Hand-push type hard spot electromagnetic detection trolley

Abstract

The utility model relates to a hand-push type hard spot electromagnetic detection trolley, which belongs to the field of hard spot detection and comprises a detection trolley, a mobile power supply, an upper computer, a measuring circuit and a detection probe, the upper computer is arranged on the detection trolley through a support disc, the mobile power supply and the measuring circuit are arranged on the upper surface of the detection trolley, and the detection probe is arranged at the front end of the detection trolley. One end of the measuring circuit is connected with the detection probe, and the other end is connected with the upper computer; the trolley is simple in structure and convenient and fast to use, online continuous real-time detection can be achieved through electromagnetic nondestructive detection, the detection efficiency can be greatly improved, the workload of workers can be effectively reduced, and the daily hard spot checking and first-aid repair accuracy and the maintenance efficiency are improved.

Description

Technical Field

[0001] The utility model relates to a detection trolley, in particular to a hand-pushed hard point electromagnetic detection trolley, belonging to the field of hard point detection. Background Art

[0002] As the basic material in production and construction, steel materials are widely used in a series of links such as national defense construction, infrastructure construction, industrial production and people's life, which greatly promotes my country's economic development. Among them, pipeline steel is widely used in my country's gas pipelines and oil pipelines.

[0003] However, due to the presence of uneven composition areas, impurities or partial overcooling in the production process of pipeline steel, local hard spots are generated in the steel. The API SPEC 5L specification for pipeline steel pipes has clear requirements for "hard spots": "A single point indentation with a size greater than 50 mm (2.0 in) in any direction and a hardness value greater than 35 HRC, 345 HV10 or 327 HBW should be considered a defect. A hard spot is a defect on a steel plate. It refers to a local area on the surface of the steel plate where the hardness is abnormally higher than that of other normal parts. There is a large gradient change in the hardness near these hard spot areas. During the plastic deformation or service process of the material, stress concentration areas may occur around the hard spots, which will cause cracks on the steel surface. Figure 1 As shown, it seriously affects the service safety of the pipeline.

[0004] At present, the EU has stipulated the surface hardness control requirements of carbon manganese steel for submarine oil and gas pipelines in the industry standard (DNV-OS-F101), and regards hard spots with inner and outer surface hardness values ​​higher than 250HV10 and 275HV10 (production standard value is 200HV10) and size greater than 50 mm in any direction as defects. The EU requires 100% hard spot detection during the manufacturing stage of imported hot-rolled pipeline steel products, so the detection of hard spots is particularly important.

[0005] At present, the hardness of steel is generally tested by destructive testing, such as Vickers hardness, Rockwell hardness, Brinell hardness, Leeb hardness and other destructive physical tests, that is, a section is cut from the parent material for testing after processing. This has the disadvantages of long time consumption, high testing cost, large manpower investment and inability to conduct continuous testing.

[0006] Therefore, developing a detection vehicle that can overcome the above defects has become a technical problem that needs to be solved urgently by those skilled in the art. Utility Model Content

[0007] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a hand-pushed hard point electromagnetic detection trolley with a simple structure, convenient and quick use, and the ability to achieve online continuous real-time detection through electromagnetic non-destructive testing, which can greatly improve the detection efficiency, effectively reduce the workload of personnel, and improve the accuracy and maintenance efficiency of daily hard point inspection and repair.

[0008] In order to solve the above technical problems, the utility model provides a hand-pushed hard point electromagnetic detection trolley, including a detection trolley, a mobile power supply, a host computer, a measuring circuit and a detection probe. The host computer is arranged on the detection trolley through a supporting plate, the upper surface of the detection trolley is provided with a mobile power supply and a measuring circuit, and the front end of the detection trolley is provided with a detection probe, one end of the measuring circuit is connected to the detection probe, and the other end is connected to the host computer;

[0009] The detection probe includes a coil probe and a probe support frame. One end of the probe support frame is arranged on the detection trolley, and the other end is provided with a coil probe. The probe support frame includes a probe support plate, a probe swing plate and a probe box. The cross-section of the probe support plate is an L-shaped structure. The vertical section of the probe support plate is connected to the detection trolley. The horizontal section of the probe support plate is concave to form an installation groove. The probe swing plate is hinged in the installation groove. The probe swing plate is provided with a probe box. Through holes are provided at corresponding positions on the probe box and the probe swing plate. Coil probes are provided in the through holes. The coil probe faces the ground for detection.

[0010] The technical solution further defined in the utility model is:

[0011] Furthermore, in the aforementioned hand-pushed hard point electromagnetic detection cart, the detection cart includes a detection cart body, a bracket and a handle. Among the four corners of the bottom of the detection cart body, the two corners located at the front end are respectively provided with universal wheels, and the two corners located at the rear end are respectively provided with directional wheels. A bracket is fixedly provided on the upper surface of the detection cart body, and a host computer is provided on one side of the upper end of the bracket through a support plate, and a handle is provided on the other side. A mobile power supply is provided on the upper surface of the detection cart body, and the mobile power supply is located below the bracket. A measurement circuit is provided on one side of the mobile power supply, and the measurement circuit is located between the mobile power supply and the detection probe.

[0012] Technical effect: The detection trolley of the utility model has a simple structure and is easy to use. It can move on wheels to perform real-time detection and improve efficiency. A handle is set on the bracket for easy operation. The height of the host computer is increased to facilitate viewing and control by the operator, making it more convenient to use.

[0013] In the aforementioned hand-pushed hard point electromagnetic detection trolley, rollers are respectively provided at the four corners of the probe swing plate.

[0014] Technical effect: when the detection probe is detecting the object to be detected, the object may have a protrusion closer to the object, and the roller can move smoothly on the surface of the object, while reducing the friction of the probe support frame in the detection probe, extending the service life, and making it smoother and more convenient to use.

[0015] In the aforementioned hand-pushed hard point electromagnetic detection trolley, at least two support plates are arranged in parallel on the bracket, and the four sides of the support plates extend upward to form fixed edges, and a plurality of through holes are evenly distributed on the support plates.

[0016] Technical effect: The utility model is provided with multiple support plates, which are convenient for the upper computer or other components. At the same time, multiple through holes are provided on the support plates, which are convenient for the heat dissipation of the upper computer or other components and extend their service life. Fixed edges are extended to protect the upper computer and other components in the support plates when the mobile detection trolley is moved, so that they will not slide out of the support plates due to movement, thereby ensuring the stability of work and improving safety.

[0017] In the aforementioned hand-pushed hard point electromagnetic detection trolley, the measurement circuit includes a box and a microprocessor arranged in the box, a programmable waveform generator, a power amplifier, a U-shaped magnetic yoke, a lock-in amplifier, an instrument amplifier, a power detection chip, an A / D acquisition card, a coil probe and a power management module, the coil probe includes a MIP extraction coil and an MBN extraction coil, the MIP extraction coil and the MBN extraction coil are respectively connected with probes, the MIP extraction coil and the MBN extraction coil are respectively wound on the U-shaped magnetic yoke, one end of the MIP extraction coil penetrates the box and is connected to the probe arranged in the probe box, and the other end is connected to the lock-in amplifier, one end of the MBN extraction coil penetrates the box and is connected to the probe arranged in the probe box, and the other end is connected to the power detection chip;

[0018] The microprocessor is connected to a programmable waveform generator to generate low-frequency and high-frequency signals. The low-frequency signal provides excitation for the U-shaped yoke through a power amplifier. The power amplifier is set on one side of the U-shaped yoke corresponding to the winding position of the MIP extraction coil and the MBN extraction coil. The high-frequency signal is amplified by a constant current source composed of the power amplifier to provide excitation for the high-frequency excitation coil to form an alternating magnetic field. The MBN extraction coil receives the signal generated by the magnetic field, amplifies it through an instrument amplifier, and then forms an envelope signal through a power detection chip. The MIP extraction coil signal is modulated and demodulated by a lock-in amplifier to form a MIP signal. The MBN envelope signal and the MIP signal are transmitted to the host computer through an A / D acquisition card for data processing.

[0019] Technical effect: The multi-channel hard spot measurement circuit based on the Barkhausen and incremental magnetic permeability principles of the utility model can greatly improve the hard spot detection efficiency, effectively reduce the workload of personnel, and improve the accuracy and maintenance efficiency of daily hard spot inspection and repair.

[0020] The beneficial effects of the utility model are:

[0021] The principle of multi-frequency eddy current testing:

[0022] During eddy current (EC) testing, the impedance change of the current-carrying coil is caused by the interaction of the generated electromagnetic field with the test specimen. A high-frequency AC voltage is supplied to the excitation coil, which generates an alternating field and induces eddy currents in the test material. The eddy currents in the material depend on the frequency of the AC voltage and the material's electrical conductivity σ and magnetic permeability μ. Changes in the material's microstructure or residual stresses lead to changes in the electrical conductivity σ and magnetic permeability μ, which affect the strength and propagation of the eddy currents. The impedance of the pickup coil also changes, such as Figure 2 shown.

[0023] The probe support plate of the utility model adopts an L-shaped structure, which is convenient for fixed connection with the detection trolley and easy to install and disassemble. The other end can be movably connected with a probe swing plate, so that the coil probe can move slightly, which is suitable for the environment and the detection of hard points in different positions, making the detection more accurate.

[0024] The utility model uses multi-frequency eddy current electromagnetic nondestructive testing technology to reduce the damage of destructive testing; it is equipped with a measuring circuit, and the data can be retained in the host computer for controllable access and later research; multiple detection technology data fusion processing improves the detection quality; a reference state can be obtained through a one-time parameter debugging based on the material to be tested, thereby detecting Rockwell hardness, Brinell hardness, Vickers hardness, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of cracks caused by hard points in steel plates;

[0026] Figure 2 This is the principle diagram of multi-frequency eddy current testing;

[0027] Figure 3 This is a structural schematic diagram of a hand-pushed hard point electromagnetic detection trolley according to an embodiment of the utility model;

[0028] Figure 4 for Figure 3 Schematic diagram of the structure of the middle probe support frame;

[0029] Figure 5 It is the structural diagram of the measuring circuit;

[0030] In the figure: 11-detection trolley body, 12-bracket, 13-handle, 2-mobile power supply, 3-host computer, 4-measuring circuit, 5-support plate, 6-probe support frame, 61-probe support plate, 62-probe swing plate, 63-probe box, 64-roller. DETAILED DESCRIPTION Example 1

[0031] This embodiment provides a hand-pushed hard point electromagnetic detection vehicle, the structure of which is as follows Figure 3-5 As shown, it includes a detection trolley, a mobile power supply 2, a host computer 3, a measuring circuit 4 and a detection probe. The host computer 3 is provided on the detection trolley through a support plate 5, the mobile power supply 2 and the measuring circuit 4 are provided on the upper surface of the detection trolley, and the front end of the detection trolley is provided with a detection probe, one end of the measuring circuit 4 is connected to the normal signal line of the detection probe, and the other end is connected to the normal signal line of the host computer 3;

[0032] The detection probe includes a coil probe and a probe support frame 6. One end of the probe support frame 6 is arranged on the detection trolley, and the other end is provided with a coil probe. The probe support frame 6 includes a probe support plate 61, a probe swing plate 62 and a probe box 63. The cross section of the probe support plate 61 is an L-shaped structure. The vertical section of the probe support plate 61 is connected to the detection trolley. The horizontal section of the probe support plate 61 is concave to form a mounting groove. The mounting groove is hinged with a probe swing plate 62. Rollers 64 are respectively provided at the four corners of the probe swing plate 62. A probe box 63 is provided on the probe swing plate 62. Through holes are provided at corresponding positions on the probe box 63 and the probe swing plate 62. Coil probes are provided in the through holes. The coil probe faces the ground for detection.

[0033] The detection trolley is made of stainless steel, and includes a detection trolley body 11, a bracket 12 and a handle 13. Among the four corners at the bottom of the detection trolley body 11, the two corners at the front end are respectively provided with universal wheels, and the two corners at the rear end are respectively provided with directional wheels. A bracket 12 is fixedly provided on the upper surface of the detection trolley body 11, and at least two support plates 5 are arranged in parallel on the upper and lower sides of the bracket 12. The four sides of the support plate 5 extend upward to form a fixed edge, and a number of through holes are evenly distributed on the support plate. A host computer 7 is provided on one side of the upper end of the bracket 12 through the support plate 5, and a handle 13 is provided on the other side. A mobile power supply 2 is provided on the upper surface of the detection trolley body 11 to power the host computer and other electrical equipment. The mobile power supply 2 is located below the bracket 12, and a measurement circuit 4 is provided on one side of the mobile power supply 2, and the measurement circuit 4 is located between the mobile power supply 2 and the detection probe.

[0034] In this embodiment, the microprocessor uses STM32F103C8t6, the lock-in amplifier uses AD630, the instrument amplifier uses AD620, the power detection chip uses LTC5507, the programmable waveform generator uses AD9833, the power amplifier uses LM3886, and the A / D acquisition card uses DAQ-2208.

[0035] The measuring circuit 4 comprises a box and a microprocessor, a programmable waveform generator, a power amplifier, a U-shaped magnetic yoke, a lock-in amplifier, an instrument amplifier, a power detection chip, an A / D acquisition card, a coil probe and a power management module arranged in the box. The power management module is a switching power supply to supply power to each component, and converts the 220V power supply into +-12v or +-25v or 5v for power supply. The coil probe comprises a MIP extraction coil and an MBN extraction coil. The MIP extraction coil and the MBN extraction coil are respectively connected with probes. The MIP extraction coil and the MBN extraction coil are respectively wound on the U-shaped magnetic yoke. One end of the MIP extraction coil penetrates the box and is connected to the probe arranged in the probe box, and the other end is connected to the lock-in amplifier. One end of the MBN extraction coil penetrates the box and is connected to the probe arranged in the probe box, and the other end is connected to the power detection chip.

[0036] The microprocessor is connected to a programmable waveform generator to generate low-frequency and high-frequency signals. The low-frequency signal provides excitation for the U-shaped yoke through a power amplifier. The power amplifier is set on one side of the U-shaped yoke corresponding to the winding position of the MIP extraction coil and the MBN extraction coil. The high-frequency signal is amplified by a constant current source composed of the power amplifier to provide excitation for the high-frequency excitation coil (the MIP and MBN extraction coils have high-frequency excitation coils inside), forming an alternating magnetic field. The MBN extraction coil receives the signal generated by the magnetic field, amplifies it through an instrument amplifier, and then forms an envelope signal through a power detection chip. The MIP extraction coil signal is modulated and demodulated by a lock-in amplifier to form a MIP signal. The MBN envelope signal and the MIP signal are transmitted to the host computer through an A / D acquisition card for data processing.

[0037] In this embodiment, the host computer is developed using the existing C# programming language. After the application is packaged and generated, it is installed on a laptop computer with a windows operating system as a device end to receive and display the data transmitted by the serial port of the detection circuit.

[0038] In this embodiment, the probe parameters are: inner diameter 6 mm, number of turns 2000, height 10 mm, and wire diameter 0.11 mm.

[0039] In specific implementation, when the system is running, the MBN and MIP extraction coils continuously collect electromagnetic signals from the pipeline steel, the microprocessor sets the excitation frequency, the MBN original signal is enveloped through the power detection circuit, the MIP signal is phase-locked amplified and sent to the host computer together with the MBN signal through the A\D acquisition card, and the host computer performs data analysis, hardness characterization and data storage.

[0040] The utility model designs a MIP extraction coil and a phase-locked amplifier circuit to process the MIP signal, designs an MBN extraction coil and a power detection circuit to obtain the envelope of the MBN original signal, reduces the sampling frequency, can modify the magnetic field frequency through a microprocessor, and uses a multi-channel A / D acquisition card to collect the MIP and MBN signals, which is more convenient to use.

[0041] At present, the hard point detection methods include destructive detection methods and non-destructive detection methods, as shown in Table 1;

[0042] Table 1 Current detection methods

[0043]

[0044] As can be seen from Table 1, compared with other non-destructive testing methods, eddy current testing does not require magnetization of the test piece, and has the advantages of non-contact and high detection efficiency, and is easy to realize automated hardness testing. The utility model adopts eddy current testing to detect the hardness value on the steel plate, and calculates the hard point area of ​​the steel plate through software calculation, which is more convenient and more efficient.

[0045] In addition to the above embodiments, the present invention may also have other implementations. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A hand-pushed hard point electromagnetic detection trolley, characterized in that: The detection trolley comprises a mobile power source (2), a host computer (3), a measuring circuit (4) and a detection probe, wherein the host computer (3) is arranged on the detection trolley via a support plate (5), the mobile power source (2) and the measuring circuit (4) are arranged on the upper surface of the detection trolley, the front end of the detection trolley is provided with the detection probe, one end of the measuring circuit (4) is connected to the detection probe, and the other end is connected to the host computer (3); The detection probe comprises a coil probe and a probe support frame (6); one end of the probe support frame (6) is arranged on the detection trolley, and the other end is provided with the coil probe; the probe support frame (6) comprises a probe support plate (61), a probe swing plate (62) and a probe box (63); the cross section of the probe support plate (61) is an L-shaped structure; the vertical section of the probe support plate (61) is connected to the detection trolley; the horizontal section of the probe support plate (61) is concave to form a mounting groove; the probe swing plate (62) is hinged in the mounting groove; the probe box (63) is provided on the probe swing plate (62); corresponding positions on the probe box (63) and the probe swing plate (62) are provided with through holes; the coil probe is provided in the through holes; the coil probe faces the ground for detection.

2. The hand-pushed hard point electromagnetic detection vehicle according to claim 1 is characterized in that: The detection trolley comprises a detection trolley body (11), a bracket (12) and a handle (13). The two front corners of the bottom of the detection trolley body (11) are respectively provided with universal wheels, and the two rear corners are respectively provided with directional wheels. The bracket (12) is fixedly provided on the upper surface of the detection trolley body (11). The upper end of the bracket (12) is provided with the host computer (3) on one side through the support plate (5), and the handle (13) is provided on the other side. The mobile power supply (2) is provided on the upper surface of the detection trolley body (11), and the mobile power supply (2) is located below the bracket (12). The measurement circuit (4) is provided on one side of the mobile power supply (2), and the measurement circuit (4) is located between the mobile power supply (2) and the detection probe.

3. The hand-pushed hard point electromagnetic detection vehicle according to claim 1 is characterized in that: Rollers (64) are respectively provided at the four corners of the probe swing plate (62).

4. The hand-pushed hard point electromagnetic detection vehicle according to claim 2 is characterized in that: At least two support plates (5) are arranged in parallel on the bracket (12) in an upper and lower manner. The four sides of the support plates (5) extend upward to form fixed edges. The support plates are evenly distributed with a plurality of through holes.

5. The hand-pushed hard point electromagnetic detection vehicle according to claim 1 is characterized in that: The measuring circuit (4) comprises a housing and a microprocessor arranged in the housing, a programmable waveform generator, a power amplifier, a U-shaped magnetic yoke, a lock-in amplifier, an instrumentation amplifier, a power detection chip, an A / D acquisition card, a coil probe and a power management module, wherein the coil probe comprises a MIP extraction coil and an MBN extraction coil, wherein the MIP extraction coil and the MBN extraction coil are respectively connected to probes, wherein the MIP extraction coil and the MBN extraction coil are respectively wound on the U-shaped magnetic yoke, wherein one end of the MIP extraction coil penetrates the housing and is connected to the probe arranged in the probe box, and the other end is connected to the lock-in amplifier, wherein one end of the MBN extraction coil penetrates the housing and is connected to the probe arranged in the probe box, and the other end is connected to the power detection chip; The microprocessor is connected to the programmable waveform generator to generate low-frequency and high-frequency signals. The low-frequency signal provides excitation for the U-shaped magnetic yoke through a power amplifier. The power amplifier is set on one side of the U-shaped magnetic yoke corresponding to the winding position of the MIP extraction coil and the MBN extraction coil. The high-frequency signal is amplified by a constant current source composed of the power amplifier to provide excitation for the high-frequency excitation coil to form an alternating magnetic field. The MBN extraction coil receives the signal generated by the magnetic field, amplifies it through an instrument amplifier, and then forms an envelope signal through a power detection chip. The MIP extraction coil signal is modulated and demodulated by a lock-in amplifier to form a MIP signal. The MBN envelope signal and the MIP signal are transmitted to a host computer through an A / D acquisition card for data processing.

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