阅读说明：本技术 一种基于双参比电极的极低电位等势线绘制系统与方法 (System and method for drawing extremely-low potential equipotential lines based on double-reference electrode ) 是由 章强 黄红科 刘朝 魏松林 娄骁 肖调兵 陈银强 桂春 于 2020-12-30 设计创作，主要内容包括：本发明涉及核电厂埋地管道维修技术领域,具体公开了一种基于双参比电极的极低电位等势线绘制系统与方法,该系统包括第一便携式硫酸铜参比电极、测距仪、电位采集记录仪和第二便携式硫酸铜参比电极,其中,所述第一便携式硫酸铜参比电极依次与测距仪、电位采集记录仪和第二便携式硫酸铜参比电极相连接,所述电位采集记录仪用来测量第一便携式硫酸铜参比电极和第二便携式硫酸铜参比电极之间的电位差,所述测距仪用来测量第一便携式硫酸铜参比电极和第二便携式硫酸铜参比电极之间的距离。该系统的使用,实现了在埋地管道非开挖的情况下,对埋地管道防腐层缺陷的极低电位等势线进行绘制,操作快捷方便,结构设计巧妙,功能可靠,操作便捷。(The invention relates to the technical field of maintenance of buried pipelines of nuclear power plants, and particularly discloses a system and a method for drawing an extremely-low potential equipotential line based on double-reference electrode. The use of the system realizes drawing of extremely low potential equipotential lines of the buried pipeline anticorrosive coating defect under the non-excavation condition of the buried pipeline, and has the advantages of rapid and convenient operation, ingenious structural design, reliable function and convenient operation.)

1. The utility model provides a system is drawn to extremely low potential equipotential line based on two reference electrodes which characterized in that: the system comprises a first portable copper sulfate reference electrode (4), a distance meter (5), a potential acquisition recorder (6) and a second portable copper sulfate reference electrode (7), wherein the first portable copper sulfate reference electrode (4) is sequentially connected with the distance meter (5), the potential acquisition recorder (6) and the second portable copper sulfate reference electrode (7), the potential acquisition recorder (6) is used for measuring the potential difference between the first portable copper sulfate reference electrode (4) and the second portable copper sulfate reference electrode (7), and the distance meter (5) is used for measuring the distance between the first portable copper sulfate reference electrode (4) and the second portable copper sulfate reference electrode (7).

2. The system for drawing the extremely low potential equipotential lines based on the dual-reference electrode is characterized in that: the portable copper sulfate reference electrode is characterized in that the pipeline anticorrosive coating defect (3) of the buried pipeline (1) is arranged below the portable copper sulfate reference electrode (4), and the portable copper sulfate reference electrode (4) is vertically and fixedly arranged on the surface layer above the pipeline anticorrosive coating defect (3) of the buried pipeline (1).

3. The system for drawing the extremely low potential equipotential lines based on the dual-reference electrode is characterized in that: the buried pipeline (1) is sequentially connected with a cathodic protection direct current power supply 8, a synchronous current breaker (9) and an auxiliary anode ground bed (10).

4. The system for drawing the extremely low potential equipotential lines based on the dual-reference electrode is characterized in that: and carrying out GPS synchronous setting on the synchronous current breaker (9), the potential acquisition recorder (6) and the distance meter (5).

5. The system for drawing the extremely low potential equipotential lines based on the dual-reference electrode is characterized in that: the second portable copper sulfate reference electrode (7) takes the first portable copper sulfate reference electrode (4) as a circle center, and measures the potential gradient between the first portable copper sulfate reference electrode (4) and the second portable copper sulfate reference electrode (7).

6. The system for drawing the extremely low potential equipotential lines based on the dual-reference electrode is characterized in that: the current output by the cathode protection direct current power supply (8) is constant current, and the magnitude of the current can be adjusted.

7. The system for drawing the extremely low potential equipotential lines based on the dual-reference electrode is characterized in that: the buried pipeline (1) is connected with a pipeline testing pile (2).

8. A method for drawing an extremely low potential equipotential line based on a double-reference electrode is characterized by comprising the following steps: vertically and fixedly inserting a first reference electrode into the ground surface above a point to be measured; vertically inserting a second reference electrode into any earth surface position around the first reference electrode to obtain the distance and the potential difference between the first reference electrode and the second reference electrode; and rotating the second reference electrode by taking the first reference electrode as a circle center, measuring potential differences and distances between a plurality of point positions around the first reference electrode and the first reference electrode, connecting the point positions with the same potential differences together, and drawing an equipotential line graph.

9. The method for drawing the extremely low potential equipotential line based on the dual-reference electrode, as recited in claim 8, wherein: the potential difference between the first reference electrode and the second reference electrode can be adjusted by increasing or decreasing the distance between the second reference electrode and the first reference electrode.

10. The method for drawing the extremely low potential equipotential line based on the dual-reference electrode, as recited in claim 8, wherein: the second reference electrode makes a circular motion around the first reference electrode at equal angles.

Technical Field

The invention belongs to the technical field of maintenance of buried pipelines in nuclear power plants, and particularly relates to a system and a method for drawing an extremely-low potential equipotential line based on a double-reference electrode.

Background

The buried steel pipeline of the nuclear power plant is buried underground, and the outer wall of the pipeline is coated with an anticorrosive coating to slow down the soil corrosion of the pipeline. With the increase of the service life of the buried pipeline, the corrosion-resistant layer inevitably degrades; in addition, during the construction or maintenance of the buried pipeline, mechanical damage or poor quality control of the backfill material (the backfill material contains stones) can inevitably exist, so that the anticorrosive coating is damaged, and the defect of the anticorrosive coating is generated. The defective part of the anticorrosive coating is preferentially affected by various erosion ions (chloride ions, sulfate ions and sulfur ions) in soil, and forms a large cathode-small anode corrosion battery with the complete part of the anticorrosive coating, so that the corrosion rate of the pipe body at the defective part of the anticorrosive coating is accelerated, and the corrosion degree is increased until the buried pipeline is corroded and perforated.

At present, technologies such as direct current potential gradient Detection (DCVG), alternating current potential gradient detection (ACVG) and PEARSON are generally adopted to locate the defects of the anticorrosive layer of the buried pipeline of the nuclear power plant, but the detection methods have poor stray current interference resistance, cannot realize quantitative detection on the size of the defects of the anticorrosive layer of the buried pipeline, cannot well guide the excavation and repair priority level of the anticorrosive layer of the buried pipeline, and bring difficulty and risk to aging management of the buried pipeline of the nuclear power plant.

Disclosure of Invention

The invention aims to provide a system and a method for drawing an extremely-low potential equipotential line based on a double-reference electrode, which are used for drawing the extremely-low potential equipotential line of a buried pipeline anticorrosive coating defect under the condition of non-excavation of the buried pipeline, so that the quantitative evaluation of the shape and size of the buried pipeline anticorrosive coating defect is realized, the shape and size of the buried pipeline anticorrosive coating defect of a nuclear power plant are mastered timely and accurately, and a technical support is provided for the evaluation and repair of the buried pipeline anticorrosive coating of the nuclear power plant.

The technical scheme of the invention is as follows:

the system comprises a first portable copper sulfate reference electrode, a distance meter, a potential acquisition recorder and a second portable copper sulfate reference electrode, wherein the first portable copper sulfate reference electrode is sequentially connected with the distance meter, the potential acquisition recorder and the second portable copper sulfate reference electrode, the potential acquisition recorder is used for measuring the potential difference between the first portable copper sulfate reference electrode and the second portable copper sulfate reference electrode, and the distance meter is used for measuring the distance between the first portable copper sulfate reference electrode and the second portable copper sulfate reference electrode.

The portable copper sulfate reference electrode is vertically and fixedly arranged on the surface layer above the pipeline anticorrosive coating defect of the buried pipeline.

The buried pipeline is sequentially connected with a cathode protection direct current power supply, a synchronous current breaker and an auxiliary anode ground bed.

And carrying out GPS synchronous setting on the synchronous current breaker, the potential acquisition recorder and the range finder.

And the second portable copper sulfate reference electrode takes the first portable copper sulfate reference electrode as a circle center, and measures the potential gradient between the first portable copper sulfate reference electrode and the second portable copper sulfate reference electrode.

The current output by the cathode protection direct current power supply is constant current, and the current can be adjusted.

The buried pipeline is connected with a pipeline testing pile.

A very low potential equipotential line drawing method based on double reference electrodes, said method comprises inserting the first reference electrode vertically and fixedly into the earth's surface above the point to be measured; vertically inserting a second reference electrode into any earth surface position around the first reference electrode to obtain the distance and the potential difference between the first reference electrode and the second reference electrode; and rotating the second reference electrode by taking the first reference electrode as a circle center, measuring potential differences and distances between a plurality of point positions around the first reference electrode and the first reference electrode, connecting the point positions with the same potential differences together, and drawing an equipotential line graph.

The potential difference between the first reference electrode and the second reference electrode can be adjusted by increasing or decreasing the distance between the second reference electrode and the first reference electrode.

The second reference electrode makes a circular motion around the first reference electrode at equal angles.

The invention has the following remarkable effects: according to the system and the method for drawing the extremely-low potential equipotential lines based on the double-reference electrode, the defects of the existing buried pipeline anticorrosive coating detection technology (DCVG, ACVG, PEARSON and the like) are overcome through the double-reference electrode, the extremely-low potential equipotential lines with the defects of the buried pipeline anticorrosive coating are drawn under the condition that the buried pipeline is not excavated, the operation is fast and convenient, the structure is ingenious, the function is reliable, and the operation is convenient.

Drawings

FIG. 1 is a schematic diagram of a system for drawing an extremely low potential equipotential line based on a dual reference electrode;

FIG. 2 is a schematic diagram of an elevational cross-section of a system for drawing an extremely low potential equipotential line based on a dual reference electrode;

FIG. 3 is a schematic drawing of a very low potential single-turn equipotential line based on dual reference electrodes;

FIG. 4 is a schematic drawing of an extremely low potential double-coil equipotential line based on a dual reference electrode;

in the figure: 1. burying a pipeline; 2. testing the pile through the pipeline; 3. defects of the pipeline anticorrosive coating; 4. a first portable copper sulfate reference electrode; 5. a range finder; 6. a potential acquisition recorder; 7. a second portable copper sulfate reference electrode; 8. a cathodic protection direct current power supply; 9. a synchronous current breaker; 10. an auxiliary anode ground bed.

Detailed Description

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

As shown in fig. 1-2, a system for drawing an extremely-low potential equipotential line based on a dual-reference electrode comprises a first portable copper sulfate reference electrode 4, a distance meter 5, a potential acquisition recorder 6 and a second portable copper sulfate reference electrode 7, wherein the first portable copper sulfate reference electrode 4 is sequentially connected with the distance meter 5, the potential acquisition recorder 6 and the second portable copper sulfate reference electrode 7, a pipeline corrosion protection layer defect 3 of a buried pipeline 1 is arranged below the first portable copper sulfate reference electrode 4, the first portable copper sulfate reference electrode 4 is vertically and fixedly arranged on a surface layer above the pipeline corrosion protection layer defect 3, and the second portable copper sulfate reference electrode 7 is vertically arranged on the surface layer; the buried pipeline 1 is sequentially connected with a cathodic protection direct current power supply 8, a synchronous current breaker 9 and an auxiliary anode ground bed 10, wherein the cathodic protection direct current power supply 8 outputs constant current and forms a loop with the auxiliary anode ground bed 10, and the buried pipeline 1 is also connected with a pipeline testing pile 2 to monitor the potential of the buried pipeline 1; the synchronous current breaker 9, the potential acquisition recorder 6 and the distance meter 5 are synchronously set by a GPS, the potential acquisition recorder 6 records the earth surface-ground potential gradient between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 by controlling the on-off of the synchronous current breaker 9, and the distance meter 5 records the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7; moving the second portable copper sulfate reference electrode 7, increasing or decreasing the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7, recording the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 when the potential difference between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 is 10mV, and marking the position of the second portable copper sulfate reference electrode 7; as shown in FIG. 3, the second portable copper sulfate reference electrode 7 was rotated clockwise 360 degrees around the first portable copper sulfate reference electrode 4, the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 was increased or decreased for each 30 degrees of rotation, the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 was recorded and the position of the second portable copper sulfate reference electrode 7 was marked when the potential difference between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 was 10mV, and an equipotential line with a potential difference of 10mV was drawn using the position information for the second portable copper sulfate reference electrode 7. As shown in FIG. 4, the second portable copper sulfate reference electrode 7 was rotated 360 degrees clockwise about the first portable copper sulfate reference electrode 4, the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 was increased or decreased for each 30 degrees of rotation, the distance between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 was recorded and the position of the second portable copper sulfate reference electrode 7 was marked when the potential difference between the first portable copper sulfate reference electrode 4 and the second portable copper sulfate reference electrode 7 was 10mV or 20mV, respectively, and equipotential lines having a potential difference of 10mV and 20mV were drawn using the position information for the second portable copper sulfate reference electrode 7.

A method for drawing an extremely-low potential equipotential line based on a double-reference electrode comprises the following steps:

(1) setting the cathodic protection direct current power supply 8 to a constant current output mode;

(2) carry out GPS synchronous set with current breaker 9 with current collection record appearance 6, distancer 5, the on/off mode is: electrifying for 4 seconds and powering off for 1 second;

(3) vertically and fixedly inserting a first portable copper sulfate reference electrode 4 on the earth surface above a pipeline anticorrosive coating defect 3 of a buried pipeline 1;

(4) determining the value of an equipotential line, vertically inserting a second portable copper sulfate reference electrode 7 into the ground surface around the first portable copper sulfate reference electrode 4, increasing or decreasing the distance between the second portable copper sulfate reference electrode 7 and the first portable copper sulfate reference electrode 4 along the direction of the connection line of the second portable copper sulfate reference electrode 7 and the first portable copper sulfate reference electrode 4 until the indication value of a potential acquisition recorder 6 reaches the determined equipotential line value, and recording the indication value of a distance meter 5 and the position of the second portable copper sulfate reference electrode 7 at the moment;

(5) rotating the second portable copper sulfate reference electrode 7 by a certain angle by taking the fixed point of the first portable copper sulfate reference electrode 4 as a circle center, and repeating the operation in the step (4) until the second portable copper sulfate reference electrode 7 rotates around the first portable copper sulfate reference electrode 4 for a circle;

(6) the equipotential lines are plotted by the recorded distance between the second portable copper sulfate reference electrode 7 and the first portable copper sulfate reference electrode 4, and the position of the second portable copper sulfate reference electrode 7.