An automatic testing system for corrosion rate of natural gas pipelines

Abstract

The invention relates to an automatic testing system for corrosion rate of a natural gas pipeline, comprising a corrosion rate metering module, a data monitoring module, a data acquisition module, a control module, a data processing module, a real-time positioning and communication module and a power module; the power module adopts a rechargeable battery to provide power for the corrosion rate measuring module, the data monitoring module, the data acquisition module, the control module, the data processing module, the real-time positioning and communication module, wherein the corrosion rate metering module and the data monitoring module are located in one electric circuit, and the data acquisition module, the control module, the data processing module, the real-time positioning and communication module are located in another electric circuit; the invention can realize long-term or short-term automatic testing of the corrosion amount of a corrosion probe, automatically calculate the corrosion rate, and transmit the test result back to an intelligent cathode protection system in real time, thereby ensuring the accuracy of the corrosion rate measurement time and reducing the labor of personnel.

Description

Technical Field

[0001] The invention belongs to the technical field of pipeline cathodic protection, and in particular relates to an automatic testing system for the corrosion rate of a natural gas pipeline. Background Art

[0002] Most buried oil and gas pipelines are made of steel. During operation, they are inevitably affected by stray currents in the soil and corroded, perforated, or even ruptured, which seriously threatens the safe operation of oil and gas pipelines. At present, the commonly used anti-corrosion measures include adding corrosion inhibitors, applying internal and external anti-corrosion coatings, and cathodic protection measures. In order to determine the cathodic protection parameters, it is first necessary to determine the corrosion capacity of stray currents, bacteria, etc. in the soil near the pipeline. Usually, a test piece of the same material as the pipeline is buried at the depth of the pipeline. Readings are regularly taken from the corrosion rate tester set at the cathodic protection pile to obtain the corrosion capacity of the soil near the pipeline. At present, when measuring metal corrosion rates, handheld corrosion rate detectors are usually used for measurement, which has high labor costs and is easily affected by the surrounding environment or operators, resulting in data deviations.

[0003] In view of the above technical problems, improvements need to be made. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of difficulty in recording corrosion rate and to provide a natural gas pipeline corrosion rate automatic testing system which can detect and record corrosion rate and transmit it to an intelligent cathodic protection system.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is: a natural gas pipeline corrosion rate automatic testing system, including a corrosion rate metering module, a data monitoring module, a data acquisition module, a control module, a data processing module, a real-time positioning and communication module and a power module; the power module adopts a rechargeable battery to provide power for the corrosion rate measurement module, the data monitoring module, the data acquisition module, the control module, the data processing module, the real-time positioning and communication module, wherein the corrosion rate metering module and the data monitoring module are located in one electrical circuit, and the data acquisition module, the control module, the data processing module, the real-time positioning and communication module are located in another electrical circuit.

[0006] As a preferred solution of the present invention, the corrosion rate metering module is composed of a corrosion probe and a temperature compensation element, which are connected in series in the same circuit; the burial depth of the corrosion probe is the same as that of the pipeline.

[0007] As a preferred solution of the present invention, the corrosion probe resistance value calculation formula is: Temperature compensation unit resistance value calculation formula: Corrosion rate calculation formula: Among them, R Cis the resistance of the corrosion probe in ohms; U C is the voltage across the corrosion probe (21), in volts; I is the current flowing through the corrosion probe and the temperature compensation element, in amperes; R R is the resistance of the temperature compensation element in ohms; U R is the voltage across the temperature compensation element, in volts; a is the corrosion rate, in mm / (time), the time unit is consistent with the unit of t on the right side of the equation; t is the time for measuring the corrosion rate, in months, days or years; i is any time before t, in the same unit as t; d(t=i) is the thickness of the corrosion probe at time i, in mm; R R(t) , R C(t) Respectively represent the resistance of the corrosion probe and the temperature compensation element at time t, in ohms; R R(t＝i) , R C(t＝i) They represent the resistance of the corrosion probe and the temperature compensation element at time i, respectively, in ohms.

[0008] As a preferred solution of the present invention, the data monitoring module is composed of a corrosion probe voltage measurement unit, a temperature compensation element voltage measurement unit and a current measurement unit. The corrosion probe voltage measurement unit and the temperature compensation element voltage measurement unit are respectively connected in parallel with the corrosion probe and the temperature compensation element. The current measurement unit is connected in series in the electrical circuit composed of the corrosion probe and the temperature compensation element, and is used to monitor the current and voltage flowing through the corrosion probe and the temperature compensation element.

[0009] As a preferred solution of the present invention, the data monitoring module is connected to the data acquisition module, the data acquisition module uses an embedded microprocessor to record the current value and voltage value measured by the data monitoring module, and the data acquisition module is connected to the control module.

[0010] As a preferred solution of the present invention, the control module is divided into B gear and C gear, which are used to set the corrosion rate test mode, and the data processing module is installed behind the control module; there is a periodic wake-up element in the channel where the B gear is located, and its function is to periodically wake up the data processing module and the real-time positioning and communication module, and calculate the corrosion rate of the corrosion probe during the sleep time for long-term monitoring; the wake-up cycle of the periodic wake-up element can be set manually or by remote control.

[0011] As a preferred solution of the present invention, there is an instant wake-up element in the channel where the C gear is located, which is turned on or off according to the instructions sent by the intelligent cathodic protection system, and the corrosion rate from the time the instant wake-up element is turned on to the time it is turned off is calculated for short-term monitoring.

[0012] As a preferred solution of the present invention, the data processing module is composed of a processing unit, a computing unit and a communication unit, which are connected in sequence behind the control module; the processing unit adopts a microprocessor to filter the recorded voltage value to eliminate the influence of surrounding interference and convert the received current and voltage signals into data types that can be recognized by the computing unit. The computing unit receives the current and voltage transmitted by the processing unit to calculate the resistance values ​​of the corrosion probe and the temperature compensation unit respectively, and calculates the corrosion rate based on their resistance values.

[0013] As a preferred solution of the present invention, the communication unit adopts one or more of GPRS interface, NB-IOT interface, Bluetooth interface, and RS485 interface, and the communication unit is connected to the real-time positioning and communication module.

[0014] As a preferred solution of the present invention, the real-time positioning and communication module is composed of a positioning unit, a communication unit and a data storage unit. The positioning unit is used to quickly determine the position of the corrosion rate detector for easy maintenance and replacement. The communication mode of the communication unit is Beidou communication, Bluetooth communication or a combination of both. Its function is to synchronize the data of the corrosion rate automatic test system and transmit the corrosion rate data, corrosion amount data, power module remaining power data, position data, time data, etc. to the intelligent cathodic protection system. After receiving the message sent by the communication unit, the intelligent cathodic protection system will send a receipt to the communication unit. After receiving the receipt, the communication unit will automatically delete the sent data. If no receipt is received, the communication unit will store the data in the data storage unit and continue to send the data at the next startup until the receipt is received.

[0015] The beneficial effects of the present invention are as follows: the present invention can realize long-term or short-term automatic testing of the corrosion amount of the corrosion probe, automatically calculate the corrosion rate, and transmit the test results back to the intelligent cathodic protection system in real time, thereby ensuring the accuracy of the corrosion rate measurement time and reducing personnel labor. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention is a schematic diagram of the structure of a natural gas pipeline corrosion rate automatic testing system according to an embodiment of the present invention.

[0017] Figure 2 It is a test flow chart of an embodiment of the present invention.

[0018] The figure numerals are as follows: 1. Pipeline, 2. Corrosion rate metering module, 3. Data monitoring module, 4. Data acquisition module, 5. Control module, 6. Data processing module, 7. Real-time positioning and communication module, 8. Power supply module, 9. Intelligent cathodic protection system, 21. Corrosion probe, 22. Temperature compensation element, 31. Corrosion probe voltage measurement unit, 32. Temperature compensation element voltage measurement unit, 33. Current measurement unit, 51. Periodic wake-up element, 52. Instant wake-up element, 61. Processing unit, 62. Calculation unit, 63. Communication unit, 71. Positioning unit, 72. Communication unit, 73. Data storage unit. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] Example:

[0022] like Figure 1-Figure 2 As shown, the present invention provides an automatic testing system for corrosion rate of a natural gas pipeline, comprising a corrosion rate metering module 2, a data monitoring module 3, a data acquisition module 4, a control module 5, a data processing module 6, a real-time positioning and communication module 7 and a power module 8; the power module 8 adopts a rechargeable battery to provide power for the corrosion rate measurement module 2, the data monitoring module 3, the data acquisition module 4, the control module 5, the data processing module 6, the real-time positioning and communication module 7, wherein the corrosion rate metering module 2 and the data monitoring module 3 are located in one electrical circuit, and the data acquisition module 4, the control module 5, the data processing module 6, the real-time positioning and communication module 7 are located in another electrical circuit, which can be charged by solar energy at ordinary times and can be replaced when necessary.

[0023] Among them, the corrosion rate metering module 2 is composed of a corrosion probe 21 and a temperature compensation element 22. The burial depth of the corrosion probe 21 is the same as that of the pipeline 1. The corrosion probe 21 and the temperature compensation element 22 are connected in series in the same circuit. The function of the corrosion probe 21 is to detect corrosion in the soil and then measure the corrosion rate based on the resistance change. The function of the temperature compensation element 22 is to prevent temperature changes from affecting the resistivity of the corrosion probe 21 and thus affecting the calculation result of the corrosion rate.

[0024] Specifically, the data monitoring module 3 is composed of a corrosion probe voltage measurement unit 31, a temperature compensation element voltage measurement unit 32, and a current measurement unit 33. The corrosion probe voltage measurement unit 31 and the temperature compensation element voltage measurement unit 32 are respectively connected in parallel with the corrosion probe 21 and the temperature compensation element 22. The current measurement unit 33 is connected in series in the electrical circuit composed of the corrosion probe 21 and the temperature compensation element 22, and is used to monitor the current and voltage flowing through the corrosion probe 21 and the temperature compensation element 22.

[0025] The data acquisition module 4 is connected to the data monitoring module 3 , and uses an embedded microprocessor to record the current value and voltage value measured by the data monitoring module 3 . The data acquisition module 4 is connected to the control module 5 .

[0026] The control module 5 is divided into B gear and C gear, which are used to set the corrosion rate test mode. There is a periodic wake-up element 51 in the channel where the B gear is located. Its function is to periodically wake up the data processing module 6 and the real-time positioning and communication module 7, and calculate the corrosion rate of the corrosion probe 21 during the sleep time for long-term monitoring. The wake-up cycle of the periodic wake-up element 51 can be set manually or by remote control; there is an instant wake-up element 52 in the channel where the C gear is located, which is turned on or off according to the instructions sent by the intelligent cathodic protection system 9, and the corrosion rate from the time the instant wake-up element 52 is turned on to the time it is turned off is calculated for short-term monitoring. The data processing module 6 is installed after the control module 5.

[0027] The data processing module 6 is composed of a processing unit 61, a calculation unit 62 and a communication unit 63, which are connected in sequence to the rear of the control module 5, wherein the processing unit 61 adopts a microprocessor to filter the recorded voltage value to eliminate the influence of surrounding interference; the calculation unit 62 receives the current and voltage transmitted by the processing unit 61 to calculate the resistance values ​​of the corrosion probe 21 and the temperature compensation unit 22 respectively, and calculates the corrosion rate according to their resistance values; the communication unit 63 adopts one or more of a GPRS interface, a NB-IOT interface, a Bluetooth interface, and an RS485 interface, and the communication unit 63 is connected to the real-time positioning and communication module 7.

[0028] The real-time positioning and communication module 7 is mainly composed of a positioning unit 71 and a communication unit 72. The positioning unit 71 is used to quickly determine the position of the corrosion rate detector for easy maintenance and replacement. The communication mode of the communication unit 72 is Beidou communication, Bluetooth communication, or a combination of the two. Its function is to synchronize the data of the corrosion rate automatic test system, and transmit the corrosion rate data, corrosion amount data, power module remaining power data, location data, time data, etc. to the intelligent cathodic protection system 9. After receiving the message sent by the communication unit 72, the intelligent cathodic protection system 9 will send a receipt to the communication unit 72. After receiving the receipt, the communication unit 72 will automatically delete the sent data. If no receipt is received, the communication unit 72 will store the data in the data storage unit 73, and continue to send this data at the next startup until the receipt is received.

[0029] Corrosion probe 21 resistance value calculation formula: The calculation formula of the resistance value of the temperature compensation element 22 is: Corrosion rate calculation formula: Among them, R C is the resistance of the corrosion probe 21, in ohms; U C is the voltage across the corrosion probe 21, in volts; I is the current flowing through the corrosion probe 21 and the temperature compensation element 22, in amperes; R R is the resistance of the temperature compensation element 22, in ohms; U R is the voltage across the temperature compensation element 22, in volts; a is the corrosion rate, in mm / (time), the time unit is consistent with the unit of t on the right side of the equation; t is the time for measuring the corrosion rate, in months, days or years; i is any time before t, in the same unit as t; d(t=i) is the thickness of the corrosion probe at time i, in mm; R R(t) , R C(t) They represent the resistance of the corrosion probe 21 and the temperature compensation element 22 at time t, in ohms; R R(t＝i) , R C(t＝i) They respectively represent the resistance of the corrosion probe 21 and the temperature compensation element 22 at time i, in ohms.

[0030] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention; therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0031] Although this article uses more of the following terms: 1. pipeline, 2. corrosion rate metering module, 3. data monitoring module, 4. data acquisition module, 5. control module, 6. data processing module, 7. real-time positioning and communication module, 8. power module, 9. intelligent cathodic protection system, 21. corrosion probe, 22. temperature compensation element, 31. corrosion probe voltage measurement unit, 32. temperature compensation element voltage measurement unit, 33. current measurement unit, 51. periodic wake-up element, 52. instant wake-up element, 61. processing unit, 62. calculation unit, 63. communication unit, 71. positioning unit, 72. communication unit, 73. data storage unit, etc., it does not exclude the possibility of using other terms. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. A natural gas pipeline corrosion rate automatic testing system, characterized by: The invention comprises a corrosion rate metering module (2), a data monitoring module (3), a data acquisition module (4), a control module (5), a data processing module (6), a real-time positioning and communication module (7) and a power module (8); the power module (8) adopts a rechargeable battery to provide power for the corrosion rate metering module (2), the data monitoring module (3), the data acquisition module (4), the control module (5), the data processing module (6), the real-time positioning and communication module (7); the corrosion rate metering module (2) and the data monitoring module (3) are located in one electric circuit, and the data acquisition module (4), the control module (5), the data processing module (6), the real-time positioning and communication module (7) are located in another electric circuit; the corrosion rate metering module (2) is composed of a corrosion probe (21) and a temperature compensation element (22), and the corrosion probe (21) and the temperature compensation element (22) are connected in series in the same circuit; the burial depth of the corrosion probe (21) is the same as that of the pipeline (1); the calculation formula of the resistance value of the corrosion probe (21) is: The calculation formula of the resistance value of the temperature compensation element (22) is: Corrosion rate calculation formula: in, R C is the resistance of the corrosion probe in ohms; U C is the voltage across the corrosion probe (21), in volts; I is the current flowing through the corrosion probe (21) and the temperature compensation element (22), in amperes; R R is the resistance of the temperature compensation element (22), in ohms; U R is the voltage across the temperature compensation element (22), in volts; a is the corrosion rate, in mm / time, the time unit is consistent with the unit of t on the right side of the equation; t is the time for measuring the corrosion rate, in months, days or years; i is any time before t, in the same unit as t; d(t=i) is the thickness of the corrosion probe at time i, in mm; R R(t) , R C(t) Respectively represent the resistance of the corrosion probe (21) and the temperature compensation element (22) at time t, in ohms; R R(t＝i) , R C(t＝i) They respectively represent the resistance of the corrosion probe (21) and the temperature compensation element (22) at time i, in ohms.

2. The natural gas pipeline corrosion rate automatic testing system according to claim 1 is characterized by: The data monitoring module (3) is composed of a corrosion probe voltage measurement unit (31), a temperature compensation element voltage measurement unit (32) and a current measurement unit (33); the corrosion probe voltage measurement unit (31) and the temperature compensation element voltage measurement unit (32) are respectively connected in parallel with the corrosion probe (21) and the temperature compensation element (22); the current measurement unit (33) is connected in series in an electrical circuit composed of the corrosion probe (21) and the temperature compensation element (22), and is used to monitor the current and voltage flowing through the corrosion probe (21) and the temperature compensation element (22).

3. The natural gas pipeline corrosion rate automatic testing system according to claim 2 is characterized by: The data monitoring module (3) is connected to a data acquisition module (4), the data acquisition module (4) uses an embedded microprocessor to record the current value and voltage value measured by the data monitoring module (3), and the data acquisition module (4) is connected to a control module (5).

4. The natural gas pipeline corrosion rate automatic testing system according to claim 3 is characterized by: The control module (5) is divided into a B gear and a C gear, which are used to set the corrosion rate test mode. A data processing module (6) is installed behind the control module (5); a periodic wake-up element (51) is provided in the channel where the B gear is located, and its function is to periodically wake up the data processing module (6) and the real-time positioning and communication module (7) to calculate the corrosion rate of the corrosion probe (21) during the sleep time for long-term monitoring; the wake-up period of the periodic wake-up element (51) is set manually or by remote control.

5. The natural gas pipeline corrosion rate automatic testing system according to claim 4 is characterized by: The channel where the C gear is located has an instant wake-up element (52), which is turned on or off according to the instruction sent by the intelligent cathode protection system (9), and the corrosion rate during the period from when the instant wake-up element (52) is turned on to when it is turned off is calculated for short-term monitoring.

6. A natural gas pipeline corrosion rate automatic testing system according to claim 5, characterized in that: The data processing module (6) is composed of a processing unit (61), a calculation unit (62) and a communication unit (63), and the processing unit (61), the calculation unit (62) and the communication unit (63) are connected in sequence to the rear of the control module (5); the processing unit (61) uses a microprocessor to filter the recorded voltage value to eliminate the influence of surrounding interference and convert the received current and voltage signals into data types that can be recognized by the calculation unit; the calculation unit (62) receives the current and voltage transmitted by the processing unit (61) to calculate the resistance values ​​of the corrosion probe (21) and the temperature compensation element (22) respectively, and calculates the corrosion rate based on their resistance values.

7. A natural gas pipeline corrosion rate automatic testing system according to claim 6, characterized in that: The communication unit (63) uses one or more of a GPRS interface, a NB-IOT interface, a Bluetooth interface, and an RS485 interface, and the communication unit (63) is connected to a real-time positioning and communication module (7).

8. The natural gas pipeline corrosion rate automatic testing system according to claim 7 is characterized by: The real-time positioning and communication module (7) is composed of a positioning unit (71), a communication unit (72) and a data storage unit (73). The positioning unit (71) is used to quickly determine the position of the corrosion rate detector for easy maintenance and replacement. The communication unit (72) uses Beidou communication, Bluetooth communication or a combination of the two. Its function is to synchronize the data of the corrosion rate automatic test system and transmit the corrosion rate data, corrosion amount data, power module remaining power data, position data, time data, etc. to the intelligent cathodic protection system (9). After receiving the message sent by the communication unit (72), the intelligent cathodic protection system (9) will send a receipt to the communication unit (72). After receiving the receipt, the communication unit (72) will automatically delete the sent data. If no receipt is received, the communication unit (72) will store the data in the data storage unit (73) and continue to send the data at the next startup until the receipt is received.

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