Magnetic particle flaw detector for tube plate welding seam

Abstract

The utility model relates to the technical field of magnetic particle flaw detectors, provides a magnetic particle flaw detector for a tube plate welding seam, and aims to solve the problem that the detection efficiency is low due to the fact that two times of crossed detection are needed when an existing magnetic yoke type magnetic detector with two detection feet is used for detecting the tube plate welding seam. The magnetic particle flaw detector comprises: a housing; the control module is arranged on the shell; the three probe foot parts form a triangular area, one probe foot part is used for being in contact with a curved surface of a tube plate welding seam, the other two probe foot parts are used for being in contact with a plane of the tube plate welding seam, each probe foot part is provided with a magnetic pole generating part, and the magnetic pole generating parts are arranged on the shell; the three magnetic pole generating parts are combined to form at least two different magnetic field probe pair groups, and the at least two different magnetic field probe pair groups share one magnetic pole generating part; the magnetic pole generating part in each magnetic field probe pair group is driven by the control module to generate an alternating-current magnetic field, and the magnetic field directions of the alternating-current magnetic fields in the two magnetic field probe pair groups are not parallel.

Description

Technical Field

[0001] This application relates to the technical field of magnetic particle flaw detectors, and more specifically, to a magnetic particle flaw detector for tube-sheet welds. Background Art

[0002] A magnetic particle flaw detector is an instrument used to inspect surface and near-surface defects of steel products. Its flaw detection principle is to utilize the difference in magnetic permeability between surface and near-surface defects (such as cracks, slag inclusions, hairline cracks, etc.) of steel products and the magnetic permeability of steel. After magnetization, the magnetic field at these material discontinuities will be distorted, forming a leakage magnetic field on the surface of the workpiece at the part where the magnetic flux leaks. By using the interaction between the leakage magnetic field at the surface defects of the workpiece and the magnetic powder, the magnetic powder is attracted to form a magnetic powder accumulation at the defect, and under appropriate lighting conditions, the position and shape of the defect are revealed. By observing and interpreting these magnetic powder accumulations, magnetic particle flaw detection is achieved.

[0003] Magnetic particle flaw detection is one of the five conventional methods of non-destructive testing and is also a commonly used means to detect surface or near-surface defects of ferromagnetic materials. Due to its high detection sensitivity, simple and reliable process, it is widely used in the manufacturing, installation, and use processes of pressure vessels (such as boilers, gas storage tanks, oil tanks, etc.), pressure pipelines (such as gas pipelines, oil pipelines, water pipelines), ships, steel, mechanical equipment, aerospace, aviation, electric power, automobiles, motorcycles, petroleum, chemical industry, railways, bridges, elevators, amusement parks, etc.

[0004] Among them, when a pipe fitting is welded to a flat plate, a tube-sheet weld is formed. Tube-sheet welds are common welds. Currently, there is no dedicated magnetic particle flaw detector for tube-sheet welds. Generally, a yoke-type magnetic particle flaw detector with two probe feet is used to detect surface defects of tube-sheet welds. However, the yoke-type magnetic flaw detector with two probe feet needs to perform cross-detection twice at one position (because when the magnetic field direction is perpendicular to the defect extension direction, the leakage magnetic field at the defect is the largest and the detection sensitivity is the highest; when the magnetic field direction is parallel to the defect extension direction, no magnetic trace display is generated and the defect cannot be detected, so the yoke-type magnetic flaw detector with two probe feet needs to perform cross-detection twice), and there needs to be an overlap area at each detection position, otherwise there will be undetected cases, so the detection efficiency of the yoke-type magnetic flaw detector with two probe feet is low.

[0005] Therefore, the existing technology still needs to be improved. Summary of the Utility Model

[0006] The purpose of this application is to provide a magnetic particle flaw detector for tube-sheet welds to solve the problem of low detection efficiency when the existing yoke-type magnetic flaw detector with two probe feet needs to perform cross-detection twice when detecting tube-sheet welds.

[0007] To achieve the above objective, the technical solution adopted in the embodiment of this application is:

[0008] A magnetic particle flaw detector for tube-sheet welds, comprising:

[0009] Housing;

[0010] A control module, which is arranged on the housing;

[0011] Three probe feet parts, which form a triangular area, one of which is used to contact the curved surface of the tube sheet weld, and the other two are both used to contact the flat surface of the tube sheet weld. Each of the probe feet parts has a magnetic pole generating part, and the magnetic pole generating part is arranged on the housing;

[0012] After the three magnetic pole generating parts are combined, at least two different magnetic field probe pairs are formed, and at least two different magnetic field probe pairs share one magnetic pole generating part;

[0013] The magnetic pole generating parts in each magnetic field probe pair generate an alternating magnetic field through the drive of the control module, and the magnetic field directions of the alternating magnetic fields in the two magnetic field probe pairs are not parallel.

[0014] According to the magnetic particle flaw detector for tube sheet welds described above, after the three magnetic pole generating parts are combined, three different magnetic field probe pairs are formed, and the magnetic field directions of the alternating magnetic fields in the three magnetic field probe pairs are not parallel;

[0015] Among them, the alternating magnetic fields generated by the three magnetic pole generating parts through the drive of the control module include a first alternating magnetic field, a second alternating magnetic field and a third alternating magnetic field, and the first alternating magnetic field, the second alternating magnetic field and the third alternating magnetic field jointly cover the tube sheet weld area covered by the paths of the three probe feet parts.

[0016] According to the magnetic particle flaw detector for tube sheet welds described above, the triangular area is an isosceles triangular area;

[0017] Among them, the magnetic pole generating part includes an iron core and a coil, the iron core is arranged on the housing, and the coil is arranged on the iron core.

[0018] According to the magnetic particle flaw detector for tube sheet welds described above, the end of the probe foot part close to the tube sheet weld is set as a semi-circular end.

[0019] According to the magnetic particle flaw detector for tube sheet welds described above, the iron cores of the three probe feet parts are connected to each other;

[0020] Among them, the iron cores of the three probe feet parts are connected by an L-shaped iron core and a U-shaped iron core. The L-shaped iron core is connected to the middle of the U-shaped iron core. The semi-circular end corresponding to the L-shaped iron core is used to adapt to the curved surface of the tube sheet weld, and the two semi-circular ends corresponding to the U-shaped iron core are used to adapt to the flat surface of the tube sheet weld.

[0021] According to the magnetic particle flaw detector for tube sheet welds described above, the magnetic particle flaw detector further includes:

[0022] Three pulley assemblies, which are respectively hingedly arranged on the corresponding semi-circular ends.

[0023] According to the magnetic particle flaw detector for tube sheet welds described above, the pulley assembly includes:

[0024] A hinge shaft, which is rotatably arranged at the center of the corresponding semi-circular end;

[0025] A pulley seat, which is connected to the semi-circular end through the hinge shaft;

[0026] Two pulleys, which are respectively rotatably arranged at both ends of the pulley seat and penetrate through the pulley seat;

[0027] The bottom end of the pulley is lower than the bottom end of the semi-circular end.

[0028] According to the magnetic particle flaw detector for tube sheet welds described above, the control module includes:

[0029] A main unit, which is arranged in the housing, and the coil of the probe part is electrically connected to the main unit;

[0030] A start switch, which is arranged on the housing and is electrically connected to the main unit.

[0031] According to the magnetic particle flaw detector for tube sheet welds described above, the magnetic particle flaw detector further includes:

[0032] A black and white light lamp module, which is arranged on one side of the housing close to the probe part and is located between the three probe parts, and the black and white light lamp module is electrically connected to the control module.

[0033] According to the magnetic particle flaw detector for tube sheet welds described above, the magnetic particle flaw detector further includes:

[0034] A power supply module, which is arranged in the housing, and the power supply module is electrically connected to the control module and is used to supply power to the control module.

[0035] The beneficial effects of a magnetic particle flaw detector for tube sheet welds provided by this application are at least as follows:

[0036] It can be foreseen that the overlapping area exists for the alternating magnetic fields with non-parallel magnetic field directions generated by the magnetic pole generating parts in the two magnetic field probe pairs through the drive of the control module, so that this application can detect the tube sheet weld area covered by the paths of the three probe parts without cross detection, and the detection efficiency is high. Description of the Drawings

[0037] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required for use in the embodiments or the description of the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0038] Figure 1 It is a schematic structural diagram of a tube-sheet weld formed by connecting a tube and a plate in a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application.

[0039] Figure 2 It is a schematic application structural diagram of a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application without a pulley assembly.

[0040] Figure 3 It is a schematic plan view of a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application without a pulley assembly.

[0041] Figure 4 It is a schematic application structural diagram of a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application with a pulley assembly.

[0042] Figure 5 It is a schematic three-dimensional structure diagram of a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application with a pulley assembly.

[0043] Figure 6 It is a schematic plan view of a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application with a pulley assembly.

[0044] Figure 7 It is a schematic structural diagram of the detection foot part in a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application.

[0045] Figure 8 It is a schematic front view structure diagram of the connection between the respective iron cores in the three detection foot parts in a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application.

[0046] Figure 9 It is a schematic side view structure diagram of the connection between the respective iron cores in the three detection foot parts in a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application.

[0047] Figure 10 It is an equivalent electrical diagram formed by the three detection foot parts in a magnetic particle flaw detector for tube-sheet welds provided in an embodiment of the present application.

[0048] Figure 11Schematic diagram of three groups of composite alternating magnetic fields generated by three detection feet in a magnetic particle flaw detector for tube sheet welds provided in an embodiment of the present application.

[0049] Figure 12 Schematic diagram of the detection of a group of composite alternating magnetic fields in a magnetic particle flaw detector for tube sheet welds provided in an embodiment of the present application.

[0050] Among them, each reference numeral in the figure:

[0051] 1. Outer shell; 11. Main machine installation shell; 12. Power supply installation shell; 2. Control module; 21. Main machine; 22. Start switch; 3. Detection foot; 31. Iron core; 311. L-shaped iron core; 312. U-shaped iron core; 32. Coil; 33. Semi-circular end; 41. Tube sheet weld; 42. Curved surface; 43. Flat surface; 5. Black and white light lamp module; 6. Pulley assembly; 61. Hinge shaft; 62. Pulley seat; 63. Pulley; 7. Power supply module. Detailed implementation manners

[0052] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer and more understandable, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0053] It should be noted that when a component is referred to as "fixed to" or "disposed on" another component, it can be directly or indirectly located on that another component. When a component is referred to as "connected to" another component, it can be directly or indirectly connected to that another component. The orientations or positions indicated by the terms "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientations or positions shown in the drawings, and are only for convenience of description and cannot be construed as limitations to the technical solution of the present application. The terms "first" and "second" are only used for the purpose of convenient description and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of technical features. The meaning of "a plurality" is two or more unless otherwise specifically defined.

[0054] A magnetic particle flaw detector is an instrument used to inspect surface and near-surface defects of steel products. Its flaw detection principle is to utilize the difference in magnetic permeability between surface and near-surface defects (such as cracks, slag inclusions, hair cracks, etc.) of steel products and the magnetic permeability of steel. After magnetization, the magnetic fields at these material discontinuities will be distorted, forming a leakage magnetic field on the surface of the workpiece at the partial magnetic flux leakage points. By using the interaction between the leakage magnetic field at the surface defects of the workpiece and the magnetic powder, the magnetic powder is attracted to form a magnetic powder accumulation at the defects. Under appropriate lighting conditions, the position and shape of the defects are revealed. By observing and interpreting the accumulation of these magnetic powders, magnetic particle flaw detection is achieved.

[0055] Magnetic particle testing is one of the five conventional non-destructive testing methods and is also a commonly used means to detect surface or near-surface defects in ferromagnetic materials. Due to its high detection sensitivity and simple and reliable process, it is widely used in the manufacturing, installation, and use processes of pressure vessels (such as boilers, gas storage tanks, oil tanks, etc.), pressure pipelines (gas pipelines, oil pipelines, water pipelines), ships, steel, mechanical equipment, aerospace, aviation, electric power, automobiles, motorcycles, petroleum, chemical industry, railways, bridges, elevators, amusement parks, etc.

[0056] Among them, when a pipe fitting is welded to a flat plate, a tube sheet weld is formed. Tube sheet welds are common welds. Currently, there is no dedicated magnetic particle testing instrument for tube sheet welds. The four-probe magnetic particle testing instrument is difficult to adapt to two detection surfaces with different curvatures and is obviously not applicable to the defect detection of tube sheet welds. Currently, generally, a two-probe yoke-type magnetic particle testing instrument is used to detect surface defects of tube sheet welds. However, the two-probe yoke-type magnetic detector needs to perform cross detection twice at one position (because when the magnetic field direction is perpendicular to the defect extension direction, the leakage magnetic field at the defect is the largest and the detection sensitivity is the highest; when the magnetic field direction is parallel to the defect extension direction, no magnetic trace display is generated and the defect cannot be detected. Therefore, the two-probe yoke-type magnetic detector needs to perform cross detection twice), and there needs to be an overlapping area at each detection position, otherwise there will be undetected cases. Therefore, the detection efficiency of the two-probe yoke-type magnetic detector is low.

[0057] For this reason, referring to Figure 1 、 Figure 2 、 Figure 3 and Figure 7 ,an embodiment of the present application provides a magnetic particle testing machine for tube sheet welds, including a housing 1, a control module 2, and three probe parts 3. The control module 2 is arranged on the housing 1. The three probe parts 3 form a triangular area, and the triangular area is preferably set as an isosceles triangular area. Among them, one is used to contact the curved surface 42 of the tube sheet weld 41, and the other two are both used to contact the flat surface 43 of the tube sheet weld 41. Among them, each probe part 3 has a magnetic pole generating part, and the magnetic pole generating part is arranged on the housing 1. After the three magnetic pole generating parts are combined, at least two different magnetic field probe pairs are formed. At least two different magnetic field probe pairs share one magnetic pole generating part. The magnetic pole generating parts in each magnetic field probe pair generate an alternating magnetic field through the drive of the control module 2, and the magnetic field directions of the alternating magnetic fields in the two magnetic field probe pairs are not parallel.

[0058] It can be foreseen that the alternating magnetic fields with non-parallel magnetic field directions generated by the magnetic pole generating parts in the two magnetic field probe pairs through the drive of the control module have an overlapping area, so that in this embodiment, it is not necessary to perform cross detection, and the tube sheet weld 41 area covered by the three probe parts 3 can be detected, and the detection efficiency is high.

[0059] Optionally, refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 7 , in one embodiment, after combining the three magnetic pole generating parts, three different magnetic field probe pair groups are formed. The magnetic field directions of the alternating magnetic fields in the three magnetic field probe pair groups are not parallel. Among them, the alternating magnetic fields generated by driving the three magnetic pole generating parts through the control module 2 include a first alternating magnetic field, a second alternating magnetic field, and a third alternating magnetic field. The first alternating magnetic field, the second alternating magnetic field, and the third alternating magnetic field jointly cover the tube sheet weld area covered by the paths of the three probe parts. The magnetic pole generating part includes an iron core 31 and a coil 32. The iron core 31 is arranged on the lower end surface of the housing 1, and the coil 32 is arranged on the iron core 31.

[0060] It can be foreseen that, compared with the two alternating magnetic fields generated by forming two different magnetic field probe pair groups, the three different magnetic field probe pair groups formed in this embodiment can generate three alternating magnetic fields, having a larger detection coverage range, thereby further improving the detection efficiency of the magnetic particle flaw detector in this embodiment.

[0061] Among them, refer to Figure 10 , the equivalent electrical diagram formed by the three probe parts 3 is as follows. For the convenience of description, the three probe parts 3 are respectively named probe part A, probe part B, and probe part C, and the coils 32 of the three probe parts 3 are respectively named coil A, coil B, and coil C.

[0062] It can be seen from the figure that the equivalent electrical diagram has a center point O. The coil A, the coil B, and the coil C are connected to the point O. That is to say, the coil A, the coil B, and the coil C are connected to each other in pairs. In order for the three probe parts 3 to generate three groups of composite alternating magnetic fields through the drive of the control module 2, the control module 2 applies the following currents to each coil 32 (probe part A, probe part B, and probe part C). Refer to the following table:

[0063]

[0064]

[0065] Among them, within time T, by controlling module 2 to conduct coil A and coil B, a magnetic field direction with a current direction from probe foot A to probe foot B can be generated; within time T to 2T, by controlling module 2 to conduct coil B and coil C, a magnetic field direction with a current direction from probe foot B to probe foot C can be generated; within time 2T to 3T, by controlling module 2 to conduct coil C and coil A, a magnetic field direction with a current direction from probe foot C to probe foot A can be generated; within time 3T to 4T, by controlling module 2 to conduct coil B and coil A, a magnetic field direction with a current direction from probe foot B to probe foot A can be generated; within time 4T to 5T, by controlling module 2 to conduct coil A and coil C, a magnetic field direction with a current direction from probe foot A to probe foot C can be generated; within time 5T to 6T, by controlling module 2 to conduct coil C and coil B, a magnetic field direction with a current direction from probe foot C to probe foot B can be generated.

[0066] Refer to Figure 11 , the magnetic field direction with a current direction from probe foot A to probe foot B and the magnetic field direction with a current direction from probe foot B to probe foot A are both for generating the direction of the first alternating magnetic field AB; the magnetic field direction with a current direction from probe foot B to probe foot C and the magnetic field direction with a current direction from probe foot C to probe foot B are both for generating the direction of the second alternating magnetic field BC; the magnetic field direction with a current direction from probe foot C to probe foot A and the magnetic field direction with a current direction from probe foot A to probe foot C are both for generating the direction of the third alternating magnetic field AC. That is to say, the three groups of composite alternating magnetic fields include the first alternating magnetic field, the second alternating magnetic field, and the third alternating magnetic field. The first alternating magnetic field, the second alternating magnetic field, and the third alternating magnetic field are formed alternately over time and jointly cover the area of the tube sheet weld 41 covered by the three probe feet 3.

[0067] Among them, the center point O is located in the middle of the three composite alternating magnetic fields. Through the radiation effect of the point-to-point magnetic field, the three alternating magnetic fields act on the area of the tube sheet weld 41 in a combined manner, that is, a uniform composite magnetic field is generated in the area of the center point O of the magnetic particle flaw detector, realizing the detection of various defects in the area of the tube sheet weld 41 at the same time. Refer to Figure 12 .

[0068] Optionally, refer to Figure 3 , Figure 5 and Figure 6 , in an embodiment, the housing 1 includes a main machine mounting shell 11 and a power supply mounting shell 12. The power supply mounting shell 12 is arranged on the main machine mounting shell 11, and the three probe feet 3 are arranged on the side of the main machine mounting shell 11 away from the power supply mounting shell 12.

[0069] Optionally, refer to Figure 1 and Figure 2, in one embodiment, the outer shape of the power supply mounting case 12 is set as a handle mounting case to facilitate the operator to hold by hand.

[0070] Optionally, refer to Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 , in one embodiment, the control module 2 includes a host 21 and a start switch 22. The host 21 is disposed in the host mounting case 11. The coil 32 of the probe part 3 passes through the host mounting case 11 and is electrically connected to the host 21. The start switch 22 is disposed on the outer shell 1, specifically, it can be disposed on the inner side of the power supply mounting case 12 close to the host mounting case 11. The start switch 22 is electrically connected to the host 21.

[0071] Optionally, refer to Figure 3 , in one embodiment, the magnetic particle flaw detector further includes a black and white light lamp module 5, which is disposed on one side of the host mounting case 11 close to the probe part 3 and is located between the three probe parts 3. The black and white light lamp module 5 is electrically connected to the host 21. Among them, the black and white light lamp module 5 internally integrates a black light lamp (ultraviolet lamp) and a white light lamp.

[0072] Optionally, refer to Figure 3 , in one embodiment, the magnetic particle flaw detector further includes a power supply module 7. The power supply module 7 is disposed in the power supply mounting case 12. The output end of the power supply module 7 is electrically connected to the input end of the host 21 and is used to supply power to the host 21.

[0073] Optionally, in one embodiment, the power supply module 7 can be set as a battery module. The battery module internally integrates a battery and its protection circuit. Among them, the battery module can be installed on the host 21 through a quick connection structural member, and a fully charged battery module can be replaced at any time to achieve the purpose of long battery life of the whole machine.

[0074] Optionally, refer to Figure 1 , Figure 2 and Figure 3 , in one embodiment, one end of the probe part 3 close to the tube sheet weld 41 is set as a semi-circular end 33. In this embodiment, by setting one end of the probe part 3 close to the tube sheet weld 41 as the semi-circular end 33, the probe part 3 can be adapted to the curved surface 42 or the plane 43 of the tube sheet weld 41.

[0075] Optionally, refer to Figure 7 , Figure 8 and Figure 9 , in one embodiment, the iron cores 31 of the three probe parts 3 are connected to each other.

[0076] Among them, the iron cores 31 of the three detection feet 3 can be connected by an L-shaped iron core 311 and a U-shaped iron core 312. The L-shaped iron core 311 is connected to the middle of the U-shaped iron core 312. At this time, the semicircular end 33 corresponding to the L-shaped iron core 311 can adapt to the curved surface 42 of the tube sheet weld 41, and the two semicircular ends 33 corresponding to the U-shaped iron core 312 can adapt to the plane 43 of the tube sheet weld 41.

[0077] The connection between the L-shaped iron core 311 and the U-shaped iron core 312 can be a welded connection or a rigid fixation in other ways.

[0078] Optionally, refer to Figure 4 、 Figure 5 and Figure 6 , in an embodiment, the magnetic particle flaw detector further includes three pulley assemblies 6. The three pulley assemblies 6 are hinged on the corresponding semicircular ends 33. By setting the pulley assemblies 6 in this embodiment, the detection efficiency of the magnetic particle flaw detector can be improved.

[0079] Optionally, refer to Figure 4 、 Figure 5 and Figure 6 , in an embodiment, the pulley assembly 6 includes a hinge shaft 61, a pulley seat 62 and two pulleys 63. The hinge shaft 61 is rotatably arranged at the center of the corresponding semicircular end 33. The pulley seat 62 is connected to the semicircular end 33 (detection foot 3) through the hinge shaft 61. The two pulleys 63 are respectively rotatably arranged at both ends of the pulley seat 62 and pass through the pulley seat 62. The bottom end of the pulley 63 is lower than the bottom end of the semicircular end 33 for driving the detection foot 3 to move.

[0080] It should be noted that when the detection foot 3 moves on the curved surface 42 or the plane 43 of the tube sheet weld 41 through the pulley assembly 6, the detection foot end of the detection foot 3 and the curved surface 42 or the plane 43 of the tube sheet weld 41 are restricted within a certain range.

[0081] The working principle of a magnetic particle flaw detector for tube sheet welds is as follows: The main machine 21 serves as the control circuit of the entire magnetic particle flaw detector. It converts the power module 7 into three-way composite alternating current to drive the coils 32 of the three detection feet 3 to work. Under the drive of the three-way composite alternating current, three groups of composite alternating magnetic fields are generated. The coils 32 are wound around the iron cores 31, and the three groups of composite alternating magnetic fields are transmitted to the area of the tube sheet weld 41 to be detected through the iron cores 31, and three corresponding groups of composite alternating magnetic fields are formed in this area, and the tube sheet weld 41 is detected in cooperation with magnetic powder and the magnetic particle flaw detector.

[0082] Among them, the operation steps of the magnetic particle flaw detector in this embodiment can specifically be as follows: First, press the start switch 22 for more than 0.5 s, and the power module 7 is connected to the host 21. Among them, the start switch 22 has three functions, namely, connecting the power module 7, magnetizing work, and switching between the black light and the white light;

[0083] Press and hold the start switch 22. At this time, the host 21 works, and the iron core 31 and the coil 32 of the detection foot 3 are magnetized. At the same time, the black light or the white light automatically lights up (when performing ordinary black magnetic particle detection, the white light should be used; when performing fluorescent magnetic particle detection, the black light should be used). The magnetic particle flaw detector can be pushed to perform flaw detection operations. When the flaw detection operation is completed, the magnetic particle flaw detector can be stopped by releasing the start switch 22. The switching between the black light and the white light can be achieved by pressing the start switch 22 five times continuously within 2 s. In order to achieve the purpose of power saving and safe electricity use, the magnetic particle flaw detector in this embodiment can automatically switch the power supply of the power module 7 through the host 21 after being stationary for more than a certain period of time.

[0084] In summary, a magnetic particle flaw detector for a tube sheet weld provided by this application includes a housing 1, a control module 2, and three detection feet 3. The control module 2 is arranged on the housing 1. The three detection feet 3 form a triangular area. Among them, one is used to contact the curved surface 42 of the tube sheet weld 41, and the other two are both used to contact the flat surface 43 of the tube sheet weld 41. Among them, each detection foot 3 has a magnetic pole generating part. The magnetic pole generating part is arranged on the housing 1. After the three magnetic pole generating parts are combined, at least two different magnetic field detection foot pairs are formed. At least two different magnetic field detection foot pairs share one magnetic pole generating part. The magnetic pole generating part in each magnetic field detection foot pair generates an alternating magnetic field through the drive of the control module 2. The magnetic field directions of the alternating magnetic fields in the two magnetic field detection foot pairs are not parallel. It can be foreseen that the two alternating magnetic fields with non-parallel magnetic field directions generated by the magnetic pole generating parts in the two magnetic field detection foot pairs have an overlapping area, so that this application can detect the tube sheet weld 41 area covered by the paths of the three detection feet 3 without cross detection, and the detection efficiency is high.

[0085] The above are only the preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

1. A magnetic particle flaw detector for tube sheet welds, characterized in that, Comprising: A housing; A control module, which is arranged on the housing; Three probe feet parts, which form a triangular area, one of which is used to contact the curved surface of the tube sheet weld seam, and the remaining two are both used to contact the flat surface of the tube sheet weld seam. Each of the probe feet parts has a magnetic pole generating part, and the magnetic pole generating part is arranged on the housing; After the combination of the three magnetic pole generating parts, at least two different magnetic field probe pair groups are formed, and at least two different magnetic field probe pair groups share one of the magnetic pole generating parts; The magnetic pole generating parts in each of the magnetic field probe pair groups generate an alternating magnetic field through the drive of the control module, and the magnetic field directions of the alternating magnetic fields in the two magnetic field probe pair groups are not parallel.

2. The magnetic particle flaw detector for tube sheet welds according to claim 1, characterized in that, After the combination of the three magnetic pole generating parts, three different magnetic field probe pair groups are formed, and the magnetic field directions of the alternating magnetic fields in the three magnetic field probe pair groups are not parallel; Among them, the alternating magnetic fields generated by the drive of the control module by the three magnetic pole generating parts include a first alternating magnetic field, a second alternating magnetic field and a third alternating magnetic field, and the first alternating magnetic field, the second alternating magnetic field and the third alternating magnetic field jointly cover the tube sheet weld seam area covered by the paths of the three probe feet parts.

3. The magnetic particle flaw detector for tube sheet welds as described in claim 1, characterized in that, The triangular area is an isosceles triangular area; Among them, the magnetic pole generating part includes an iron core and a coil, the iron core is arranged on the housing, and the coil is arranged on the iron core.

4. The magnetic particle flaw detector for tube sheet welds according to claim 1, characterized in that One end of the probe feet part close to the tube sheet weld seam is set as a semi-circular end.

5. The magnetic particle flaw detector for tube sheet welds according to claim 4, characterized in that, The iron cores of the three probe feet parts are connected to each other; Among them, the iron cores of the three probe feet parts are connected by an L-shaped iron core and a U-shaped iron core. The L-shaped iron core is connected to the middle of the U-shaped iron core. The semi-circular end corresponding to the L-shaped iron core is used to adapt to the curved surface of the tube sheet weld seam, and the two semi-circular ends corresponding to the U-shaped iron core are used to adapt to the flat surface of the tube sheet weld seam.

6. The magnetic particle flaw detector for tube sheet welds according to claim 4, characterized in that, The magnetic particle flaw detector further includes: Three pulley assemblies, which are respectively hinged on the corresponding semi-circular ends.

7. The magnetic particle flaw detector for tube sheet welds according to claim 6, characterized in that, The pulley assembly includes: A hinge shaft, which is rotatably arranged at the center of the corresponding semi-circular end; A pulley seat, which is connected to the semi-circular end through the hinge shaft; Two pulleys, which are respectively rotatably arranged at both ends of the pulley seat and penetrate through the pulley seat; The bottom end of the pulley is lower than the bottom end of the semi-circular end.

8. The magnetic particle flaw detector for tube sheet welds according to claim 1, characterized in that, The control module includes: A main machine, the main machine is arranged in the housing, and the coil of the probe feet part is electrically connected to the main machine; A start switch, which is arranged on the housing and is electrically connected to the main machine.

9. The magnetic particle flaw detector for tube sheet welds according to claim 1, wherein The magnetic particle flaw detector further includes: A black and white light lamp module, which is arranged on one side of the housing close to the probe feet part and is located between the three probe feet parts, and the black and white light lamp module is electrically connected to the control module.

10. The magnetic particle flaw detector for tube sheet welds according to claim 1, characterized in that, The magnetic particle flaw detector further includes: A power supply module, which is arranged in the housing, the power supply module is electrically connected to the control module and is used to supply power to the control module.

Images