Corrosion detection device for buried pipelines

Abstract

The application provides a buried pipeline corrosion detection device, which comprises an underground detection device and a control cabinet. The underground detection device comprises a soil fixation sleeve, a counterweight pipe installed in the soil fixation sleeve, and a test steel pipe fixed in the counterweight pipe as a test cathode. The test steel pipe, a T-shaped reference electrode and a T-shaped auxiliary anode electrode are in contact with soil under the action of the counterweight pipe. The control cabinet comprises a control cabinet body, a heating device arranged on the control cabinet body and used for heating liquid, a temperature controller connected with the heating device and used for controlling parameters of the heating device, and a current controller connected with the test steel pipe, the T-shaped reference electrode, a T-shaped auxiliary anode cable and a negative electrode cable and used for controlling the potential of the T-shaped auxiliary anode cable and receiving potential information of the test steel pipe and the negative electrode cable.

Description

Technical Field

[0001] This invention relates to the field of metal corrosion monitoring, and more specifically, to a device for detecting corrosion in buried pipelines. Background Technology

[0002] In existing technologies, buried metal pipeline corrosion monitoring devices and methods collect the maximum instantaneous current density by using an induced charge device buried in the soil above the pipeline to analyze the corrosion status of the buried steel pipe. Alternatively, by using a multi-metal sheath device, the characteristics of the hanging plate accurately reflecting metal corrosion are maintained, while the corrosion time of each layer can be determined. This method is mainly used for corrosion detection inside pipelines. Or, by distributing acoustic wave sensors on the pipeline surface, the local quality changes on the pipeline surface are sensed to achieve corrosion monitoring.

[0003] However, it cannot determine the corrosion state; nor can it achieve the corrosion degree assessment by collecting and comparing the protection potential of the production pipeline and using a specific device, as described in this patent. It also cannot determine the corrosion state based on the current protection status and the pipeline's environment. It is mainly used for internal corrosion detection, or when the current protection status cannot be determined in conjunction with the pipeline's environment.

[0004] Therefore, the main research direction is to provide a device that can detect and evaluate the degree of corrosion and analyze and judge the corrosion status in combination with the environment in which the pipeline is located. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] Therefore, the first objective of this invention is to provide a device for detecting corrosion of buried pipelines.

[0007] To achieve the above objectives, the first aspect of the present invention provides a buried pipeline corrosion detection device for production pipelines under cathodic protection. The detection device includes: an underground detection unit and a control cabinet; the underground detection unit includes: a soil-stabilizing sleeve; a counterweight pipe installed inside the soil-stabilizing sleeve; a test steel pipe fixed inside the counterweight pipe as a test cathode; a first supply pipe and a first return pipe connected to both ends of the test steel pipe; a pipe surface temperature sensor installed on the surface of the test steel pipe for detecting the surface temperature; a T-shaped reference electrode fixed on the counterweight pipe; a T-shaped auxiliary anode electrode fixed on the counterweight pipe; under the action of the counterweight pipe, the test steel pipe, the T-shaped reference electrode, and the T-shaped auxiliary anode electrode are in contact with the soil; and a negative electrode cable. The control cabinet is connected to the production pipeline and includes: a control cabinet body; a heating device mounted on the control cabinet body for heating liquid; a second liquid supply pipe, one end of which is connected to the first liquid supply pipe and the other end of which is connected to the heating device for supplying liquid to the first liquid supply pipe; a second liquid return pipe, one end of which is connected to the first liquid return pipe and the other end of which is connected to the heating device for recovering liquid flowing out of the first liquid return pipe; a temperature controller connected to the heating device for controlling the parameters of the heating device; and a current controller connected to the test steel pipe, the T-type reference electrode, the T-type auxiliary anode cable, and the negative electrode cable for controlling the potential of the T-type auxiliary anode cable and receiving potential information from the test steel pipe and the negative electrode cable.

[0008] Furthermore, the heating device includes: an electric heating outer tube, mounted on the control cabinet; an electric heating rod, fixed inside the electric heating outer tube, used to heat the liquid; a first temperature transmitter, connected to the electric heating outer tube, used to detect the temperature of the liquid flowing out of the electric heating outer tube; and a circulation pump, one end of which is connected to the electric heating outer tube, and the other end of which is connected to a second return pipe, used to provide power for the circulation of the liquid.

[0009] Furthermore, the heating device also includes: a first temperature transmitter housing, with a first temperature regulator disposed inside the first temperature regulator housing; one end of the first temperature transmitter housing is connected to an electric heating outer tube, and the other end of the first temperature transmitter housing is connected to a circulating pump; a safety relief valve, disposed on the first temperature transmitter housing, for ensuring that the pressure inside the first temperature transmitter housing is in the installation state; and a pressure relief drain pipe, connected to the safety relief valve, for discharging liquid or gas discharged from the safety relief valve.

[0010] Furthermore, the buried pipeline corrosion detection device also includes: a T-shaped auxiliary anode nut for fixing the T-shaped auxiliary anode to the configuration pipe; a T-shaped reference electrode nut for fixing the T-shaped reference electrode to the configuration pipe; a T-shaped auxiliary anode cable, one end of which is connected to the T-shaped auxiliary anode and the other end of which is connected to the current controller; and a T-shaped reference electrode cable, one end of which is connected to the T-shaped reference electrode and the other end of which is connected to the current controller.

[0011] Furthermore, the buried pipeline corrosion detection device also includes a second temperature transmitter, which is installed on the production pipeline and connected to the temperature controller to send the temperature of the production pipeline to the temperature controller.

[0012] Furthermore, the buried pipeline corrosion detection device also includes: a third temperature transmitter, which is installed on the test steel pipe. One end of the third temperature transmitter is connected to the pipe surface temperature sensor, and the other end of the third temperature transmitter is connected to the temperature controller. The third temperature transmitter is used to send the temperature of the test steel pipe to the temperature controller.

[0013] Furthermore, the buried pipeline corrosion detection device also includes: a first relay, one end of which is connected to a temperature controller and the other end of which is connected to an electric heating rod, the first relay being used to control the operation of the electric heating rod; and a second relay, one end of which is connected to a temperature controller and the other end of which is connected to a circulating pump, the second relay being used to control the operation of the circulating pump.

[0014] Furthermore, the buried pipeline corrosion detection device also includes: a controllable rectifier, which is installed inside the control cabinet. One end of the controllable rectifier is connected to a T-shaped auxiliary anode cable, and the other end of the controllable rectifier is connected to a negative cable, thereby forming a closed loop. The controllable rectifier is connected to a second controller, which controls the voltage output by the controllable rectifier.

[0015] Furthermore, the buried pipeline corrosion detection device also includes: a first voltmeter, connected to the positive terminal of the controllable rectifier, used to detect the output voltage of the controllable rectifier; an ammeter, connected to the positive terminal of the controllable rectifier, used to detect the output current of the controllable rectifier; and a second voltmeter, one end of which is connected to a T-type reference cable, and the other end of which is connected to the test steel pipe, used to detect the voltage across the test steel pipe.

[0016] Furthermore, the buried pipeline corrosion detection device also includes: a casing head, which is set at one end of the soil stabilization casing for fixing the soil stabilization casing; and a ground support, which is set on the control cabinet for supporting the control cabinet.

[0017] The buried pipeline radiation detection device of this invention can simulate the temperature operating conditions of a production pipeline, realize on-site measurement of key corrosion parameters, and determine the pipeline corrosion status by comparing the on-site protection potential of the production pipeline. Furthermore, after being interlocked with the power supply of the cathodic protection system of the production pipeline, it can achieve real-time control and adjustment of the cathodic protection output status, ensuring that the cathodic protection effect is at its optimal state. This buried pipeline radiation detection device can accurately monitor the corrosion status of pipelines under cathodic protection conditions. In particular, it proposes a buried pipeline corrosion monitoring device that can be applied in the field, combining the analysis of the pipeline's environment to determine the corrosion status, comparing the current protection status, and interacting with the power supply equipment to adjust protection indicators, thereby improving the corrosion protection effect.

[0018] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention. Attached Figure Description

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0020] Figure 1 This is a schematic diagram of the structure of an underground detection device according to an embodiment of the present invention;

[0021] Figure 2 This is one of the structural schematic diagrams of a control cabinet according to an embodiment of the present invention;

[0022] Figure 3 This is one of the structural schematic diagrams of a control cabinet according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of a buried pipeline corrosion detection device according to an embodiment of the present invention;

[0024] Figure 5 This is a coordinate schematic diagram of a buried pipeline corrosion detection device according to an embodiment of the present invention.

[0025] in, Figures 1 to 4 The correspondence between the figure labels and nouns in the figures is as follows:

[0026] 1. Soil stabilization sleeve, 2. Sleeve head, 3. Counterweight pipe, 4. T-shaped auxiliary anode, 5. T-shaped auxiliary anode cable, 6. T-shaped auxiliary anode nut, 7. T-shaped reference electrode, 8. T-shaped reference electrode cable, 9. T-shaped reference electrode nut, 10. Test steel pipe, 11. First supply pipe, 12. First return pipe, 13. Pipe surface temperature sensor, 14. Temperature sensor cable, 15. Negative electrode cable, 16. Test steel pipe potential acquisition cable, 17. Control cabinet, 18. Floor support, 19. Conduit, 20. Second supply pipe, 21. Second return pipe, 22. Temperature controller, 23. First 24 Temperature transmitter, 25 Second temperature transmitter, 26 Third temperature transmitter, 27 First relay, 28 Second relay, 29 Electric heating rod, 30 Circulating pump, 31 Housing of first temperature transmitter, 32 Safety relief valve, 33 Pressure relief drain pipe, 34 Electric heating outer tube, 35 Current controller, 36 Controllable rectifier, 37 First voltmeter, 48 Ammeter, 49 Second voltmeter, 40 Potential acquisition cable for testing steel pipe, 41 Power switch, 42 Incoming cable, 46 Residual current device, 47 Production pipeline, 49 Cable connecting production pipeline. Detailed Implementation

[0027] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0028] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0029] The following reference Figures 1 to 4 This invention describes a buried pipeline corrosion detection device in some embodiments.

[0030] like Figures 1 to 4 As shown, an embodiment of the first aspect of the present invention provides a buried pipeline corrosion monitoring device, comprising a detection device buried underground and a control cabinet installed on the ground. See [link to relevant documentation]. Figure 1 The underground testing device includes a soil stabilization sleeve 1, a sleeve head 2; a counterweight pipe 3 installed inside the soil stabilization sleeve, a T-shaped auxiliary anode 4 and a T-shaped auxiliary anode cable 5 connected to the counterweight pipe 3 from bottom to top, a T-shaped auxiliary anode nut 6, a T-shaped reference electrode 7, a T-shaped reference electrode cable 8, a T-shaped reference electrode nut 9, a test steel pipe 10, a first return water pipe 12 connected to the test steel pipe, a pipe surface temperature sensor 13 probe installed on the surface of the test steel pipe, a temperature sensor cable 14, a negative electrode cable 15 connected to the surface of the test pipe, and a test steel pipe potential acquisition cable 16.

[0031] The ground-mounted control cabinet includes a control cabinet body 17, a floor support 18, a conduit 19, and a second liquid supply pipe 20 and a second liquid return pipe 21 connected to the underground detection device, see [link to details]. Figure 2 The control cabinet internal devices are shown in the attached diagram. Figure 3 The system includes a temperature controller 22, a second temperature transmitter 24 connected to the temperature controller 22, a temperature sensor probe connected to the monitored production pipeline 47, and a cable 49 connected to the production pipeline; a third temperature transmitter 25 and an underground device pipe surface temperature sensor 13 probe and a temperature sensor cable 14 connected to it; a first relay 26 and a second relay 27 connected to the temperature controller 22; an electric heating rod 28 connected to the first relay 26, and a circulating pump 29 connected to the second relay 27; a first temperature transmitter housing 30, a safety relief valve 31 installed on the upper side of the first temperature transmitter housing 30, and a pressure relief drain pipe 32 connected to the outlet of the safety relief valve 31; a first temperature transmitter 23 installed at the center of the first temperature transmitter housing 30, and an electric heating rod 28 installed at the center of the electric heating outer tube 33; the electric heating outer tube 33, the first temperature transmitter housing 30, and the circulating pump 29 are connected by PPR pipes. The system includes a current controller 34, a controllable rectifier 35 connected to the current controller 34, a first voltmeter 36 and an ammeter 37 connected to the outlet of the controllable rectifier 35, a controllable rectifier output T-shaped auxiliary anode cable 5, a controllable rectifier output negative cable 15, a second voltmeter 40 connected to the current controller 34, a potential acquisition cable 41 for the test steel pipe of the underground device connected to the second voltmeter 40, a T-shaped reference electrode cable 8, a controllable rectifier 35 output T-shaped auxiliary anode cable 5 connected to the underground buried device, and a cable 49 connected to the production pipeline connected to the current controller 34. A power switch 44, an incoming cable 45 connected to the power switch, and a residual current device 46 connected to the power switch via a cable; a temperature controller 22, a current controller 34, a controllable rectifier 35, a first voltmeter 36, an ammeter 37, a second voltmeter 40, a first relay 26, a second relay 27, an electric heating rod 28, a circulating pump 29, a first temperature transmitter 23, a second temperature transmitter 24, and a third temperature transmitter 25 are connected to the residual current device 46 via cables. A first water supply pipe 11 is connected to the circulating pump 29, and a first return water pipe 12 is connected to the electric heating outer pipe 33. A negative cable 15 on the surface of the test pipe is connected to the negative output cable 15 of the controllable rectifier; a T-shaped auxiliary anode cable 5 is connected to the T-shaped auxiliary anode output cable 5 of the controllable rectifier.

[0032] (1) According to Figure 1 Assemble the underground portion of the invention device (the material of the test fittings used is the same as that of the monitored production pipeline 47); the specific installation sequence is as follows: First, the installation of the soil stabilization sleeve 1: Select the installation point of the underground device, the recommended installation point is located in, for example, Figure 4 A hole is drilled at a vertical distance of 50cm from one side of the production pipeline 47, using a soil drilling drill with the same outer diameter as the soil stabilizing sleeve 1. The hole is 10cm to 20cm deeper than the pipeline burial depth. The soil stabilizing sleeve 1 is then installed into the drilled hole, with its bottom depth equal to the pipeline burial depth. Figure 4 The bottom burial depth of the production pipeline 47 is consistent, and the soil-stabilizing sleeve 1 is left 30cm to 50cm above the ground. Second, the connection and installation of the internal components of the soil-stabilizing sleeve 1: the two ends of the test steel pipe 10 are connected to heat-fused insulated elbows, and the insulated elbows are connected to the first water supply pipe 11 and the first water return pipe 12; after cleaning the surface of the test steel pipe 10, a 13-patch type temperature sensor probe is installed on the pipe surface near the insulated elbow; the surface of the test steel pipe 10 is protected with adhesive tape; the openings of the first water supply pipe 11 and the first water return pipe 12 are kept facing upwards, and an opening of 1cm is made on the lower surface of the test steel pipe 10. 2 Up to 100cm 2 (Calculate the break area based on the pipe corrosion protection level obtained from the test); Install the first water supply pipe 11 and the first water return pipe 12 of the connected test steel pipe 10 into the pre-opened position of the counterweight pipe 3 from bottom to top, and pass the temperature sensor cable through the opening of the counterweight pipe 3 where the nearest insulated elbow is located; Install the T-shaped reference electrode 7 into the pre-opened position of the counterweight pipe 3 from bottom to top, and tighten the T-shaped reference electrode nut 9 of the T-shaped reference electrode 7; Install the T-shaped auxiliary anode 4 and the T-shaped auxiliary anode cable 5 into the pre-opened position of the counterweight pipe 3 from bottom to top, and tighten the T-shaped auxiliary anode cable nut 9. The T-shaped auxiliary anode nut 6 of the auxiliary anode 4; the T-shaped auxiliary anode cable 5, the temperature sensor cable 14, the negative electrode cable 15 connected to the surface of the test pipe, and the test steel pipe potential acquisition cable 16 are bound to the first water supply pipe 11 from bottom to top with nylon cable ties; the components inside the soil-stabilizing sleeve 1 that have been installed and connected are placed into the soil-stabilizing sleeve 1 that has been buried in the soil from top to bottom; the key components inside the soil-stabilizing sleeve 1, the downward-facing opening of the test steel pipe 10, the downward-facing part of the T-shaped auxiliary anode 4, and the T-shaped reference electrode 7, are in close contact with the soil under the weight of the counterweight pipe 3. Finally, the sleeve head 2 is installed at the upper end of the soil-stabilizing sleeve 1, and the first water supply pipe 11 and the first return water pipe 12 pass through the reserved holes on the sleeve head 2; the T-shaped auxiliary anode cable 5, the temperature sensor cable 14, the negative electrode cable 15 connected to the surface of the test pipe, and the test steel pipe potential acquisition cable 16 pass through the reserved cable holes on the sleeve head 2.

[0033] (2) According to Figure 2The ground portion of the invention device is arranged as follows: the ground support 18 is installed above the installation position of the underground device soil stabilization sleeve 1; the control cabinet 17 is installed on the ground support 18; the cable from the underground device passes through the conduit 19, the cable pre-drilled hole on the conduit head 2, and the pre-drilled hole on the bottom surface of the ground control cabinet 17; the first water supply pipe 11 inside the control cabinet 17 is connected to the upper end of the second liquid supply pipe 20 passing through the pre-drilled opening below the control cabinet 17, and the lower end of the second liquid supply pipe 20 is connected to the first water supply pipe 11 from the underground device; the first return water pipe 12 inside the control cabinet 17 is connected to the upper end of the second return water pipe 21 passing through the pre-drilled opening below the control cabinet 17, and the lower end of the 21-water supply pipe is connected to the first return water pipe 12 from the underground device.

[0034] (3) According to Figure 3 Install and inspect the connections of the various devices inside the cabinet.

[0035] (4) Remove the safety relief valve 31 on the upper part of the housing 30 of the first temperature transmitter in the control cabinet 17. Insulating oil (transformer oil can be used) is intermittently and slowly injected into the housing 30 of the first temperature transmitter through the installation port of the safety relief valve 31. After filling, 20 ml is drawn out with a syringe and the safety relief valve 31 is reinstalled.

[0036] (5) Start the control cabinet power supply 44. The temperature controller 22 collects the temperature of the monitored production pipeline 47 surface through the second temperature transmitter 24 and the second temperature transmitter 24 buried on the surface of the production pipeline 47; the temperature controller 22 collects the temperature of the test steel pipe 10 surface through the third temperature transmitter 25 and the 13-temperature sensor probe installed on the surface of the underground test steel pipe of the present invention. The temperature controller 22 collects the temperature of the medium in the process through the first temperature transmitter 23.

[0037] (6) When the surface temperature of the test steel pipe is 3°C lower than the surface temperature of the production pipeline 47 (this temperature difference can be set), the temperature controller 22 connects the power supply of the electric heating rod 28 through the first relay 26 to heat the insulating oil in the process connected to the underground device; at the same time, the temperature controller 22 connects the power supply of the circulation pump 29 through the second relay 27, and under the action of the circulation pump 29, the medium flows through the inside of the buried test steel pipe 10 to realize the heating of the buried test steel pipe 10.

[0038] (7) When the temperature controller 22 detects that the surface temperature of the test steel pipe is equal to the surface temperature of the production pipeline 47, the controller 1 cuts off the power supply to the electric heating rod 28 through the first relay 26 to stop heating. Steps 5-7 achieve the goal of the underground test steel pipe 10 and the production pipeline 47 being the same.

[0039] (8) Simultaneously with step 5, the power switch 44 is activated, and the current controller 34 connects the cable 49 connected to the production pipeline and the negative cable 15 on the underground test steel pipe 10 through the internal circuit to achieve cathodic protection of the test steel pipe 10 for at least 15 minutes (this time 34 can be set by the controller 2); the current controller 34 collects the cathodic protection energizing potential VTBH1 of the currently monitored production pipeline 47 through the cable 49 connected to the production pipeline (set to a separate storage location).

[0040] (9) The current controller 34 disconnects the cable 49 connected to the production pipeline and the negative cable 15 on the test steel pipe 10, and at the same time, the current controller 34 controls the controllable rectifier 35 to start working.

[0041] (10) Under the control of the current controller 34, the controllable rectifier 35 starts from 0V output and increases the output voltage by a certain voltage amplitude (such as 0.2V). At the same time, the first voltmeter 36 and the ammeter 37 measure the output voltage VT0.2, VT0.4, VT0.6, etc. and the output current IT0.2, IT0.4, IT0.6, etc. of the controllable rectifier and feed the values ​​back to the current controller 34 for storage in a fixed position. The stable output time of each voltage amplitude is 200 seconds, disconnected for 20 seconds and then increased to the next voltage.

[0042] (11) At the same time as each voltage value stabilizes, the current controller 34 transmits the operating status information of the controllable rectifier 35 to the second voltmeter 40. The second voltmeter 40 automatically adjusts the data acquisition cycle to 30 seconds and reads a set of energized protection potential data of the test steel pipe when each set of voltages is output stably:

[0043] VT0230, VT0260, VT0290, VT02120, VT02150, VT02180;

[0044] VT0430, VT0460, VT0490, VT04120, VT04150, VT04180;

[0045] VT0630, VT0660, VT0690, VT06120, VT06150, VT06180.

[0046] The second voltmeter 40 transmits each set of power-on protection potential data to the current controller 34 for fixed-position storage, and reads the potential at 150 seconds after each power-on voltage as the power-on protection potential corresponding to each output voltage, such as VT02150, VT04150, VT06150, etc., and stores it in a fixed position.

[0047] (12) At the end of each voltage amplitude value, while the current controller 34 controls the controllable rectifier 35 to disconnect the output, it transmits the disconnection status information of the controllable rectifier 35 to the second voltmeter 40. The second voltmeter 40 automatically adjusts the data acquisition period to 50 milliseconds. While the current controller 34 controls the controllable rectifier 35 to disconnect the output, the second voltmeter 40 reads a set of instantaneous power failure protection potentials at 50 millisecond intervals.

[0048] VD0250, VD02100, VD02150, VD02200, VD02250, VD02300;

[0049] VD0450, VD04100, VD04150, VD04200, VD04250, VD04300;

[0050] VD0650, VD06100, VD062150, VD06200, VD06250, VD06300.

[0051] Voltmeter 2 transmits the power-off protection potential data of each group to the current controller 34 for storage in a fixed location, and reads the potential at the moment of disconnection of each output voltage 150 milliseconds as the power-off protection potential corresponding to each output voltage, such as VD02150, VD04150, VD06150, etc., and stores it in a fixed location.

[0052] (13) The current controller 34 automatically calculates the rate of change of the potential difference between the on-off protection and the rate of increase of the potential data of the off-off protection. The calculation formula is as follows:

[0053] The rate of change of potential difference between on and off power supply is VTDCBHVn = (VTn150 - VDn150) / VDn150;

[0054] The rate of increase in power-off potential is VDZJVn=(VDn+1150-VDn150) / VDn150.

[0055] (14) For ease of understanding, please refer to Figure 5 The current controller 34 calculates from the minimum data, and when the rate of change of the on / off potential difference VTDCBHVn ≥ 5%, the corresponding... Figure 5 The data at inflection point #1 represents the first cathodic protection potential, which is the most positive protection potential under the current production conditions. Current controller 34 records the corresponding on-state protection potential VTbh1 and off-state protection potential VTbh1. When the off-state potential increase rate VDZJVn ≤ 5%, the corresponding... Figure 5 The data at the inflection point #2 is the second cathode protection potential, which is the most negative protection potential under the current production conditions. The current controller 34 records the corresponding power-on protection potential VTbh2 and power-off protection potential VTbh2.

[0056] (15) Current controller 34 shuts down the output of the controllable rectifier.

[0057] (16) The current controller 34 reconnects the production pipeline cable 49 and the negative cable 15 on the test steel pipe 10 buried underground through the internal circuit to monitor the cathodic protection potential.

[0058] (17) Corrosion status judgment: The current controller 34 compares and monitors the cathodic protection potentials VTBH1 and VTbh1, VTbh2; when VTBH1 < VTbh1, it is determined that the current detected pipeline (current detection position) is under-protected and the pipeline is corroded; when VTbh1 < VTBH1 ≤ VTbh2, it is determined that the current detected pipeline (current detection position) is in good protection and the pipeline is not corroded; when VTBH1 > VTbh2, it is determined that the current detected pipeline (current detection position) is in over-protection and the pipeline is at high risk of hydrogen evolution corrosion.

[0059] (18) The current controller 34 can communicate with the potentiostat communicator of the protection station to adjust the output status of the potentiostat, thereby keeping the output of the cathodic protection system in a good state.

[0060] In this specification, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0061] In the description of this specification, the terms "one embodiment," "some embodiments," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0062] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A device for detecting corrosion of a buried pipeline, characterized by, The utility model relates to a kind of underground detection device and control cabinet;The underground detection device includes: Soil stabilizing casing pipe; Counterweight pipe, installed in the soil stabilizing casing pipe; Test steel pipe, fixed in the counterweight pipe, as test cathode; The test steel pipe two ends are respectively connected with first liquid supply pipe and first liquid return pipe; Pipe surface temperature sensor, set on the test steel pipe surface, for detecting the temperature of the test steel pipe surface; T-shaped reference electrode, fixed on the counterweight pipe; T-shaped auxiliary anode electrode, fixed on the counterweight pipe; Under the action of the counterweight pipe, the test steel pipe, the T-shaped reference electrode and the T-shaped auxiliary anode electrode contact with soil; Negative electrode cable, connected with production pipeline; The control cabinet includes: Control cabinet cabinet body; Heating device, set on the control cabinet cabinet body, for heating liquid; Second liquid supply pipe, one end of the second liquid supply pipe communicates with the first liquid supply pipe, the other end of the second liquid supply pipe communicates with the heating device, for supplying liquid to the first liquid supply pipe; Second liquid return pipe, one end of the second liquid return pipe communicates with the first liquid return pipe, the other end of the second liquid return pipe communicates with the heating device, for recovering liquid flowing out of the first liquid return pipe; Temperature controller, connected with the heating device, for controlling the parameters of the heating device; Current controller, connected with the test steel pipe, the T-shaped reference electrode, the T-shaped auxiliary anode cable and the negative electrode cable, for controlling the potential of the T-shaped auxiliary anode cable, and receiving the potential information of the test steel pipe and the negative electrode cable. The heating device includes: Electric heating outer pipe, set on the control cabinet cabinet body; 2. The apparatus of claim 1, wherein Electric heating rod, fixed in the electric heating outer pipe, for heating liquid; First temperature transmitter, communicating with the electric heating outer pipe, for detecting the temperature of liquid flowing out of the electric heating outer pipe; Circulating pump, one end of the circulating pump communicates with the electric heating outer pipe, the other end of the circulating pump communicates with the second liquid return pipe, for providing power for the circulation of the liquid. The heating device further includes: First temperature transmitter housing, the first temperature transmitter is set in the first temperature transmitter housing;One end of the first temperature transmitter housing communicates with the electric heating outer pipe, the other end of the first temperature transmitter housing communicates with the circulating pump; 3. The apparatus of claim 2, wherein, Safety pressure relief valve, set on the first temperature transmitter housing, for ensuring that the pressure in the first temperature transmitter housing is in the installed state; Pressure relief and liquid discharge pipe, communicating with the safety pressure relief valve, for discharging liquid or gas discharged by the safety pressure relief valve. Further include: T-shaped auxiliary anode nut, for fixing the T-shaped auxiliary anode on the counterweight pipe; 4. The apparatus of claim 1, wherein T-shaped reference electrode nut, for fixing the T-shaped reference electrode on the counterweight pipe; T-shaped auxiliary anode cable, one end of the T-shaped auxiliary anode cable is connected with the T-shaped auxiliary anode, the other end of the T-shaped auxiliary anode cable is connected with the current controller. ​ ​ A T-shaped reference electrode cable, one end of the T-shaped reference electrode cable is connected with the T-shaped reference electrode, the other end of the T-shaped reference electrode cable is connected with the current controller.

5. The apparatus of claim 1 wherein, Further comprising: A second temperature transmitter, arranged on the production pipeline, in communication with the temperature controller, for sending the temperature of the production pipeline to the temperature controller.

6. The apparatus of any one of claims 1 to 5, wherein, Further comprising A third temperature transmitter, arranged on the test steel pipe, one end of the third temperature transmitter is connected with the pipe surface temperature sensor, the other end of the third temperature transmitter is connected with the temperature controller, and the third temperature transmitter is used to send the temperature of the test steel pipe to the temperature controller.

7. The apparatus of claim 2 wherein, Further comprising: A first relay, one end of the first relay is connected with the temperature controller, the other end of the first relay is connected with the electric heating rod, and the first relay is used to control the work of the electric heating rod; A second relay, one end of the second relay is connected with the temperature controller, the other end of the second relay is connected with the circulating pump, and the second relay is used to control the work of the circulating pump.

8. The apparatus of any one of claims 1 to 5, wherein, Further comprising: A controllable rectifier, arranged in the control cabinet body, one end of the controllable rectifier is connected with the T-shaped auxiliary anode cable, the other end of the controllable rectifier is connected with the negative electrode cable, thereby forming a closed loop, the controllable rectifier is connected with a second controller, and the second controller controls the voltage output by the controllable rectifier.

9. The apparatus of claim 8, wherein, Further comprising: A first voltmeter, connected with the positive electrode of the controllable rectifier, for detecting the output voltage of the controllable rectifier; An ammeter, connected with the positive electrode of the controllable rectifier, for detecting the output current of the controllable rectifier; A second voltmeter, one end of the second voltmeter is connected with the T-shaped reference cable, the other end of the second voltmeter is connected with the test steel pipe, for detecting the voltage at both ends of the test steel pipe.

10. The apparatus of any one of claims 1 to 5, wherein, Further comprising: A casing head, arranged at one end of the soil fixation casing, for fixing the soil fixation casing; A floor support, arranged on the control cabinet body, for supporting the control cabinet body.

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