 7-lung or pond attachment member 31 for securing to the substrate, thereby
Electrode elements are provided on the substrate.

The clip 7 of FIG. 16 (or clip shape, for example with a uniform configuration) may be used with other clips, such as the curved clip 28 of FIG. 17. This is done by fitting the groove 27 of the clip 7 and the portion 32 of the clip 28. The result is shown in Figure 3B, with loops 8a, 8b connected to paths 6a, 6b.

In some instances, particularly where a straight groove in the clip receives a curved electrode element, a conductive paste or liquid is filled around the electrode element within the groove to enhance the electrical connection. Good too. Generally, a pan or liquid is desirable when the electrode element is of a different configuration or size or shape than the groove of the clip, or when the electrode element is susceptible to deformation after insertion into the groove.

As a result, the electrical interconnection means of the clip may (when applied) include an electrically conductive liquid or base Y. Paste is used herein as a general term to refer to a highly viscous, deformable material that does not flow easily and therefore does not flow.

This paste (or liquid) preferably includes an electrically conductive material dispersed within a liquid medium. This conductive material is carbon black, especially acetylene black, graphite 7
It may also contain fibres, carbon fibres, or metal fibers or particles, especially sticky oxides (called valve metals) such as titanium, palladium or platinum. This liquid medium preferably repels unwanted liquids, such as water. Preferred liquid media include some hydrocarbon oils, although some hydrocarbon oils are suitable.
Contains silicone oil. Typical additions of conductive material are from 1 to 150% by weight, in particular from 2S to 35%, these values being particularly suitable especially when adding acetylene black to silicone oils. These two components should be mixed well so that the acetylene black is wetted with oil. This takes 5 to 10 minutes using some shears. Preferably the paste has a 7 ohm am or less, more preferably 3.5 ohm cI
It is particularly preferred to have a volume resistivity of 2.5 ohms.

[Advantageous Effects of the Invention 1] According to the present invention, by using a suitable clip, construction is easy and a stable anti-corrosion function can be achieved over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing one embodiment of the construction of the corrosion prevention system of the present invention, FIG. 2 is a plan view showing one embodiment of the electrode and clip of the present invention, and FIGS. 3A and 3B are mesh FIG. 4 is a plan view showing a modified example of the electrode, FIG. 4 is a perspective view showing an embodiment of the clip of the present invention, FIG. 5 is a sectional view showing a modified example of the clip of the present invention, and FIG. FIG. 7 is a perspective view showing a modification of the clip of the present invention; FIG. 8 is a side view showing a modification of the clip of the invention; FIGS. 9 to 12 13 is a side view showing a modified example of the clip of the present invention, and FIGS. 13 to 17 are perspective views showing modified examples of the clip of the present invention. DESCRIPTION OF SYMBOLS 1... Concrete, 2... Reinforcement rod, 3... Electrode, 5... Power source, 6... Electrode element, 7... Clip, 8 a, 8 b... Loop, 9...・Groove, 10・
...Resistance reducing means, 11... Pace, 12... Block, 13.15... Conductive member, 14.16... Block, 17... Holding means, 18... Groove, 19.・
・7 lange, 20...cover, 21...fitting part, 2
2... Clip, 23... Integral part, 24... Conductive part, 25... Support part, 26... Fitting part, 28...
Clip, 30...Connection member, 31...Mounting member. Patent Applicant Raychem Corporation Agent Patent Attorney Aohaku Ao 1 other person IG 2 Otsude = JA FIG 5 FIG 6 FIG (9 \ ω F/G-/2 F!ni /3 IG-14 Otsuishi-15

Claims (14)

[Claims] (1) A mesh electrode suitable for use as an anode in a corrosion protection system, [1] having a number of spaced connections arranged in a mesh configuration and interconnecting an elongated electrode or electrodes. one or more elongated electrodes having: [2] a plurality of clips, each clip comprising:
A mechanical and electrical connection is provided between the electrode sections at one point of the connection, and the electrical connection at each electrode section has an electrical contact area of at least more than 25 mm^2, and this connection is Corrosion protection system characterized in that it is elastically biased so that when the size of the attached electrode portion is reduced, such mechanical and electrical connections are maintained by the elastic recovery of the clip. (2) The corrosion prevention system according to claim 1, wherein the electrical contact area is at least 100 mm^2. (3) Claims 1 or 2 in which each clip includes a conductive polymeric part that makes electrical connection with the electrode part.
Corrosion protection systems as described in any of the paragraphs. (4) The corrosion prevention system according to any one of claims 1 to 3, wherein each electrode is a flexible electrode having a surface containing a conductive polymer. (5) the pressure applied by the clip on the electrode is at least 0.01 psi (0.0007 psi) in the area of electrical contact;
kg/cm^2) Claims 1 to 4
Corrosion protection systems as described in any of the paragraphs. (6) the pressure is at least 0.05 psi (0.003
6. The corrosion prevention system according to claim 5, wherein the corrosion resistance is 2 kg/cm^2). (7) The pressure applied by the clip on the electrode is at least 0.1 to 1 psi (0.0
07 to 0.07 kg/cm^2) Corrosion prevention system according to any one of claims 1 to 6. (8) The electrical connection resistance between the electrode parts at each connection part is
8. A corrosion protection system according to any one of claims 1 to 7, wherein the resistance is 25 ohms or less. (9) The corrosion prevention system according to claim 8, wherein the resistance is 10 ohms or less. (10) [1] Arranging one or more elongated electrodes in a desired mesh pattern, and [2] using elastically deformable clips around the mesh connections; A method for forming a mesh electrode according to any one of claims 1 to 9, which connects electrode parts. (11) A method for forming a mesh electrode according to claim 10, wherein the elongated electrodes are arranged on the surface of a concrete structure containing reinforcing bars. (12) A method for cathodically protecting a corrosive substrate, comprising establishing a potential difference between the substrate as a cathode and a mesh electrode according to any one of claims 1 to 9. (13) A method of applying a reinforced concrete structure to cathodic protection of reinforcing rods, in which a mesh electrode according to any one of claims 1 to 9 is fixed to the surface of the structure. Methods that include. (14) [1] having at least two indentations, each indentation being constructed of an electrically conductive material and capable of receiving an electrode portion and having electrical contact with the electrode portion over a surface area of at least 25 mm^2; [2] restricting movement between the recesses and, by resilient biasing, said exposed surface being able to contact said electrical interconnection means, said electrical interconnection means being interconnected; 10. A clip suitable for use in the manufacture of a mesh electrode according to any one of claims 1 to 9, comprising mechanical interconnection means for maintaining contact.