阅读说明：本技术 核电厂埋地管道阴极保护有效性监测系统 (Nuclear power plant buried pipeline cathodic protection effectiveness monitoring system ) 是由 章强 刘朝 魏松林 肖调兵 黄红科 方江 高路杨 但体纯 陈银强 陈黉君 侯涛 于 2020-05-09 设计创作，主要内容包括：本公开属于核电维修技术领域,具体涉及一种核电厂埋地管道阴极保护有效性监测系统。本公开实施例中,由于试片的通电电位和断电电位之差既可以包括测试过程中外加电流阴极保护系统产生的欧姆电压降,又可以包括牺牲阳极系统,以及其它杂散电流干扰产生的欧姆电压降,因此,本公开实施例通过试片的通电电位和断电电位之差,可以在待测管道无法与牺牲阳极断开的情况下,更加全面的确定测试过程中存在欧姆电压降,进而使确定的待测管道的阴极保护电位能够更加准确反应待测管道阴极保护实际状态。(The disclosure belongs to the technical field of nuclear power maintenance, and particularly relates to a system for monitoring cathode protection effectiveness of a buried pipeline of a nuclear power plant. In the embodiment of the present disclosure, the difference between the energization potential and the power-off potential of the test strip may include an ohmic voltage drop generated by an external current cathodic protection system in the testing process, and may include a sacrificial anode system, and an ohmic voltage drop generated by interference of other stray currents, so that the difference between the energization potential and the power-off potential of the test strip in the embodiment of the present disclosure may more comprehensively determine that there is an ohmic voltage drop in the testing process under the condition that the pipeline to be tested cannot be disconnected from the sacrificial anode, and further enable the determined cathodic protection potential of the pipeline to be tested to more accurately reflect the actual state of the cathodic protection of the pipeline to be tested.)

1. The utility model provides a nuclear power plant's buried pipeline cathodic protection validity monitoring system which characterized in that, nuclear power plant's buried pipeline cathodic protection validity monitoring system includes: cathodic protection test stake, potential measurement subsystem and controlling means, the potential measurement subsystem includes: the test strip comprises a first reference electrode, a second reference electrode, a first potential acquisition recorder, a second potential acquisition recorder, a switch and a test piece;

the device comprises a cathode protection test pile, a first reference electrode, a second reference electrode, a first potential acquisition recorder, a second potential acquisition recorder and a second potential acquisition recorder, wherein the cathode protection test pile is connected with a pipeline to be tested which is buried underground, the pipeline to be tested is connected with a cathode protection power supply and an auxiliary anode ground bed, the cathode protection test pile is also connected with the first reference electrode, the first reference electrode is inserted into the ground surface, and the first potential acquisition recorder is connected in series between the first reference electrode;

the test piece comprises a defect part, the material of the defect part is the same as that of the pipeline to be detected, the test piece is buried in soil above the pipeline to be detected, and the second reference electrode is inserted into the ground surface above the defect part;

the second reference electrode is connected with the cathodic protection test pile, and the second potential acquisition recorder and the switch are connected in series between the second reference electrode and the cathodic protection test pile;

the defect component is connected with one end of a cable, and the other end of the cable is connected between the second potential acquisition recorder and the switch;

the control device is respectively connected with the first potential acquisition recorder and the second potential acquisition recorder, the control device can acquire first potential data acquired by the first potential acquisition recorder, the control device can also acquire second potential data acquired by the second potential acquisition recorder under the condition that the switch is closed, and third potential data acquired by the second potential acquisition recorder under the condition that the switch is open;

the control device takes the difference between the second potential data and the third potential data as ohmic voltage drop;

and the control device determines the cathodic protection potential of the pipeline to be detected according to the first potential data and the determined ohmic voltage drop.

2. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 1, further comprising: a first flip-flop and a second flip-flop;

the first trigger is connected with the switch, and the second trigger is connected with the second potential acquisition recorder;

the moment when the first trigger triggers the switch to be switched off is the same as the moment when the second trigger triggers the second potential acquisition recorder to acquire data;

the moment when the first trigger triggers the switch to be closed is the same as the moment when the second trigger triggers the second potential acquisition recorder to acquire data.

3. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 1, wherein the area of said defective component exposed to the soil is the same as the largest defective area of said pipeline under test.

4. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 1, wherein the system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant comprises: a plurality of potential measurement subsystems;

the pipeline to be measured comprises a plurality of areas to be measured, and each electronic measurement subsystem is arranged on the earth surface corresponding to one area to be measured;

and the control device determines the cathodic protection potential of the region to be measured corresponding to each potential measurement subsystem according to the first potential data, the second potential data and the third potential data acquired from each potential measurement subsystem.

5. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 4, wherein each test block is buried directly above the axis of the pipeline to be tested.

6. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 1, wherein said test strip further comprises an anticorrosion component, and the material of said anticorrosion component is the same as the material of the anticorrosion layer of said pipeline to be tested.

7. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 5, wherein said coupon is in the shape of a cake.

8. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 7, wherein said defective component and said corrosion protection component are both in a cake shape, a groove is formed on the upper surface of said corrosion protection component, and said defective component is embedded in said groove.

9. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 6, wherein the material of said corrosion protection component comprises polyvinyl chloride.

10. The system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to claim 1, wherein the material of said defective component comprises steel.

Technical Field

The invention belongs to the technical field of nuclear power maintenance, and particularly relates to a system for monitoring the effectiveness of cathode protection of a buried pipeline in a nuclear power plant.

Background

The buried steel pipelines of the nuclear power plant are laid underground, and the soil corrosion of the buried steel pipelines is slowed down by adopting a protective measure combining an anticorrosive coating and regional cathodic protection. But with the increase of the service life of the buried pipeline, the quality of the anticorrosive coating is inevitably degraded; in addition, the anticorrosive coating inevitably generates anticorrosive coating defects during processing, installation and maintenance, and the cathodic protection system is used as a last important barrier to slow down soil corrosion of the pipeline body at the anticorrosive coating defects.

The evaluation of the cathodic protection potential at the defect of the anticorrosive coating of the buried pipeline is one of important evaluation parameters of the regional cathodic protection effectiveness of the buried pipeline, the accurate evaluation of the cathodic protection potential is related to the normal operation of a regional cathodic protection system of the buried pipeline of the nuclear power plant, and the evaluation of the effectiveness of the anticorrosive measures of the buried pipeline of the nuclear power plant is also related to, and the evaluation becomes one of the focuses of continuous aging management attention of the buried pipeline of the nuclear power plant. Generally speaking, in the process of measuring the cathodic protection potential of a buried pipeline, ohmic voltage drop generated by the buried pipeline and soil around the buried pipeline affects the cathodic protection potential of the buried pipeline, so that the accuracy of the potential measurement result of the buried pipeline is reduced. Therefore, how to effectively eliminate the ohmic voltage drop becomes an urgent problem to be solved.

Disclosure of Invention

In order to overcome the problems in the related art, a system for monitoring the effectiveness of cathode protection of a buried pipeline in a nuclear power plant is provided.

According to an aspect of the disclosed embodiment, a system for monitoring effectiveness of cathodic protection of a buried pipeline of a nuclear power plant is provided, which comprises: cathodic protection test stake, potential measurement subsystem and controller, the potential measurement subsystem includes: the test strip comprises a first reference electrode, a second reference electrode, a first potential acquisition recorder, a second potential acquisition recorder, a switch and a test piece;

the device comprises a cathode protection test pile, a first reference electrode, a second reference electrode, a first potential acquisition recorder, a second potential acquisition recorder and a second reference electrode, wherein the cathode protection test pile is connected with a pipeline to be tested which is buried underground, the pipeline to be tested is connected with a cathode protection power supply and an auxiliary anode ground bed, the cathode protection test pile is also connected with the first reference electrode, the first reference electrode is inserted into the ground surface, and the first potential acquisition recorder is connected in series between the first reference electrode and;

the test piece comprises a defect part, the material of the defect part is the same as that of the pipeline to be detected, the test piece is buried in soil above the pipeline to be detected, and the second reference electrode is inserted into the ground surface above the defect part;

the second reference electrode is connected with the cathodic protection test pile, and the second potential acquisition recorder and the switch are connected in series between the second reference electrode and the cathodic protection test pile;

the defect component is connected with one end of a cable, and the other end of the cable is connected between the second potential acquisition recorder and the switch;

the controller is respectively connected with the first potential acquisition recorder and the second potential acquisition recorder, the controller can acquire first potential data acquired by the first potential acquisition recorder, the controller can also acquire second potential data acquired by the second potential acquisition recorder under the condition that the switch is closed, and third potential data acquired by the second potential acquisition recorder under the condition that the switch is disconnected;

the controller takes a difference between the second potential data and the third potential data as an ohmic voltage drop;

and the controller determines the cathodic protection potential of the pipeline to be detected according to the first potential data and the determined ohmic voltage drop.

In one possible implementation manner, the system for monitoring the effectiveness of cathodic protection of the buried pipeline of the nuclear power plant further includes: a first flip-flop and a second flip-flop;

the first trigger is connected with the switch, and the second trigger is connected with the second potential acquisition recorder;

the moment when the first trigger triggers the switch to be switched off is the same as the moment when the second trigger triggers the second potential acquisition recorder to acquire data;

the moment when the first trigger triggers the switch to be closed is the same as the moment when the second trigger triggers the second potential acquisition recorder to acquire data.

In a possible implementation manner, the area of the defect component exposed in the soil is the same as the maximum defect area of the pipeline to be detected.

In one possible implementation, the system for monitoring the effectiveness of cathodic protection of buried pipelines of a nuclear power plant comprises: a plurality of potential measurement subsystems;

the pipeline to be measured comprises a plurality of areas to be measured, and each electronic measurement subsystem is arranged on the earth surface corresponding to one area to be measured;

and the controller determines the cathodic protection potential of the region to be measured corresponding to each potential measurement subsystem according to the first potential data, the second potential data and the third potential data acquired from each potential measurement subsystem.

In a possible implementation manner, each test block is buried right above the axis of the pipeline to be measured.

In a possible implementation manner, the test piece further comprises an anticorrosion component, and the anticorrosion component is made of the same material as that of the pipeline to be tested.

In one possible implementation, the test strip is cake-shaped.

In a possible implementation manner, the defective component and the corrosion-resistant component are both cake-shaped, a groove is formed in the upper surface of the corrosion-resistant component, and the defective component is embedded in the groove.

In one possible implementation, the material of the corrosion protection component comprises polyvinyl chloride.

In one possible implementation, the material of the defective component includes steel.

The invention has the beneficial effects that: in the embodiment of the present disclosure, the difference between the power-on potential and the power-off potential of the test strip may include an ohmic voltage drop generated by the impressed current cathodic protection system during the test process, and may also include the sacrificial anode system, and an ohmic voltage drop generated by interference of other stray currents.

Drawings

FIG. 1 is a schematic diagram illustrating a nuclear power plant buried pipeline cathodic protection effectiveness monitoring system according to an exemplary embodiment.

Fig. 2 is a top view of a test strip in a system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant, according to an exemplary embodiment.

Fig. 3 is a cross-sectional view of a coupon in a system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to an exemplary embodiment.

Detailed Description

The invention is described in further detail below with reference to the figures and the embodiments.

FIG. 1 is a schematic diagram illustrating a nuclear power plant buried pipeline cathodic protection effectiveness monitoring system according to an exemplary embodiment. As shown in fig. 1, the system for monitoring the effectiveness of cathodic protection of buried pipelines in nuclear power plants may include: a cathodic protection test pile 10, a potential measurement subsystem, which may include: a first reference electrode 12, a second reference electrode 20, a first electric potential collecting recorder 11, a second electric potential collecting recorder 21, a switch 22 and a test piece 23.

In the embodiment of the present disclosure, the controller may be, for example, a computer device such as a notebook computer, a desktop computer, or a server, and the type of the controller is not limited in the embodiment of the present disclosure.

As an example of this embodiment, a to-be-measured pipe 32 buried underground may be connected to a cathodic protection power source 31 and an auxiliary anode ground bed 30, a lower end of a cathodic protection test pile 10 may be inserted into soil to be measured and connected to the pipe 32, an upper end of the cathodic protection test pile 10 may be exposed from the ground surface, a lower end of a first reference electrode 12 may be inserted into the ground surface, an upper end of the cathodic protection test pile 10 may be connected to an upper end of the first reference electrode 12 through a cable, and a first potential collecting recorder 11 may be connected in series between the first reference electrode 12 and the cathodic protection test pile 10.

The test strip 23 may include a defective component (not shown), and the material of the defective component may be the same as the material of the pipe 32 to be tested (for example, the body of the pipe 32 to be tested may be alloy steel, and the material of the defective component may also be alloy steel with the same composition), so that the test strip 23 can simulate the potential of the defective portion of the pipe 32 to be tested more accurately. The test piece 23 can be embedded in the soil above the pipeline 32 to be tested (for example, the embedded depth of the test piece 23 can be consistent with the embedded depth of the pipeline, and for example, the test piece can be embedded in the soil at a position 10 to 20 cm away from the ground surface, so that the cost of manpower and material resources is saved), and the lower end of the second reference electrode 20 can be inserted into the ground surface above the defective component.

The upper end of the second reference electrode 20 can be connected with the cathodic protection test pile 10, and a second potential acquisition recorder 21 and a switch 22 can be connected in series between the second reference electrode 20 and the cathodic protection test pile 10; the defect part can be connected with one end of a cable, and the other end of the cable can be connected between the second potential acquisition recorder 21 and the switch 22;

the cathodic protection power source 31 can be controlled to output a constant current, and the switch 22 can be closed to keep the test strip 23 energized for a preset time (for example, 24 hours or longer), so that the test strip 23 is sufficiently polarized. The controller can obtain the first potential data of the pipe 32 to be measured in the power-on state, which is collected by the first potential collecting recorder 11. The controller may acquire the second potential data of the test piece 23 acquired by the second potential acquisition recorder 21 in the power-on condition when the switch 22 is closed, and may acquire the third potential data of the test piece 23 acquired by the second potential acquisition recorder 21 in the power-off condition when the switch 22 is open.

The controller takes the difference between the second potential data and the third potential data as ohmic voltage drop; the controller may determine a cathodic protection potential of the pipe 32 under test based on the first potential data and the determined ohmic voltage drop. For example, the controller may use the difference between the first potential data and the ohmic voltage drop as the cathodic protection potential of the pipe 32 under test. For another example, the controller may determine a product of the ohmic voltage drop and the adjustment factor, and use a difference between the first potential data and the product as the cathodic protection potential of the pipe 32 under test.

Generally speaking, a regional cathodic protection system for a buried pipeline in a nuclear power plant generally adopts the combined protection of impressed current and a sacrificial anode, and the sacrificial anode is directly connected to the outer wall of the pipeline through a copper core cable, and only through the instant power-off of a cathodic protection power supply, only the ohmic voltage drop generated by the cathodic protection power supply system can be eliminated, but not the ohmic voltage drop generated by the sacrificial anode system, in the embodiment of the disclosure, because the difference between the electrifying potential and the power-off potential of a test piece can include the ohmic voltage drop generated by the impressed current cathodic protection system in the test process, can also include the ohmic voltage drop generated by the sacrificial anode system and other stray current interferences, therefore, the ohmic voltage drop in the test process can be more comprehensively determined through the difference between the electrifying potential and the power-off potential of the test piece, and the connection between the pipeline to be tested and the sacrificial anode and the cathodic protection power supply does not need to be, the normal operation of the impressed current cathodic protection system and the sacrificial anode cathodic protection system is ensured, and the cathodic protection potential of the pipeline to be tested can be more accurately obtained.

In one possible implementation, the system for monitoring the effectiveness of cathodic protection of a buried pipeline in a nuclear power plant may further include: a first flip-flop and a second flip-flop; the first trigger can be connected with the switch, and the second trigger can be connected with the second potential acquisition recorder;

the moment when the first trigger triggers the switch to be switched off is the same as the moment when the second trigger triggers the second potential acquisition recorder to acquire data; the closing time of the trigger switch of the first trigger is the same as the time of the trigger switch of the second trigger for the second potential acquisition recorder to acquire data. For example, the timers of the first trigger and the second trigger may be synchronized (for example, the first trigger and the second trigger may implement the timer synchronization through a GPS signal, and the first trigger and the second trigger may implement the timer synchronization through other communication methods, which is not limited in the embodiments of the present disclosure), so that the first trigger and the second trigger may send trigger signals at the same time, and when the trigger switch of the first trigger is turned off, the second trigger may also trigger the second potential collection recorder to collect data at the same time; when the first trigger switch is switched off, the second trigger can also trigger the second potential acquisition recorder to acquire data at the same time. Therefore, the automatic and accurate collection of the power-on potential data and the power-off potential data of the test piece can be realized without a complex control system.

In one possible implementation, the area of the defective component exposed to the soil is the same as the largest defective area of the pipe to be tested. Therefore, the determined cathodic protection potential can reflect the potential condition of the maximum defect part of the pipeline to be detected, and if the determined cathodic protection potential meets the protection requirement, the cathodic protection of the defect parts of other anticorrosive coatings of the pipeline to be detected can be determined to be sufficient, so that the cathodic protection effectiveness is further ensured.

In one possible implementation, the system for monitoring the effectiveness of cathodic protection of a buried pipeline in a nuclear power plant may further include: a plurality of potential measurement subsystems; wherein, each component in each potential measurement subsystem can be arranged according to the mode.

The pipeline to be measured can be divided into a plurality of areas to be measured, and each electronic measurement subsystem is arranged on the earth surface corresponding to one area to be measured;

and the controller determines the cathodic protection potential of the region to be measured corresponding to each potential measurement subsystem according to the first potential data, the second potential data and the third potential data acquired from each potential measurement subsystem. Therefore, the cathodic protection potentials of a plurality of different areas of the pipeline to be tested can be respectively determined, so that the distribution state of the cathodic protection potentials along the pipeline to be tested is obtained, and the cathodic protection condition of the pipeline to be tested is more comprehensively and truly reflected.

In a possible implementation manner, each test block may be buried right above the axis of the pipe to be measured.

In a possible implementation manner, the test piece may further include a corrosion prevention component, and the material of the corrosion prevention component is the same as the material of the corrosion prevention layer of the pipe to be measured. Therefore, the test piece can simulate the actual state of the defect part of the pipeline to be tested more vividly.

Fig. 2 is a top view of a test strip in a system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant, according to an exemplary embodiment. Fig. 3 is a cross-sectional view of a coupon in a system for monitoring the effectiveness of cathodic protection of a buried pipeline of a nuclear power plant according to an exemplary embodiment. As shown in fig. 2 and 3, the test piece may be in a cake shape, the defective part 40 and the corrosion prevention part 41 may be in a cake shape, a groove is formed on the upper surface of the corrosion prevention part 41, and the defective part 40 is embedded in the groove. Wherein, the material of the corrosion prevention part can comprise polyvinyl chloride. The material of the defective component may include steel.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.