A detection probe for evaporator heat exchange tubes

Abstract

The application discloses a detection probe for evaporator heat exchange pipes, which comprises a probe shell, an electromagnetic ultrasonic assembly and a lift-off assembly; the electromagnetic ultrasonic assembly is installed in the probe shell; the electromagnetic ultrasonic assembly comprises a first permanent magnet, a second permanent magnet, a third permanent magnet, a transmitting coil and a receiving coil; the polarities of the first permanent magnet, the second permanent magnet and the third permanent magnet on the opposite two sides are the same; the transmitting coil is fixed between the first permanent magnet and the second permanent magnet; the lift-off assembly comprises an upper clamp plate, a lower clamp plate and a driving mechanism; the electromagnetic ultrasonic assembly is installed between the upper clamp plate and the lower clamp plate, and the driving mechanism is in transmission connection with the upper clamp plate and the lower clamp plate, so as to drive the upper clamp plate and the lower clamp plate to move in a direction perpendicular to the probe shell. The magnetic field strength is greatly enhanced, and the effect of enhancing the signal amplitude can be achieved.

Description

Technical Field

[0001] This invention relates to the field of nondestructive testing technology, and in particular to a testing probe for evaporator heat exchange tubes. Background Technology

[0002] The heat exchange tubes of a nuclear power plant's steam generator are typically 10 to 11 meters long and made of stainless steel with ferromagnetic properties. A crucial function of these heat exchange tubes is to cool the nuclear core. To increase the heat exchange area and enhance the cooling effect, and to prevent accidents, corrosion inspections of the heat exchange tubes are required annually.

[0003] Currently, the best solution for detecting pipeline cracks is electromagnetic ultrasonic testing technology in the field of non-destructive testing. In existing solutions that use probes to generate ultrasonic guided waves to detect pipeline cracks, the installation method of the magnet affects the magnetic field strength, which in turn affects the signal amplitude. The traditional method of installing the magnet usually involves installing a coil between the N and S poles of the magnet, which results in poor signal amplitude. In addition, the lift-off distance between the coil and the defect surface of the heat exchanger tube under test is difficult to control.

[0004] No effective solutions have yet been proposed to address the problems in the relevant technologies. Summary of the Invention

[0005] In view of this, it is necessary to provide a detection probe for evaporator heat exchange tubes to solve the technical problems of poor signal amplitude and difficulty in controlling the lift-off distance between the coil and the defective surface of the heat exchange tube under test in the prior art.

[0006] To achieve the above-mentioned technical objectives, the present invention provides a detection probe for evaporator heat exchange tubes, comprising: a probe housing, an electromagnetic ultrasonic component, and a lifting component;

[0007] The electromagnetic ultrasonic component includes a first permanent magnet, a second permanent magnet, a third permanent magnet, a transmitting coil, and a receiving coil. The first, second, and third permanent magnets are arranged side-by-side within the probe housing, and the polarities of the two opposite sides of the first and second permanent magnets, and the polarities of the second and third permanent magnets, are the same. The transmitting coil is fixed between the first and second permanent magnets, and a high-frequency pulse current is loaded in the transmitting coil, enabling it to generate ultrasonic guided waves that propagate along the axial direction of the pipe being tested. The receiving coil is fixed between the second and third permanent magnets and is used to receive the reflected echo signal of the ultrasonic guided waves within the pipe being tested.

[0008] The lifting assembly includes an upper clamping plate, a lower clamping plate, and a driving mechanism; the electromagnetic ultrasound assembly is installed between the upper clamping plate and the lower clamping plate, and the driving mechanism is connected to the upper clamping plate and the lower clamping plate for driving the upper clamping plate and the lower clamping plate to move in a direction perpendicular to the probe housing.

[0009] Furthermore, the turns ratio of the transmitting coil to the receiving coil is 1:2.

[0010] Furthermore, the driving mechanism includes a threaded rod, a first helical gear, a second helical gear, and a transmission component. The two ends of the threaded rod are threadedly connected to the upper clamping plate and the lower clamping plate, respectively. The first helical gear is fixedly connected to the threaded rod, and the first helical gear meshes with the second helical gear. The transmission component is connected to the second helical gear to drive the second helical gear to rotate.

[0011] Furthermore, the probe housing has a cylindrical structure, and one end of the probe housing is recessed downwards to form a concave ring. A cavity is formed inside the concave ring, and the transmission component is placed inside the cavity.

[0012] Furthermore, the transmission component includes a rotating shaft and a roller. One end of the rotating shaft is fixedly connected to the second helical gear, and the other end is fixedly connected to the center of the roller. The upper part of the roller passes through the outer wall of the cavity.

[0013] Furthermore, both the probe housing and the lower clamping plate are provided with openings, which are used to expose the first permanent magnet, the second permanent magnet, the third permanent magnet, the transmitting coil, and the receiving coil.

[0014] Furthermore, both the upper clamping plate and the lower clamping plate are provided with mounting grooves, and the electromagnetic ultrasonic component is snapped together between the two mounting grooves.

[0015] Furthermore, the detection probe also includes a rotary guide, which is mounted on the end of the probe housing for moving or rotating the probe housing in the pipe being detected.

[0016] Furthermore, the rotary guide is fixedly connected to both ends of the probe housing. The rotary guide includes ball bearings and mounting grooves. Several mounting grooves are evenly arranged along the circumference of the rotary guide, and ball bearings are provided in each of the mounting grooves.

[0017] Furthermore, the detection probe also includes a traction assembly, which is fixedly connected to the end face of the rotating guide, and the traction assembly is used to pull the probe housing to move or rotate in the pipe being detected.

[0018] Furthermore, the traction assembly includes a traction tube and a traction rope. The traction tube is fixedly connected to the end face of the rotating guide. One end of the traction rope is fixed inside the traction tube, and the other end is led out from the traction tube.

[0019] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0020] 1. In this invention, the polarities of the two opposite sides of the first permanent magnet and the second permanent magnet, and the second permanent magnet and the third permanent magnet are the same; the transmitting coil is fixed between the first permanent magnet and the second permanent magnet, and the receiving coil is fixed between the second permanent magnet and the third permanent magnet; through the above arrangement, the magnetic field strength is greatly enhanced, which can achieve the effect of enhancing the signal amplitude.

[0021] 2. In this invention, the electromagnetic ultrasonic component is installed between the upper and lower clamping plates, and the driving mechanism is connected to the upper and lower clamping plates for driving the upper and lower clamping plates to move in a direction perpendicular to the probe housing. Through the above arrangement, the lifting distance between the electromagnetic ultrasonic component and the bottom surface of the pipe being inspected can be controlled, thereby improving the signal strength and flaw detection accuracy. Attached Figure Description

[0022] Figure 1 This is a cross-sectional schematic diagram of a detection probe for an evaporator heat exchange tube according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of a detection probe for an evaporator heat exchange tube according to an embodiment of the present invention;

[0024] Figure 3 It is based on the present invention Figure 1 Cross-sectional schematic diagram of the lift-off component;

[0025] In the diagram: 1. Probe housing, 11. Concave ring, 12. Opening, 2. Electromagnetic ultrasound assembly, 21. First permanent magnet, 22. Second permanent magnet, 23. Third permanent magnet, 24. Transmitting coil, 25. Receiving coil, 3. Lifting assembly, 31. Upper clamping plate, 32. Lower clamping plate, 33. Drive mechanism, 331. Threaded rod, 332. First helical gear, 333. Second helical gear, 334. Transmission component, 4. Rotary guide component, 5. Traction assembly, 51. Traction tube, 52. Traction rope. Detailed Implementation

[0026] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0027] like Figure 1-3As shown, the present invention provides a detection probe for evaporator heat exchange tubes, comprising: a probe housing 1, an electromagnetic ultrasonic component 2, and a lifting component 3;

[0028] The electromagnetic ultrasound component 2 is installed inside the probe housing 1;

[0029] The electromagnetic ultrasonic component 2 includes a first permanent magnet 21, a second permanent magnet 22, a third permanent magnet 23, a transmitting coil 24, and a receiving coil 25. The first permanent magnet 21, the second permanent magnet 22, and the third permanent magnet 23 are arranged side by side inside the probe housing 1, and the polarities of the two opposite sides of the first permanent magnet 21 and the second permanent magnet 22, and the second permanent magnet 22 and the third permanent magnet 23 are the same. The transmitting coil 24 is fixed between the first permanent magnet 21 and the second permanent magnet 22, and a high-frequency pulse current is loaded in the transmitting coil 24, which can generate ultrasonic guided waves that propagate along the axial direction of the pipe being tested. The receiving coil 25 is fixed between the second permanent magnet 22 and the third permanent magnet 23, and the receiving coil 25 is used to receive the reflected echo signal of the ultrasonic guided wave inside the pipe being tested.

[0030] The lifting assembly 3 includes an upper clamping plate 31, a lower clamping plate 32, and a driving mechanism 33; the electromagnetic ultrasound assembly 2 is installed between the upper clamping plate 31 and the lower clamping plate 32, and the driving mechanism 33 is connected to the upper clamping plate 31 and the lower clamping plate 32 for driving the upper clamping plate 31 and the lower clamping plate 32 to move in a direction perpendicular to the probe housing 1.

[0031] In this embodiment, the probe housing 1 is inserted into the pipe being tested. By passing a high-frequency pulse current through the transmitting coil 24, an ultrasonic guided wave propagating along the axial direction of the pipe can be formed. Since the polarities of the two opposite sides of the first permanent magnet 21 and the second permanent magnet 22 are the same, and the transmitting coil 24 is connected between the first permanent magnet 21 and the second permanent magnet 22, it can be considered that the magnetic fields generated between the two opposite magnetic poles are in the same direction and are superimposed in the same direction, which can enhance the signal amplitude. The driving mechanism 33 can drive the upper clamping plate 31 and the lower clamping plate 32 to move in a direction perpendicular to the probe housing 1, thereby controlling the lifting distance between the electromagnetic ultrasonic component 2 and the bottom surface of the pipe being tested. This distance is preferably 0.5mm to 2.0mm, which can increase the signal strength and improve the detection accuracy.

[0032] It should be noted that the transmitting coil 24 is made of enameled wire with a diameter of 0.4 mm and wound 40 to 60 turns, preferably 50 turns, and the receiving coil 25 is made of enameled wire with a diameter of 0.2 mm and wound 80 to 120 turns, preferably 100 turns. The signal amplitude is optimal when the ratio of the number of turns of the transmitting coil to the number of turns of the receiving coil is 1:2.

[0033] In addition, both the probe housing 1 and the lower clamping plate 32 are provided with openings 12, which are used to expose the first permanent magnet 21, the second permanent magnet 22, the third permanent magnet 23, the transmitting coil 24 and the receiving coil 25.

[0034] Furthermore, such as Figure 2-3 As shown, the driving mechanism 33 includes a threaded rod 331, a first helical gear 332, a second helical gear 333, and a transmission component 334. The two ends of the threaded rod 331 are threadedly connected to the upper clamping plate 31 and the lower clamping plate 32, respectively. The first helical gear 332 is fixedly connected to the threaded rod 331, and the first helical gear 332 meshes with the second helical gear 333. The transmission component 334 is connected to the second helical gear 333 to drive the second helical gear 333 to rotate. The probe housing 1 has a cylindrical structure. One end of the probe housing 1 has a concave ring 11 formed by downward indentation around its perimeter. A cavity is formed inside the concave ring 11, and the transmission component 334 is placed inside the cavity.

[0035] The transmission component 334 includes a rotating shaft and a roller. One end of the rotating shaft is fixedly connected to the second helical gear 333, and the other end is fixedly connected to the center of the roller. The upper part of the roller passes through the outer wall of the cavity.

[0036] In this embodiment, the structures of the drive mechanism 33 and the probe housing 1 are further defined. The transmission component 334 is placed in the cavity. In use, the roller is simply turned, and the rotation of the roller drives the rotating shaft to rotate, which in turn drives the second helical gear 333 and the first helical gear 332 meshing with it to rotate. Since the center of the first helical gear 332 is fixed with a threaded rod 331, the rotation of the threaded rod 331 causes the upper clamping plate 31 and the lower clamping plate 32 to move along the rod of the threaded rod 331 and toward or away from the opening 12. It should be noted that the part of the roller that passes through the outer wall of the cavity should not be higher than the ring wall of the concave ring 11. The above arrangement can improve the convenience of operation.

[0037] In addition, an elastic element is fixedly connected to the inner wall of the probe housing 1. The elastic element is elastically connected to the upper clamping plate. The elastic element is preferably a spring. With the above arrangement, the spring is always in a compressed state when the upper clamping plate 31 and the lower clamping plate 32 move up and down along the threaded rod 331, so as to improve the stability of the upper clamping plate 31 and the lower clamping plate 32.

[0038] Furthermore, such as Figure 2As shown, the detection probe also includes a rotating guide 4, which is installed at the end of the probe housing 1 to allow the probe housing 1 to move or rotate in the pipe being detected; the rotating guide 4 is fixedly connected to both ends of the probe housing 1, and the rotating guide 4 has several mounting grooves evenly arranged along the circumference, and each of the mounting grooves is provided with a ball bearing.

[0039] In this embodiment, the friction between the probe housing 1 and the pipe being tested is reduced by the rotating guide 4. When a rotational force or forward thrust is provided to the probe housing 1, the ball contacts the pipe wall of the pipe being tested and rolls in the mounting groove, so that the probe housing 1 can move or rotate in the pipe being tested.

[0040] Furthermore, the detection probe also includes a traction component 5, which is fixedly connected to the end face of the rotary guide 4. The traction component 5 is used to pull the probe housing 1 to move or rotate in the pipe being detected. The traction component 5 includes a traction tube 51 and a traction rope 52. The traction tube 51 is fixedly connected to the end face of the rotary guide 4. One end of the traction rope 52 is fixed inside the traction tube 51, and the other end can be led out from the traction tube 51.

[0041] In this embodiment, by providing the traction tube 51, it is convenient to apply rotational force or forward thrust to the probe housing 1. In addition, the traction rope 52 can safely pull the detection probe out of the pipe being detected in the event of an accident. The traction rope 52 is preferably a steel rope.

[0042] The specific workflow of this invention is as follows: First, the lift-off distance between the electromagnetic ultrasonic component 2 and the bottom surface of the pipe being tested is determined. By actuating the rollers, the upper clamping plate 31 and the lower clamping plate 32 move up and down along the threaded rod 331, thereby causing the first permanent magnet 21, the second permanent magnet 22, the third permanent magnet 23, the transmitting coil 24, and the receiving coil 25 to simultaneously move towards or away from the opening 12, thus adjusting the lift-off distance. Next, the traction tube 51 facilitates the application of rotational or forward thrust to the probe housing 1. The rotating guide 4 reduces the friction between the probe housing 1 and the pipe being tested. Finally... During the process of probe housing 1 being inserted into the pipe being tested, a high-frequency pulse current is passed into the transmitting coil 24, which can form an ultrasonic guided wave propagating along the axial direction of the pipe being tested. Since the polarities of the two opposite sides of the first permanent magnet 21 and the second permanent magnet 22 are the same, and the transmitting coil 24 is connected between the first permanent magnet 21 and the second permanent magnet 22, it can be considered that the magnetic field generated between the two magnetic poles of the same name is in the same direction and is superimposed in the same direction, which can achieve the effect of enhancing the signal amplitude. When the ultrasonic guided wave propagates in the pipe being tested, it will generate an echo when it encounters a defect. By detecting the reflected echo signal by the receiving coil 25, the defect information can be obtained.

[0043] The entire workflow is now complete, and anything not described in detail in this specification is existing technology known to those skilled in the art.

[0044] Compared with the prior art, the embodiments of the present invention have at least the following technical effects:

[0045] 1. In this invention, the polarities of the two opposite sides of the first permanent magnet, the second permanent magnet, and the third permanent magnet are the same; the transmitting coil is fixed between the first permanent magnet and the second permanent magnet, and the receiving coil is fixed between the second permanent magnet and the third permanent magnet; through the above arrangement, the magnetic field strength is greatly enhanced, which can achieve the effect of enhancing the signal amplitude.

[0046] 2. In this invention, the electromagnetic ultrasonic component is installed between the upper and lower clamping plates, and the driving mechanism is connected to the upper and lower clamping plates for driving the upper and lower clamping plates to move in a direction perpendicular to the probe housing. Through the above arrangement, the lifting distance between the electromagnetic ultrasonic component and the bottom surface of the pipe being inspected can be controlled, thereby improving the signal strength and flaw detection accuracy.

[0047] 3. The ratio of the number of turns of the transmitting coil to the number of turns of the receiving coil in this invention is 1:2, which can improve the signal amplitude.

[0048] 4. In this invention, the probe housing has a concave ring formed by downward indentation around one end. The upper part of the roller passes through the outer wall of the cavity, and the part of the roller that passes through the outer wall of the cavity does not exceed the ring wall of the concave ring. The above-mentioned arrangement can improve the convenience of operation.

[0049] 5. In this invention, the rotating guide is fixedly connected to both ends of the probe housing. The rotating guide has several mounting grooves evenly arranged along the circumference, and each of the mounting grooves is provided with a ball bearing. Through the above arrangement, the friction between the probe housing and the pipeline being tested can be reduced, making it easier for the probe housing to move or rotate in the pipeline being tested.

[0050] 6. In this invention, an elastic element is fixedly connected to the inner wall of the probe housing. The elastic element is elastically connected to the upper clamping plate. Through the above-mentioned arrangement, the spring is always in a compressed state when the upper and lower clamping plates move up and down along the threaded rod, so as to improve the stability of the upper and lower clamping plates.

[0051] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A detection probe for evaporator heat exchange tubes, characterized in that, include: Probe housing, electromagnetic ultrasound assembly, and lift-off assembly; The electromagnetic ultrasonic component includes a first permanent magnet, a second permanent magnet, a third permanent magnet, a transmitting coil, and a receiving coil. The first, second, and third permanent magnets are arranged side-by-side inside the probe housing, and the polarities of the two opposite sides of the first and second permanent magnets, and the polarities of the second and third permanent magnets, are the same. The transmitting coil is fixed between the first and second permanent magnets, and a high-frequency pulse current is loaded in the transmitting coil, which can generate ultrasonic guided waves that propagate along the axial direction of the pipe being tested. The receiving coil is fixed between the second and third permanent magnets and is used to receive the reflected echo signal of the ultrasonic guided waves in the pipe being tested. The lifting assembly includes an upper clamping plate, a lower clamping plate, and a driving mechanism; the electromagnetic ultrasound assembly is installed between the upper clamping plate and the lower clamping plate, and the driving mechanism is connected to the upper clamping plate and the lower clamping plate for driving the upper clamping plate and the lower clamping plate to move in a direction perpendicular to the probe housing; The driving mechanism includes a threaded rod, a first helical gear, a second helical gear, and a transmission component. The two ends of the threaded rod are threadedly connected to the upper clamping plate and the lower clamping plate, respectively. The first helical gear is fixedly connected to the threaded rod, and the first helical gear meshes with the second helical gear. The transmission component is connected to the second helical gear to drive the second helical gear to rotate. The probe housing is a cylindrical structure. One end of the probe housing is recessed around its perimeter to form a concave ring. A cavity is formed inside the concave ring, and the transmission component is placed inside the cavity. The transmission component includes a rotating shaft and a roller. One end of the rotating shaft is fixedly connected to the second helical gear, and the other end is fixedly connected to the center of the roller. The upper part of the roller passes through the outer wall of the cavity. The detection probe also includes a rotary guide, which is installed at the end of the probe housing to allow the probe housing to move or rotate within the pipe being detected.

2. The detection probe for evaporator heat exchange tubes according to claim 1, characterized in that, The turns ratio of the transmitting coil to the receiving coil is 1:

2.

3. The detection probe for evaporator heat exchange tubes according to claim 1, characterized in that, Both the probe housing and the lower clamping plate are provided with openings, which are used to expose the first permanent magnet, the second permanent magnet, the third permanent magnet, the transmitting coil, and the receiving coil.

4. The detection probe for evaporator heat exchange tubes according to claim 1, characterized in that, The rotary guide is fixedly connected to both ends of the probe housing. The rotary guide includes ball bearings and mounting grooves. Several mounting grooves are evenly arranged along the circumference of the rotary guide, and ball bearings are provided in each of the mounting grooves.

5. The detection probe for evaporator heat exchange tubes according to claim 4, characterized in that, The detection probe also includes a traction assembly, which is installed at the end of the rotary guide to traction the probe housing to move or rotate in the pipe being detected.

6. The detection probe for evaporator heat exchange tubes according to claim 5, characterized in that, The traction assembly includes a traction tube and a traction rope. The traction tube is fixedly connected to the end face of the rotating guide. One end of the traction rope is fixed inside the traction tube, and the other end is led out from the traction tube.

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