CN212080884U - Real-time online detection device for erosion of magnetic conduction pipe column - Google Patents
Real-time online detection device for erosion of magnetic conduction pipe column Download PDFInfo
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- CN212080884U CN212080884U CN202020591785.5U CN202020591785U CN212080884U CN 212080884 U CN212080884 U CN 212080884U CN 202020591785 U CN202020591785 U CN 202020591785U CN 212080884 U CN212080884 U CN 212080884U
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Abstract
The utility model discloses a real-time online detection device for erosion of a magnetic conduction pipe column, which structurally comprises m induction coils arranged on the outer wall of the magnetic conduction pipe column, wherein each induction coil is connected with a signal processing module; the signal processing module comprises a multi-channel analog switch, a programmable amplifier, an excitation source amplifier, a programmable filter, an amplitude phase detector and a microprocessor; the number of channels of the multi-channel analog switch is more than or equal to the number m of the induction coils, moving contacts of the corresponding channels of the two groups of multi-channel analog switches are connected in parallel and then are respectively connected with each induction coil, and static contacts of the multi-channel analog switches are respectively connected with the programmable amplifier and the excitation source amplifier; the programmable amplifier is sequentially connected with the programmable filter, the amplitude phase detector and the microprocessor; the amplitude phase detector is also connected to the driver amplifier. The utility model discloses a detection device can carry out real-time on-line measuring to oil gas pipeline, need not artificial intervention, practices thrift and patrols and examines the cost.
Description
Technical Field
The utility model relates to an oil gas pipeline detects technical field, in particular to magnetic conduction tubular column erosion real-time on-line measuring device based on magnetic field induction range and phase change.
Background
The service age of pipelines built in the 70 th century of China is close to or more than 40 years, and the aging is serious. Once an accident occurs, the oil and gas transmission pipeline has wide influence range and serious consequences. The pipeline detection and safety early warning technology is an important means for guaranteeing the safe operation of the oil and gas pipeline. The conventional nondestructive testing technology comprises the following steps: ultrasonic detection, ray detection, magnetic powder detection, penetration detection and eddy current detection. The detection technologies applied to the on-line detection of long-distance pipelines have defects which are difficult to compensate, such as: the thickness of the pipeline metal layer with the internal scaling and the external anticorrosive coating is difficult to accurately detect by ultrasonic waves; the manually moved ultrasonic probe cannot realize buried pipeline detection and on-line real-time detection. The radioactive source is used for ray detection, so that the damage to people is great, people are irradiated due to careless operation, and the probability of leukemia is increased. The magnetic powder detection has high requirements on the surface smoothness of a detected piece, high requirements on the technology and experience of detection personnel, small detection range and low detection speed. Penetration testing cannot detect a thinned, unperforated pipe. Conventional eddy current testing can only detect surface and near-surface defects of conductive materials, and the testing result is also easily interfered by the materials and other factors.
Moreover, the conventional detection methods described above all have the following problems: (1) in part of detection technologies, the oil and gas pipeline needs to be shut down in advance when detection is carried out, and the oil and gas pipeline cannot normally convey oil and gas in the detection process. (2) Most of the detection methods are suitable for periodically detecting the oil and gas pipelines and cannot carry out real-time online detection. (3) The pipeline is detected regularly, because whether the pipeline has problems or not is not known, all pipelines need to be detected, and the detection result can be that the pipeline is intact, so that a great amount of manpower and material resources are wasted. (4) The pipelines buried deeply underground, in the field of wasteland and erected at high altitude are inconvenient to detect.
Disclosure of Invention
The utility model discloses a need to the conventional detection method existence of current pipeline detects the pipeline after shutting down, can not carry out real-time on-line measuring to the pipeline, is not suitable for bury deeply underground, is in the field and the high altitude of wasteland and erects these pipeline detection scheduling problems of installation, provides a magnetic conduction tubular column erosion real-time on-line measuring device based on magnetic field induction range and phase change.
The utility model provides a real-time on-line measuring device of magnetic conduction tubular column erosion, include: m induction coils fixedly arranged on the outer wall of the magnetic conduction pipe column are sleeved, and m is more than or equal to 2. The induction coils are installed on the magnetic conduction pipe column at equal intervals. The induction coil is an air coil wound by enameled wire materials, the winding direction is the same, and the number of winding turns is more than 100. Each induction coil is connected with the signal processing module and can be used as an exciting coil or a receiving coil. During detection, one and only one induction coil is used as an exciting coil, and the rest induction coils are used as receiving coils.
The signal processing module comprises a multi-channel analog switch, a programmable amplifier, an excitation source amplifier, a programmable filter, an amplitude phase detector and a microprocessor. The multi-channel analog switch is a multi-selection one analog switch. The number of channels of the multi-channel analog switch is more than or equal to the number m of the induction coils. The multichannel analog switch is composed of two groups of independent analog switches, the two groups of multichannel analog switches are connected with each induction coil after corresponding channel moving contacts are connected in parallel, the static contact of one group of multichannel analog switch is connected with the programmable amplifier, and the static contact of the other group of multichannel analog switch is connected with the excitation source amplifier. The programmable amplifier is sequentially connected with the programmable filter, the amplitude phase detector and the microprocessor; the amplitude phase detector is also connected to the driver amplifier. The multi-channel analog switch, the programmable amplifier, the driving source amplifier, the programmable filter, the amplitude phase detector and the microprocessor are all contained in the signal processing module.
The programmable amplifier adopts a low-noise instrument amplifier with differential input, the amplification gain is adjustable in a range of 1-10000 times, and the amplification gain is adjusted through analog voltage, or through a digital interface, or through back-end feedback automatic adjustment.
The programmable filter is a switched capacitor filter, the center frequency is adjustable from 0.1Hz to 100KHz, and the order is more than or equal to 4. The programmable filter can be programmed by the microprocessor to work in both a band-pass filtering mode and a low-pass filtering mode.
The amplitude phase detector is a received signal amplitude and phase detector, and amplitude and phase detection results are output as digital signals.
The microprocessor is a low-power-consumption microprocessor, and any one or more of ADC, SPI, DAC, UART, IIC and GPIO is/are arranged on the microprocessor.
Compared with the prior art, the utility model discloses an useful part lies in:
(1) the utility model discloses a detection device adopts magnetic field measurement, and the environmental protection is radiationless, and non-contact measures, and detection device installs all the time at the pipeline surface, does not destroy the tubular column structure, does not harm the anticorrosive coating, surveys the magnetic conduction metal material damage, does not receive scale deposit and anticorrosive coating influence.
(2) The oil-gas pipeline does not need to be shut down when being detected, normal conveying work of the oil-gas pipeline is not influenced, real-time online detection is achieved, manual intervention is not needed, and inspection cost is saved.
(3) The detection is convenient for the pipelines which are deeply buried underground, are positioned in the field of wasteland and are erected and installed at high altitude.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Drawings
Fig. 1 is a schematic view of the installation structure of the real-time online detection device for erosion of the magnetic conduction pipe column of the present invention.
Fig. 2 is a schematic structural diagram of a signal processing module.
Reference numbers in the figures: 1. 2 and 3 … m are induction coil numbers, 11-magnetic conduction pipe column, 12-induction coil, 13-signal processing module, 14-multichannel analog switch, 15-programmable amplifier, 16-excitation source amplifier, 17-programmable filter, 18-amplitude phase detector and 19-microprocessor.
Detailed Description
The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are presented herein only to illustrate and explain the present invention, and not to limit the present invention.
As shown in fig. 1 and 2, the utility model provides a real-time on-line measuring device of magnetic conduction tubular column erosion, include: m induction coils 12 fixedly installed on the outer wall of the magnetic conduction pipe column 11 are sleeved, and are numbered 1, 2 and 3 … m in sequence, wherein m is larger than or equal to 2. All induction coils 12 are installed on the magnetic conduction pipe column 11 at equal intervals. The induction coil 12 is an air-core coil wound by an enameled wire material, the winding direction is the same, and the winding number is more than 100 turns. Each induction coil 12 is connected with the signal processing module 13, and each induction coil 12 can be used as an excitation coil or a receiving coil. In the detection operation, there is one and only one induction coil 12 as an excitation coil, and the rest induction coils 12 as receiving coils.
The signal processing module 13 comprises a multi-channel analog switch 14, a programmable amplifier 15, a driver amplifier 16, a programmable filter 17, an amplitude phase detector 18 and a microprocessor 19 which are arranged inside the signal processing module. The multi-channel analog switch 14 is a one-out-of-many analog switch, and the preferable on-resistance is less than 1 ohm. The number of channels of the multi-channel analog switch 14 is more than or equal to the number m of the induction coils. The multi-channel analog switch 14 is composed of two groups of independent analog switches, the moving contacts of the corresponding channels of the two groups of multi-channel analog switches 14 are connected in parallel and then are respectively connected with each induction coil 12, the static contact of one group of multi-channel analog switches 14 is connected with a programmable amplifier 15, and the static contact of the other group of multi-channel analog switches 14 is connected with an excitation source amplifier 16. Preferably, the multi-channel analog switch 14 may be a low on-resistance analog switch of ISL84781 model number, available from rejsas electronics ltd (Renesas).
The programmable amplifier 15 is connected with a programmable filter 17, an amplitude phase detector 18 and a microprocessor 19 in sequence; the amplitude phase detector 18 is also connected to the driver amplifier 16. Preferably, the driver amplifier is a Texas Instruments model TLV4120 power operational amplifier.
The programmable amplifier 15 adopts a low-noise instrument amplifier with differential input, the amplification gain is adjustable by 1-10000 times, and the amplification gain is adjusted by analog voltage, or adjusted by a digital interface, or automatically adjusted by back end feedback. Preferably, the programmable amplifier is a low power consumption programmable broadband amplifier having model AD8338 from adeno semiconductor technologies, Inc.
The programmable filter 17 is a switched capacitor filter, the center frequency is adjustable from 0.1Hz to 100KHz, and the order is more than or equal to 4. Programmable filter 17 is programmable by the microprocessor to operate in either a band pass or a low pass filtering mode. The programmable filter can be programmed by the microprocessor to keep the center frequency of the band-pass filter consistent with the frequency of the excitation signal. A high order filter model LTC1064 from asian semiconductor technologies, Inc.
The amplitude phase detector 18 is a received signal amplitude and phase detector, and the amplitude and phase detection result is output as a digital signal. The amplitude phase detector is preferably an impedance converter network analysis processing chip of model AD5933 of adno semiconductor technologies, Inc.
The microprocessor 19 adopts a low-power-consumption microprocessor, and any one or more of ADC, SPI, DAC, UART, IIC and GPIO is/are arranged on the microprocessor. The microprocessor is preferably a high performance ultra low power microprocessor model MSP430FG4270 from Texas Instruments.
The method for detecting the real-time online detection device for the erosion of the magnetic conduction pipe column comprises the following steps:
step S1, calculating the induction signal amplitude ULThe formula is as follows:
wherein R ism、ImSatisfies the following formula:
l is the inductance of the induction coil, and the unit H satisfies the following formula:
c is the distributed capacitance of the induction coil, and the unit F satisfies the following formula:
in the above formula,. mu.aEffective magnetic permeability without dimension; ω is the excitation signal angular frequency, ω is 2 pi f, f is the excitation signal frequency, in Hz; mu.s0Is the vacuum magnetic permeability, unit H/m; mu.srThe relative magnetic conductivity of the pipe column material is dimensionless; d is the outer diameter of the tubular column in m; n is the number of turns of the induction coil; l is the length of a single-section pipe column in m; lωThe winding width of the induction coil is in m; sigma is the conductivity of the tubular column material, S/m; m is mutual inductance between the exciting coil and the receiving coil, and the value of a unit H is between L/200 and L; rLEquivalent load resistance of a receiving coil voltage measuring circuit is in unit omega; u shapeIIs the excitation signal voltage amplitude, in units of V; r is the direct current resistance of the induction coil and has the unit of omega; n is the number of winding layers of the induction coil;0is the vacuum dielectric constant, in F/m;rthe relative dielectric constant of the insulating varnish of the enameled wire is dimensionless; is the outer diameter of the enameled wire in m; d' is the enameled wire medium thickness in m.
Firstly, setting a coil installation space DC0.8 × L (this is an empirical formula), the induction signal amplitude U is substituted with 100 coil turns N, L/200M, and 0.1 f, as well as other actual parameters of the column, coil, and measurement circuitLIn the calculation formula, the induction signal amplitude U is finally calculatedL. If U isLIf the value is greater than or equal to 100 μ V, the set of parameters is used as formal installation parameters of the detection device. If U isLIf the current is less than 100 mu V, gradually increasing the number of turns of the coil or shortening the installation distance of the coil, and calculating ULUp to ULAnd the set of parameters is taken as the formal installation parameters of the detection device when the set of parameters is larger than 100 mu V.
Step S2, starting an initialization system through an external instruction after the device is installed; the method comprises the following specific steps:
and S21, adjusting the multi-channel analog switch to use one induction coil as an exciting coil and another adjacent induction coil as a receiving coil. The specific method comprises the following steps: all induction coils are numbered as 1, 2 and 3 … m in sequence, a microprocessor switches one group of multi-channel analog switches through IO (input/output), so that the induction coil No. 1 is connected with the output of an excitation source amplifier, and the induction coil No. 1 is used as an excitation coil; the microprocessor switches another group of multi-channel analog switches through IO (input/output) to enable the No. 2 induction coil to be connected with the input of the programmable amplifier, and the No. 2 induction coil is used as a receiving coil at the moment.
And S22, determining the optimal working frequency. The specific method comprises the following steps: the microprocessor controls the amplitude phase detector to output an initial excitation signal with the frequency of 0.1Hz and drives the excitation coil to generate an alternating magnetic field; the programmable filter is adjusted to a low-pass filtering mode with the cut-off frequency of 100 KHz; receiving the induction signal by the receiving coil, adjusting the amplifier gain of the programmable amplifier to enable the amplitude of the received signal to be close to that of the excitation signal, enabling the deviation to be less than 10%, recording the initial excitation frequency, receiving the signal amplitude and amplifying the gain; gradually increasing the excitation frequency, when the amplitude of the received signal is greater than 10% of the excitation signal, adjusting the gain of the amplifier of the programmable amplifier to make the amplitude of the received signal less than 10% of the excitation signal, achieving the purpose of automatic gain control, updating the recorded initial excitation frequency, the amplitude of the received signal and the amplification gain; and circularly increasing the excitation frequency until the frequency reaches 100KHz, stopping the frequency sweeping step, and storing the excitation frequency recorded in the RAM area of the microprocessor into a Flash or EEPROM area of the microprocessor as the optimal working frequency at the moment. The optimum operating frequency is the frequency at which the received amplitude is maximum. The optimum operating frequency is limited to between 0.1Hz-100KHz, and cannot be higher than 100 KHz.
S23, setting the frequency of the excitation signal as the optimal working frequency value in the step S22, adjusting the programmable filter to be in a band-pass filtering mode, and adjusting the gain of the amplifier of the programmable amplifier to enable the amplitude of the received signal to be less than 10% of the amplitude of the excitation signal; switching another induction coil as an exciting coil and the other coils as receiving coils, and establishing an array P [ m:0 ] in the microprocessor][m-1:0]When the induction coil with the number m is used as an exciting coil, phase values received by the other induction coils are stored in an array P, and after all exciting receiving coil data are obtained, the array P is stored in a Flash or EEPROM area of the microprocessor; the initialization system steps are completed. The phase value
The following formula is satisfied:
in the formula, Rm、ImThe meaning of the term is the same as R in step S1m、ImThe same is true.
Step S3, after the system initialization step is completed, the system enters a working state, the magnetic flux leakage quantity of the magnetic conduction pipe column changes after the magnetic conduction pipe column is eroded, and the exciting coils are continuously rotatedAnd acquiring phase values of all induction coils
And comparing the phase value with the phase value recorded by the array P, judging that the erosion is serious when the phase value is more than 1%, and giving an early warning to the outside through a microprocessor.
The steps of switching the exciting coil and the receiving coil are as follows: when the No. 1 induction coil is used as an exciting coil, the No. 2, No. 3, No. 4 to No. m induction coils are used as receiving coils; when the No. 2 induction coil is used as an exciting coil, the No. 1, No. 3, No. 4 to No. m induction coils are used as receiving coils; and so on; the measurement dead zone can be eliminated by switching the exciting coil and the receiving coil, and the erosion position can be determined.
To sum up, the utility model provides a magnetic conduction tubular column erosion real-time on-line measuring device based on magnetic field response range and phase change has overcome the needs that current conventional detection method of pipeline exists and has detected after shutting down the pipeline, can not carry out real-time on-line measuring, is not suitable for burying deeply underground, is in the field and the high altitude of wasteland and erects these pipeline detection scheduling problems of installation. The utility model discloses a detection device practicality is stronger, need not artificial intervention, practices thrift and patrols and examines the cost.
The above description is only a preferred embodiment of the present invention, and the present invention is not limited to the above description, and although the present invention has been disclosed with the preferred embodiment, it is not limited to the present invention, and any skilled person in the art can make modifications or changes equivalent to the equivalent embodiment without departing from the scope of the present invention, but all the modifications, equivalent changes and modifications of the above embodiments by the technical spirit of the present invention still fall within the scope of the present invention.
Claims (8)
1. The utility model provides a real-time on-line measuring device of magnetic conduction tubular column erosion which characterized in that includes: the device comprises a magnetic conduction pipe column, a signal processing module, an excitation coil and a receiving coil, wherein m induction coils fixedly installed on the outer wall of the magnetic conduction pipe column are sleeved, m is more than or equal to 2, the induction coils are hollow coils wound by enameled wires, the winding directions are the same, the number of winding turns is more than 100, each induction coil is connected with the signal processing module and can be used as the excitation coil or the receiving coil, only one induction coil is used as the excitation coil, and the rest induction coils are used as the receiving coils during detection;
the signal processing module comprises a multi-channel analog switch, a programmable amplifier, an excitation source amplifier, a programmable filter, an amplitude phase detector and a microprocessor, wherein the number of channels of the multi-channel analog switch is more than or equal to the number m of induction coils, the multi-channel analog switch is composed of two groups of independent analog switches, moving contacts of the two groups of analog switches corresponding to the channels are connected in parallel and then are respectively connected with each induction coil, a static contact of one group of multi-channel analog switches is connected with the programmable amplifier, and a static contact of the other group of multi-channel analog switches is connected with the excitation source amplifier; the programmable amplifier is sequentially connected with the programmable filter, the amplitude phase detector and the microprocessor; the amplitude phase detector is also connected to the driver amplifier.
2. The real-time online erosion detection device for a magnetically conductive pipe string as claimed in claim 1, wherein the induction coils are fixedly mounted on the magnetically conductive pipe string at equal intervals.
3. The apparatus according to claim 1, wherein the programmable amplifier is a differential input low noise instrumentation amplifier, the amplification gain is adjustable by 1-10000 times, and the amplification gain is adjusted by analog voltage, digital interface, or back-end feedback.
4. The real-time online erosion detection device for a magnetic conduction pipe column according to claim 1, wherein the programmable filter is a switched capacitor filter, the center frequency is adjustable from 0.1Hz to 100KHz, and the order is greater than or equal to 4.
5. The apparatus for real-time online detection of erosion of a magnetic permeable pipe string as claimed in claim 4, wherein the programmable filter is programmable by the microprocessor to operate in either a band-pass filtering mode or a low-pass filtering mode.
6. The real-time online erosion detection device for a magnetic conduction pipe string as claimed in claim 1, wherein the multi-channel analog switch is a one-out-of-many analog switch.
7. The real-time online detection device for erosion of a magnetic conduction pipe column according to claim 1, wherein the microprocessor is a low-power-consumption microprocessor, and any one or more of ADC, SPI, DAC, UART, IIC and GPIO is/are arranged on the microprocessor.
8. The apparatus for real-time on-line detection of erosion of a magnetic conductive pipe string as claimed in claim 1, wherein the amplitude phase detector is a received signal amplitude and phase detector, and the amplitude and phase detection results are output as digital signals.
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| CN111336410A (en) * | 2020-04-20 | 2020-06-26 | 西南石油大学 | Real-time online detection device and method for erosion of magnetic conduction pipe column |
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