CN107988603B - Device and method for protecting cable from corrosion by using externally applied current of rainwater conduction - Google Patents

Abstract

The invention discloses an impressed current protection cable corrosion protection device utilizing rainwater conduction, which comprises a cable and an auxiliary anode arranged on an insulating sheath at the outer side of the cable; the end part of the cable is provided with a cathode access point and an impressed current protection device; the impressed current protection device comprises a reference electrode, a direct current power supply and a potentiostat, wherein the reference electrode is arranged on an insulating sheath at the outer side of the cable and is insulated from the cable; one end of the direct current power supply is connected with the auxiliary anode through a potentiostat, and the other end of the direct current power supply is connected to the cathode access point through the potentiostat. The invention can strengthen the inhibition of corrosion of the bridge cable in rainfall weather, lighten the influence of corrosion on the service life of the bridge cable, greatly improve the service life of the current cable, and simultaneously, the system is in an open circuit state when no rainfall exists, and no current passes through to save electric energy.

Description

Anti-corrosion device and method for using rainwater to conduct external current protection cable

technical field

The invention mainly relates to the field of construction and maintenance of long-span bridges, in particular to an anti-corrosion device and method for an applied current protection cable using rainwater conduction.

Background technique

With the rapid development of society, long-span bridges are playing an increasingly important role as an important part of modern transportation. Suspension bridges, cable-stayed bridges and hanger arch bridges account for a considerable proportion of long-span bridges, and are the main types of bridges spanning large rivers and straits, and sometimes even the only reasonable bridge type. Bridge cables are the main load-bearing components of suspension bridges or cable-stayed bridges, and their reliability and durability are directly related to the overall structural safety of the bridge. For example, the design service life of existing bridge slings is 20 years, but the actual service life of slings is rarely more than 20 years; it is far from the design service life of bridges of 100 years. The root causes of bridge cable damage are mainly stress corrosion and corrosion fatigue. From the point of view of the failure mechanism of bridge cables, it is mainly caused by the joint action of atmospheric rainwater corrosion and external loads, that is, the damage caused by the coupling action of stress corrosion and corrosion fatigue, which becomes the weak link of the entire cable, and will affect the load bearing capacity of the bridge in severe cases. force. Since corrosion is accidental, the loss of cable bearing capacity caused by the coupling effect of stress corrosion and corrosion fatigue is difficult to determine through analytical methods, thus resulting in inaccurate prediction of the service life of bridge cables. The cracked and damaged parts of the cable sheath are often the most severely corroded. Once the sheath fails, the cable steel wire will be corroded to varying degrees, and even lead to broken wires and broken cables, which directly affect the structural safety of the bridge. . In rainy weather, due to the joint action of rainwater and oxygen in the atmosphere, this phenomenon is more serious and causes greater economic losses.

Contents of the invention

In order to solve the above problems, the present invention provides an applied current protection cable anti-corrosion method using rainwater to conduct electricity, which can enhance the inhibition of bridge cable corrosion in rainy weather, reduce the impact of corrosion on the service life of bridge cables, and can greatly improve the current cable performance. At the same time, the system is in an open circuit state when there is no rainfall, and no current passes through to save electric energy.

The technical solution adopted in the present invention is: an applied current protection cable anti-corrosion device that uses rainwater to conduct electricity, including a cable and an auxiliary anode installed on the outer insulating sheath of the cable; the end of the cable is provided with a cathode connection point and applied current protection device; the applied current protection device includes a reference electrode, a DC power supply and a potentiostat, and the reference electrode is installed on the insulating sheath outside the cable and insulated from the cable; the DC One end of the power supply is connected to the auxiliary anode through a potentiostat, and the other end is connected to the cathode access point through a potentiostat.

Further, the cathode access point is set at the end of the cable opposite to the auxiliary anode.

Further, the auxiliary anode is made of mixed oxide, ferrosilicon or lead material.

Further, the reference electrode is made of a mercurous sulfate electrode or a calomel electrode.

The invention also discloses a corrosion-resistant method for protecting cables by using rainwater to conduct electricity with an applied current. The method includes the following steps:

The first step is to select some points on the cable according to the cracking and damage condition of the cable sheath, and set the auxiliary anode on the point, and the auxiliary anode is insulated from the cable;

The second step is to set the cathode access point at a suitable position on the cable;

The third step is to select one or several points at the damaged position of the cable sheath, and set a reference electrode at the point;

The fourth step is to select a suitable position at the bottom of the cable to set up the potentiostat;

The fifth step is to connect the potentiostat with auxiliary anode, cathode access point and reference electrode with wires;

In the sixth step, when there is rainfall, the rainfall rainwater is used as an electrolyte solution to connect the auxiliary anode and the cable to form a conductive circuit, which causes the cable to generate cathodic polarization and inhibits the cable from rusting.

The beneficial effects produced by the present invention are: the present invention utilizes rainfall and rainwater to form a conductive circuit, and the conductive circuit produces cathodic polarization on the cable at the damaged part of the cable, which enhances the inhibition of bridge cable corrosion, and at the same time, no current passes through when there is no rain, Saving electric energy and reducing the impact of corrosion on the service life of the cable can greatly increase the service life of the current cable.

Description of drawings

Fig. 1 is the structure schematic diagram of the applied current protection device for the anti-corrosion of cable of the embodiment of the present invention;

Fig. 2 is a schematic cross-sectional view of a cable structure of an embodiment of the present invention;

Fig. 3 is a schematic diagram of a longitudinal section of a cable structure of an embodiment of the present invention;

Fig. 4 is a connection structure diagram of an applied current protection device for anti-corrosion cables according to an embodiment of the present invention.

In the figure: 1. Cable, 2. Insulation sheath, 3. Auxiliary anode, 4. Cathode access point, 5. DC power supply, 6. Damaged part of sheath, 7. Reference electrode, 8. Potentiostat, 9 , Voltmeter, 10, Rainwater.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The invention discloses an applied current protection cable anti-corrosion device utilizing rainwater conduction, comprising a cable 1 and an insulating sheath 2 covering the outside of the cable 1, as shown in FIG. 2 . A plurality of auxiliary anodes 3 are evenly distributed on the insulating sheath 2, and a cathode access point 4 is set on the cable 1. The auxiliary anode 3 is based on the cracking and damage of the cable insulating sheath 2, the size of the cable, and the corrosion of the cable. The actual conditions such as the condition and the model of the auxiliary anode are arranged. The reference electrode 7 is arranged on the outside of the insulating sheath 2 of the cable and is in contact with it to ensure that it is insulated from the cable 1 when there is no rain.

As shown in Figure 1, the DC power supply 5 in the present invention is used to provide continuous, stable voltage or current, and one end of the DC power supply 5 is respectively connected with the plurality of auxiliary anodes 3 through a potentiostat 8, and its opposite end It is connected to the cathode access point 4 through a potentiostat 8 . The positive pole of the potentiostat 8 is connected to the auxiliary anode 3 , and the negative pole of the potentiostat 8 is connected to the cathode access point 4 . A voltmeter 9 is connected to the cable 1, and the voltmeter 9 can monitor the potential of the cable at the reference electrode in real time in rainy weather, compare the monitored potential index with the potential value of the protection standard, and control the output voltage of the potentiostat to make the cable is protected. The output current and output voltage of the potentiostat 8 can be calculated and determined according to the conditions of use, the current required by the protected cable structure and the resistance of the protection system loop.

As shown in Figure 3, the auxiliary anode 3 is arranged on the outside of the insulating sheath 2, and under the action of the external DC power supply 5, it provides electrons for the auxiliary anode 3, and at the same time conducts electricity through the rainfall 10, and connects with the cathode connection point of the cable 1 4 to form a conductive loop, so that the cathodic connection point 4 on the cable 1 is cathodically polarized, thereby inhibiting corrosion. The auxiliary anode 3 can be made of platinum sheet, platinized titanium, cast iron, graphite or lead-silver alloy. The auxiliary anode 3 has the characteristics of electrochemical inertness, low anode polarizability, and less loss.

When it rains, since the DC power supply 5 can apply a certain DC current to the part of the cable 1 exposed to the atmosphere and the auxiliary anode 3 through the potentiostat 8, an electrochemical reaction will occur on the surface of the auxiliary anode 3, so that it can continuously flow to the cable 1. The cathodic access point 4 of the cable 1 supplies electrons, thereby causing cathodic polarization of the cable 1 . When the potential of the cathode connection point 4 of the cable 1 is negative to a certain point value, the anodic dissolution process of corrosion will be inhibited, and then the corrosion of the bridge cable will be inhibited, which can greatly improve the service life of the current cable and eliminate the rainfall. The impact of corrosion on the service life of the cable in weather, when there is no rainfall, the system is in an open circuit state, and there is no current in the circuit to save electric energy, and the economic and social benefits are remarkable.

When the present invention is implemented, multiple cables 1 can be simultaneously protected, and the potentiostat in FIG. 1 can be connected in parallel with multiple cables 1 to apply external current protection to them.

In the description of this specification, descriptions referring to the terms "one embodiment", "a part of embodiments", "example" and the like mean that specific features, structures, materials, quantities or characteristics described in conjunction with the embodiment or example are included in this specification. In at least one embodiment or example of the invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials, quantities or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (5)

1. An applied current protection cable anti-corrosion device utilizing rainwater conduction is characterized in that: it comprises a cable and an auxiliary anode installed on the cable outer insulating sheath; the end of the cable is provided with a cathode access point and Applied current protection device; the described applied current protection device comprises a reference electrode, a DC power supply and a potentiostat, and the described reference electrode is installed on the insulating sheath outside the cable and insulated from the cable; the DC power supply One end is connected to the auxiliary anode through a potentiostat, and the other end is connected to the cathode access point through a potentiostat. 2. The anti-corrosion device for applied current protection cables using rainwater conduction according to claim 1, wherein the cathode access point is arranged at the end of the cable opposite to the auxiliary anode. 3. The anti-corrosion device for applied current protection cables utilizing rainwater conduction according to claim 1, wherein said auxiliary anode is made of mixed oxide, ferrosilicon or lead material. 4. The anticorrosion device for applied current protection cables utilizing rainwater conduction according to claim 1, wherein the reference electrode is made of a mercury sulfate electrode or a calomel electrode. 5. An applied current protection cable anti-corrosion method utilizing rainwater conduction, is characterized in that: comprises the following steps: The first step is to select some points on the cable according to the cracking and damage condition of the cable sheath, and set the auxiliary anode on the point, and the auxiliary anode is insulated from the cable; The second step is to set the cathode access point at a suitable position on the cable; The third step is to select one or several points at the damaged position of the cable sheath, and set a reference electrode at the point; The fourth step is to select a suitable position at the bottom of the cable to set up the potentiostat; The fifth step is to connect the potentiostat with auxiliary anode, cathode access point and reference electrode with wires; In the sixth step, when there is rainfall, the rainfall rainwater is used as an electrolyte solution to connect the auxiliary anode and the cable to form a conductive circuit, which causes the cable to generate cathodic polarization and inhibits the cable from rusting.

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