CN210221906U - Horizontal shear wave transducer for detecting coarse-grained material welding seam - Google Patents
Horizontal shear wave transducer for detecting coarse-grained material welding seam Download PDFInfo
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- CN210221906U CN210221906U CN201920773858.XU CN201920773858U CN210221906U CN 210221906 U CN210221906 U CN 210221906U CN 201920773858 U CN201920773858 U CN 201920773858U CN 210221906 U CN210221906 U CN 210221906U
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Abstract
The utility model relates to a horizontal shear wave transducer for detecting coarse-grained material welding seams, which comprises a transducer body, a shell for packaging the transducer body, a wedge block for bearing the transducer body and a sound absorption layer connected with the end part of the wedge block; the wedge block is adopted to transmit horizontal shear waves into a welding line at a certain angle, and the sound absorption layer is adopted to eliminate redundant sound waves in the wedge block. Compared with the prior art, the utility model has the advantages of simple structure, the testing result is accurate, convenient to use, be convenient for install.
Description
Technical Field
The utility model relates to a guided wave transducer especially relates to a horizontal shear wave transducer that is used for coarse grain material welding seam to detect.
Background
The shear horizontal wave is a transverse wave in which the direction of particle vibration is parallel to the surface of the workpiece. When the traditional ultrasonic is used for detecting a coarse-grained material welding seam, the propagation direction of sound waves can be changed and a large number of clutter signals are generated due to the fact that the grains of the welding seam are large. The horizontal shear wave is slightly influenced by the coarse-grained material due to the fact that the vibration direction is different from the transverse wave, and the horizontal shear wave is an ideal coarse-grained material welding line detection waveform.
Chinese patent CN 106093209A discloses a magnetostrictive phased array horizontal shearing guided wave transducer, wherein a plurality of magnetostrictive thin sheet array elements are composed of respective magnetostrictive thin sheets, direct current bias coils and alternating current coils, the two coils are orthogonally wound on the magnetostrictive thin sheets, and coil ends of the array elements are connected with a main interface through respective interfaces; the alternating current coil can be connected with the power amplifying circuit module through the line switching device; or the signal conditioning method circuit module can be connected with the signal conditioning method circuit module through the line switching device; the alternating current coil is used as a detection coil, the direct current bias coil provides a direct current bias magnetic field, and the plurality of magnetostrictive thin sheet array elements form a one-dimensional linear array. The patent technology provides a magnetostrictive phased array SH (horizontal shear) guided wave transducer, and can realize accurate control and comprehensive scanning of an SH guided wave mode. However, the above-mentioned patent techniques and the common magnetostrictive excited horizontal shear wave are not obliquely incident, and cannot detect the weld.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a level shear wave transducer for coarse grain material welding seam detects in order to overcome the defect that above-mentioned prior art exists, the utility model discloses a transducer can realize the oblique incidence of level shear wave to the realization is to the detection of coarse grain material welding seam.
The purpose of the utility model can be realized through the following technical scheme:
a horizontal shear wave transducer for detecting a coarse-grained material welding seam comprises a transducer body, a shell used for packaging the transducer body, a wedge used for bearing the transducer body and a sound absorption layer connected to the end of the wedge.
The utility model discloses a have certain inclination's voussoir, with the horizontal shear wave that the transducer body produced in order certain angular propagation entering welding seam to set up unnecessary sound wave in the voussoir is eliminated to the tip at the voussoir, thereby realize changing the incident direction of horizontal shear wave and realize the accurate detection to coarse grain material welding seam.
The wedge block is made of organic glass or carbon steel; the inclined plane of voussoir and the contained angle between the ground be 27 ~ 70.
The acoustic impedance of the organic glass is 3.2 × 103MPa/s, the acoustic transmission performance is excellent, and the organic glass can be matched with the acoustic impedance of detected objects made of different materials. When steel welding seams are detected, carbon steel is recommended to be used as wedge blocks, and organic glass is recommended to be used when non-metal materials are detected. Because the material is the same as or similar to the detected material, the sound energy loss is minimum. The oblique incidence of the horizontal shear wave can be achieved by the action of the wedge, which is preferably at an angle of 27 ° to 70 °. When the angle of the wedge block is 27-45 degrees, the defects on the surface of the vertical welding seam can be mainly found by detecting the sound waves, such as incomplete penetration of the root of the welding seam; when the wedge angle is 45-70 degrees, the wedge angle is mainly used for discovering defects of the center and the near surface of a welding seam, such as non-fusion between layers, near surface cracks and the like. When the wedge angle is less than 27 °, the sound wave is close to normal incidence, the oblique incidence component in the sound wave is small, and it is difficult to find defects in the weld. When the wedge angle is greater than 70 deg., most of the acoustic energy in the transducer cannot be tilted into the weld being tested due to the near horizontal direction of propagation of the acoustic wave. This range is therefore the optimum angle for detecting defects in the weld.
The contact surfaces of the sound absorption layer and the wedge block are rectangular teeth matched with each other; the material is sound-absorbing material.
Reflected waves and projected waves are generated when reflected waves from the interface of the workpiece and the wedge propagate to the acoustic absorption layer. When the sound absorption layer is in a sawtooth shape, the contact area of sound waves of the sound absorption layer is increased to the greatest extent, most of the sound waves can be absorbed by the sound absorption layer, and a small part of the sound waves form reflected waves. Due to the action of the sawtooth-shaped reflecting surface, the original propagation direction of the reflected wave is changed into a scattered wave, and the interference sound wave generated when the sound wave enters a workpiece or is received by the transducer is further reduced.
The transducer body is including arranging in permanent magnet on the inclined plane of voussoir, arranging in inside magnetic induction coil of permanent magnet, laminate in the magnetic induction thin slice of magnetic induction coil lower surface, laminate in the epoxy coupling layer of magnetic induction thin slice lower surface, and with the signal line joint that magnetic induction coil connects.
Wherein, the effect of each part is: the permanent magnet is used for generating a horizontal bias magnetic field; the magnetic induction coil is used for generating an eddy current and a variable magnetic field, and receiving and exciting a horizontal shear wave signal; the magnetic induction sheet generates magnetostrictive vibration under the action of the permanent magnet and the magnetic induction coil to excite horizontal shear waves; the signal wire joint is used for transmitting magnetic induction coil signals; the epoxy resin coupling layer is used for enabling the magnetic induction thin sheet and the wedge block to achieve impedance matching and transmitting horizontal shear waves into the wedge block.
The permanent magnet is a U-shaped magnet, and the permanent magnet is made of neodymium iron boron.
The magnetic induction coil is a reverse-folded annular copper coil, and the number of turns of the magnetic induction coil is 20-100 turns, preferably 40 turns.
The number of interface pins of the signal wire connector is matched with the number of turns of the magnetic induction coil, and is preferably 40. The length direction of the magnetic induction sheet is in contact connection with the N pole and the S pole of the permanent magnet respectively;
the width of the magnetic induction sheet is 25-75 mm, preferably 50 mm;
the thickness of the magnetic induction sheet is 0.1-0.3 mm, and preferably 0.25 mm;
the magnetic induction sheet is made of iron-cobalt alloy or nickel with the purity of 99.99%.
The epoxy resin coupling layer is prepared from epoxy resin quick-drying glue.
The shell is made of a non-wave-conducting material and is fixed on the inclined plane of the wedge block through a bolt.
The utility model discloses a use method does:
the utility model discloses a horizontal shear wave transducer is for detecting the probe of coarse grain material welding seam, and the horizontal shear wave of production has a plurality of incident angles, can realize the horizontal shear wave oblique incidence of different angles according to the difference of voussoir angle. When examining measuring, adopt coarse grain material to carry out the probe test to the test block, the utility model discloses a on the material that awaits measuring is arranged in to the bottom surface of voussoir, probe excitation horizontal shear wave passes in the middle of the welding seam detects the welding seam and the horizontal through-hole of opposite side, detects 6 horizontal through-holes respectively to record each horizontal through-hole sound journey. And comparing the detection result with the theoretical sound wave propagation sound path, and displaying that the measured sound path is consistent with the theoretical sound path, thereby indicating that the excited horizontal shear wave is not influenced by coarse grains in the welding seam to deflect. Therefore, the probe can be used for detecting the coarse-grained material weld joint, and the detection method is consistent with that of a conventional oblique probe, namely, the probe is perpendicular to the weld joint to perform sawtooth scanning.
Compared with the prior art, the utility model has the advantages of it is following:
(1) the horizontal shear wave is adopted to detect the welding seam, and compared with the traditional ultrasonic detection, the detection precision is higher and the result is more accurate;
(2) the horizontal shear wave can not be influenced by coarse grains in the detected welding seam to change the propagation direction, so that the defect positioning is more accurate, and the detection of the welding seam of coarse grain materials such as austenitic stainless steel can be realized.
(3) The attenuation of horizontal shear waves in the material is smaller than that of longitudinal waves and transverse waves, so that non-metallic materials with larger acoustic attenuation, such as PE material welding seams, can be detected.
(4) The magnetic induction sheet for generating the horizontal shear wave in the transducer is made of a metal material, and compared with the material of a traditional piezoelectric wafer, the magnetic induction sheet can bear the maximum 300V and the maximum 40A electric signals and generate the horizontal shear wave with stronger energy.
(5) The incidence direction of the horizontal shear wave is changed by adopting the wedge block, so that oblique incidence can be performed, and the detection of the welding line by adopting the horizontal shear wave can be realized;
(6) the sound absorption material is added at the end part of the wedge block, so that redundant sound waves in the wedge block are eliminated, and the detection precision is improved;
(7) because the wedge block and the transducer are detachably combined, one transducer can be matched with a plurality of wedge blocks with different angles, and the defects of different parts in a welding seam can be detected.
Drawings
Fig. 1 is a sectional view in a front view direction of the present invention;
fig. 2 is a schematic top view of the present invention;
FIG. 3 is a schematic view of the measurement principle of the present invention;
in the figure, 1 is a shell, 2 is a permanent magnet, 3 is a magnetic induction coil, 4 is a magnetic induction sheet, 5 is a signal line connector, 6 is an epoxy resin coupling layer, 7 is a wedge block, 8 is a sound absorption layer, and 9 is a bolt.
Detailed Description
The present invention will be described in detail with reference to the following embodiments. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that various changes and modifications can be made by one skilled in the art without departing from the spirit of the invention. These all belong to the protection scope of the present invention.
Example 1
A horizontal shear wave transducer for detecting a coarse crystal material welding seam is shown in figure 1 and comprises a transducer body, a shell 1 for packaging the transducer body, a wedge 7 for bearing the transducer body and an acoustic absorption layer 8 connected to the end part of the wedge 7. The transducer body comprises a permanent magnet 2 arranged on an inclined plane of a wedge 7, a magnetic induction coil 3 arranged in the permanent magnet 2, a magnetic induction sheet 4 attached to the lower surface of the magnetic induction coil 3, an epoxy resin coupling layer 6 attached to the lower surface of the magnetic induction sheet 4, and a signal wire connector 5 connected with the magnetic induction coil 3.
The function of each part in this embodiment is: a housing 1 for enclosing the transducer body structure; the permanent magnet 2 is used for generating a horizontal bias magnetic field; the magnetic induction coil 3 is used for generating an eddy current and a variable magnetic field, and receiving and exciting a horizontal shear wave signal; the magnetic induction sheet 4 generates magnetostrictive vibration under the action of the permanent magnet and the magnetic induction coil to excite horizontal shear waves; the signal wire joint 5 is used for transmitting magnetic induction coil signals; the epoxy resin coupling layer 6 is used for achieving impedance matching between the magnetic induction sheet and the wedge block; the wedge 7 is used for transmitting horizontal shear waves into the welding seam at a certain angle; the sound absorption layer 8 is used for eliminating redundant sound waves in the wedge block; the bolt 9 is used to fix the transducer to the wedge.
Wherein, the wedge 7 is made of organic glass; the angle between the inclined plane of the wedge 7 and the bottom surface is 45 deg.. The contact surfaces of the sound absorption layer 8 and the wedge 7 are rectangular teeth matched with each other; the material is sound-absorbing material. The permanent magnet 2 is a U-shaped magnet and is made of neodymium iron boron permanent magnet 2. The magnetic induction coil 3 is a folding annular copper coil, and the number of turns of the magnetic induction coil is 40. The length direction of the magnetic induction sheet 4 is in contact connection with the N pole and the S pole of the permanent magnet 2, and two end parts of the magnetic induction sheet 4 in the length direction are in contact connection with the N pole and the S pole of the permanent magnet 2 respectively; the width of the magnetic induction sheet 4 is 50 mm; the thickness of the magnetic induction sheet 4 is 0.25 mm; the magnetic induction sheet 4 is made of iron-cobalt alloy or nickel with the purity of 99.99%. The epoxy resin coupling layer 6 is made of epoxy resin quick-drying adhesive and is used for transmitting horizontal shear waves into the wedge block. The signal wire joint 5 has 40 interface pins; the signal wire joint 5 is matched with the magnetic induction coil 3 and used for transmitting and receiving electric signals. The material of shell 1 is non-wave-conducting material, and four screw holes are processed on the inclined plane of voussoir, and shell 1 is fixed in on the inclined plane of voussoir 7 through 4 bolts 9.
In the embodiment, the probe can detect the weld joint of the coarse-grained material, the horizontal shear wave oblique incidence with different angles can be realized according to different wedge block angles, and the incidence angle of the probe in the embodiment is 45 degrees. During the detection, a probe test is carried out by using a coarse-grained material reference block, as shown in fig. 3. And the probe excites horizontal shear waves to penetrate through transverse through holes in the middle and on the other side of the weld joint detection weld joint, the 6 transverse through holes are respectively detected, and the sound path of each transverse through hole is recorded. And comparing the detection result with the theoretical sound wave propagation sound path, and displaying that the measured sound path is consistent with the theoretical sound path, thereby indicating that the excited horizontal shear wave is not influenced by coarse grains in the welding seam to deflect. Therefore, the probe can be used for detecting the coarse-grained material weld joint, and the detection method is consistent with that of a conventional oblique probe, namely, the probe is perpendicular to the weld joint to perform sawtooth scanning.
The shear horizontal wave is a transverse wave in which the direction of particle vibration is parallel to the surface of the workpiece. When the traditional ultrasonic is used for detecting a coarse-grained material welding seam, the propagation direction of sound waves can be changed and a large number of clutter signals are generated due to the fact that the grains of the welding seam are large. The horizontal shear wave is slightly influenced by the coarse-grained material due to the fact that the vibration direction is different from the transverse wave, and the horizontal shear wave is an ideal coarse-grained material welding line detection waveform. In this example, the weld joint was detected by using the horizontal shear wave, but the horizontal shear wave excited by magnetostriction is not incident obliquely, and the weld joint cannot be detected. In the embodiment, the wedge block is adopted to realize oblique incidence of horizontal shear waves, so that the detection of the welding seam of the coarse-grained material is realized.
In the embodiment, the horizontal shear wave is adopted to detect the welding seam, so that compared with the traditional ultrasonic detection, the detection precision is higher, and the result is more accurate; the incidence direction of the horizontal shear wave is changed by adopting the wedge block, so that oblique incidence can be performed, and the detection of the welding line by adopting the horizontal shear wave can be realized; and a sound absorption material is added at the end part of the wedge block, so that redundant sound waves in the wedge block are eliminated, and the detection precision is improved.
Example 2
The main structure of this embodiment is the same as that of embodiment 1, except for the design parameters of the wedge and the parts inside the load-bearing transducer body. In this embodiment, the included angle between the inclined surface and the bottom surface of the wedge block is 60 degrees; meanwhile, the width of the magnetic induction sheet 4 is 25 mm; the thickness of the magnetic induction sheet 4 is 0.2mm, the number of turns of the magnetic induction coil 3 is 40, and the number of interface pins of the signal wire connector 5 matched with the magnetic induction coil 3 is 20.
Example 3
The main structure of this embodiment is the same as that of embodiment 1, except for the design parameters of the wedge and the parts inside the load-bearing transducer body. In the embodiment, the included angle between the inclined plane and the bottom surface of the wedge block is 70 degrees; meanwhile, the width of the magnetic induction sheet 4 is 50 mm; the thickness of the magnetic induction sheet 4 is 0.25mm, the number of turns of the magnetic induction coil 3 is 100 turns, and the number of interface pins of the signal wire connector 5 matched with the magnetic induction coil 3 is 40.
Example 4
The main structure of this embodiment is the same as that of embodiment 1, except for the design parameters of the wedge and the parts inside the load-bearing transducer body. In the embodiment, the included angle between the inclined plane and the bottom surface of the wedge block is 27 degrees; meanwhile, the width of the magnetic induction sheet 4 is 75 mm; the thickness of the magnetic induction sheet 4 is 0.1mm, the number of turns of the magnetic induction coil 3 is 20 turns, and the number of interface pins of the signal wire connector 5 matched with the magnetic induction coil 3 is 40.
Example 5
The main structure of this embodiment is the same as that of embodiment 1, except for the design parameters of the wedge and the parts inside the load-bearing transducer body. In the embodiment, the included angle between the inclined plane and the bottom surface of the wedge block is 70 degrees; meanwhile, the width of the magnetic induction sheet 4 is 75 mm; the thickness of the magnetic induction sheet 4 is 0.3mm, the number of turns of the magnetic induction coil 3 is 100 turns, and the number of interface pins of the signal wire connector 5 matched with the magnetic induction coil 3 is 40.
The foregoing description of the specific embodiments of the invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by those skilled in the art within the scope of the appended claims without departing from the spirit of the invention.
Claims (10)
1. A horizontal shear wave transducer for detecting a coarse-grained material weld joint comprises a transducer body and a shell (1) used for packaging the transducer body,
it is characterized in that the preparation method is characterized in that,
the transducer further comprises a wedge block (7) for carrying the transducer body and a sound absorption layer (8) connected to the end of the wedge block (7).
2. The shear-horizontal wave transducer for the detection of the welding seam of the macrocrystalline material as claimed in claim 1, wherein the wedge block (7) is made of organic glass or carbon steel; the included angle between the inclined plane of the wedge block (7) and the ground is 27-70 degrees.
3. The shear-horizontal wave transducer for the detection of the welding seam of the macrocrystalline material as the claim 1 is characterized in that the contact surfaces of the sound absorption layer (8) and the wedge block (7) are rectangular teeth matched with each other; the material is sound-absorbing material.
4. The shear horizontal wave transducer for weld detection of coarse grain materials according to claim 1, characterized in that the transducer body comprises a permanent magnet (2) arranged on the inclined plane of the wedge block (7), a magnetic induction coil (3) arranged inside the permanent magnet (2), a magnetic induction sheet (4) attached to the lower surface of the magnetic induction coil (3), an epoxy resin coupling layer (6) attached to the lower surface of the magnetic induction sheet (4), and a signal line connector (5) connected with the magnetic induction coil (3).
5. The shear-horizontal wave transducer for weld inspection of coarse-grained materials according to claim 4, characterized in that the permanent magnet (2) is a U-shaped magnet made of NdFeB permanent magnet (2).
6. The shear-horizontal wave transducer for weld detection of coarse grained materials according to claim 4, characterized in that the magnetic induction coil (3) is a folded annular copper coil with 20-100 turns.
7. The shear-horizontal wave transducer for weld detection of coarse grained materials according to claim 6, characterized in that the number of interface pins of the signal wire connector (5) is matched with the number of turns of the magnetic induction coil (3).
8. The shear-horizontal wave transducer for the weld detection of the macrocrystalline material is characterized in that the length direction of the magnetic induction sheets (4) is in the N pole and S pole directions of the permanent magnet (2), and two ends of the magnetic induction sheets (4) in the length direction are respectively in contact connection with the N pole and S pole of the permanent magnet (2);
the width of the magnetic induction sheet (4) is 25-75 mm;
the thickness of the magnetic induction sheet (4) is 0.1-0.3 mm;
the magnetic induction sheet (4) is made of iron-cobalt alloy or nickel with the purity of 99.99%.
9. The shear-horizontal wave transducer for weld inspection of coarse-grained materials according to claim 4, characterized in that the epoxy coupling layer (6) is prepared by epoxy quick-drying adhesive.
10. The shear-horizontal wave transducer for weld inspection of coarse grained materials according to claim 1, characterized in that the housing (1) is made of non-conductive material, and the housing (1) is fixed on the inclined surface of the wedge (7) by bolts (9).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920773858.XU CN210221906U (en) | 2019-05-27 | 2019-05-27 | Horizontal shear wave transducer for detecting coarse-grained material welding seam |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920773858.XU CN210221906U (en) | 2019-05-27 | 2019-05-27 | Horizontal shear wave transducer for detecting coarse-grained material welding seam |
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| Publication Number | Publication Date |
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| CN210221906U true CN210221906U (en) | 2020-03-31 |
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| CN201920773858.XU Expired - Fee Related CN210221906U (en) | 2019-05-27 | 2019-05-27 | Horizontal shear wave transducer for detecting coarse-grained material welding seam |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110057913A (en) * | 2019-05-27 | 2019-07-26 | 上海市特种设备监督检验技术研究院 | A kind of horizontal shear wave transducer for coarse grain material weld seam detection |
-
2019
- 2019-05-27 CN CN201920773858.XU patent/CN210221906U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110057913A (en) * | 2019-05-27 | 2019-07-26 | 上海市特种设备监督检验技术研究院 | A kind of horizontal shear wave transducer for coarse grain material weld seam detection |
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20200331 Termination date: 20210527 |