A compact small-diameter front end of a water-displacement wedge

Abstract

This invention proposes a compact, small-diameter front end for a water-displacement wedge, solving the problem that existing scanners using hard wedges are insufficient for detecting fillet welds in smaller pipe and tube sheet sizes. The main solution includes a small-diameter pipe and a tube sheet, with the outer wall of the small-diameter pipe integrally connected to the tube sheet via a weld. A scanner is inserted into the small-diameter pipe at the corresponding weld. The scanner comprises a front end body and a probe, a crystal array element, and a water-displacement wedge embedded within it. A signal cable is electrically connected to the top of the probe. The inner wall of the front end body is fixed to the probe with screws. The water-displacement wedge is adjacent to the probe, and its top is connected to the outside via a water injection pipe. The crystal array element is located adjacent to the water-displacement wedge and the probe, and it works in conjunction with the probe to perform phased array detection of the weld between the small-diameter pipe and the tube sheet.

Description

Technical Field

[0001] This utility model relates to the technical field of fillet weld inspection equipment, and in particular to a compact small-diameter front end of a water-displacement wedge. Background Technology

[0002] Ultrasonic testing is one of the most commonly used non-destructive testing methods for fillet welds. It detects defects by measuring the time and energy of the echoes in the fillet weld using an ultrasonic testing instrument. The ultrasonic testing procedure for fillet welds includes preparation, scanning the fillet weld, data analysis, and result recording. Ultrasonic testing is an efficient and reliable method for inspecting fillet welds and is widely used in various industries.

[0003] For inspecting fillet welds in tubes and tube sheets with even smaller dimensions, it is necessary to further reduce the size of the front end of the phased array ultrasonic scanning system for fillet welds in tubes and tube sheets. However, the existing hard wedge front end structure is not suitable, and it is very difficult to further reduce the size of the front end, which has already adopted a compact design.

[0004] To address this issue, we propose a compact, small-diameter front end for a water-displacement wedge. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the defects of the existing technology. This utility model proposes a compact small-diameter front end of a water-substituted wedge, which uses water instead of polystyrene as the wedge material. Since the ultrasonic velocity of water is lower, the thickness of the wedge can be reduced, thereby reducing the diameter of the front end.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is: a compact small-diameter front end of a water-displacing wedge, including a small-diameter pipe and a tube sheet. The outer wall of the small-diameter pipe is integrally connected to the tube sheet through a weld. A scanner is inserted into the small-diameter pipe at the corresponding weld. The scanner includes a front end body and a probe, a crystal array element, a water seal, and a water-displacing wedge built into the front end body. A signal cable is electrically connected to the top of the probe. The inner wall of the front end body is fixed to the probe by screws. The water-displacing wedge is adjacent to the probe and is connected to it through a water injection pipe for water injection, which is simultaneously sealed by the water seal. The crystal array element is located adjacent to the water-displacing wedge and the probe, and is used to cooperate with the probe to perform phased array detection at the weld between the small-diameter pipe and the tube sheet.

[0007] Furthermore, both the signal cable and the water injection pipe pass through the water seal.

[0008] Furthermore, the thickness of the water-displacement wedge is 3.43 mm.

[0009] Furthermore, the diameter of the front end body cross section is 14.5mm-14.6mm.

[0010] Furthermore, the inner diameter of the small-diameter pipe is not less than 15mm, and the weld size between the small-diameter pipe and the tube sheet is φ19×2mm.

[0011] Compared with the prior art, the beneficial effects of this utility model include: by changing the material of the probe wedge, water is used instead of polystyrene as the wedge material. Since the ultrasonic velocity of water is lower, the thickness of the wedge can be reduced, thus reducing the diameter of the front end. On the other hand, by using flexible water instead of rigid polystyrene, the hard wedge will not come into direct contact with the pipe wall, and the change in the condition of the pipe wall during the rotation of the front end will not affect the position of the probe. Thus, the spring balancing system can be eliminated, further reducing the diameter of the front end. Attached Figure Description

[0012] The disclosure of this utility model is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. In the drawings, the same reference numerals are used to refer to the same parts. Wherein:

[0013] Figure 1 The schematic diagram shows an overall structural schematic diagram according to one embodiment of the present invention;

[0014] Figure 2 The schematic diagram shows a front-end structure according to one embodiment of the present invention;

[0015] Figure 3 The illustration schematically shows a method proposed according to one embodiment of the present invention. Figure 1 Sectional view along axis AA;

[0016] Figure 4 The illustration shows a phased array scan diagram of a phased array tube sheet fillet weld of a hard wedge block according to a background embodiment of the present invention.

[0017] The following are the labels in the diagram: 1. Front end body; 2. Probe; 3. Screw; 4. Water-filled wedge; 5. Signal cable; 6. Water injection pipe; 7. Chip array element; 8. Spring; 9. Hard wedge; 10. Weld; 11. Small diameter pipe; 12. Tube sheet; 13. Water seal. Detailed Implementation

[0018] It is readily understood that, based on the technical solution of this utility model, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of this utility model. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative descriptions of the technical solution of this utility model and should not be considered as the entirety of this utility model or as limitations or restrictions on the technical solution of this utility model.

[0019] According to one embodiment of the present invention, in conjunction with Figures 1-3 As shown.

[0020] In this embodiment, a compact small-diameter front end of a water-displacement wedge includes a small-diameter pipe 11 and a tube sheet 12. The outer wall of the small-diameter pipe 11 is connected to the tube sheet 12 by a weld 10. A scanner is inserted into the small-diameter pipe 11 at the corresponding weld 10. The scanner includes a front end body 1 and a probe 2, a wafer array element 7, a water seal 13, and a water-displacement wedge 4 built into the front end body 1. The top of the probe 2 is electrically connected to a signal cable 5 to the exposed small-diameter pipe 11. The inner wall of the front end body 1 is connected and fixed to the probe 2 by screws 3. The water-displacement wedge 4 is adjacent to the probe 2, and its top is connected to the outside through a water injection pipe 6. The wafer array element 7 is located adjacent to the water-displacement wedge 4 and the probe 2, and is used to cooperate with the probe 2 to perform phased array detection at the weld 10 between the small-diameter pipe 11 and the tube sheet 12.

[0021] The specific dimensions of the front-end body 1 and the water-displacing wedge block 4 are implemented based on the following principles and calculations:

[0022] The inner wall of the small-diameter pipe 11 was scanned, and the fillet weld 10 of the pipe sheet 12 of the small-diameter pipe 11 was subjected to phased array testing using the vertical incidence method. The ultrasonic double-repetition method was used, and the calculation of the relevant detection sound path and wedge thickness is as follows:

[0023] Taking the fillet weld 10 of the tube sheet 12 of the φ19×2mm pipe as an example, the sound path YG in the steel should not be less than the pipe wall thickness t + weld 10 width w1 + heat-affected zone width w2, that is: YG=t+w1+w2=2+3+1=6mm.

[0024] During the design, the sound path YX of the wedge block should be no less than twice the sound path in the steel, with an appropriate margin 'a' added.

[0025] That is: YX = YG × 2 + a = 6 × 2 + 2 = 14 mm

[0026] If the wedge is made of polystyrene, the formula for calculating the polystyrene thickness TJ is:

[0027] TJ = Polystyrene sound velocity × Steel thickness / Steel sound velocity = 2350 × 14 / 5950 = 5.53mm

[0028] If the wedge material is changed from polystyrene to water, the formula for calculating the water layer thickness Ts is:

[0029] Ts = Polystyrene thickness × Water sound velocity / Polystyrene sound velocity = 5.53 × 1450 / 2350 = 3.43 mm

[0030] This means that this single improvement can reduce the front diameter by 2.1 mm. Furthermore, since water is flexible, the spring 8 balancing system can be eliminated, further reducing the front diameter by 2.1 mm. Therefore, the front diameter can be reduced by a total of 4.2 mm.

[0031] The original phased array scanning system for the tube sheet 12 fillet weld 10, which uses polystyrene wedges, has a scanner front end designed with a compact structure. The minimum outer diameter is 14.5-14.6 mm, the minimum inner diameter that can reach into the small-diameter pipe 11 to scan the weld 10 is 15 mm, and the smallest size of the tube sheet 12 fillet weld 10 that can be detected is φ19×2 mm.

[0032] By replacing polystyrene wedges with water, the outer diameter of the front end of the phased array scanning system for tube-to-tube sheet fillet weld 10 can be reduced by 4.2 mm, from 14.5 mm to 10.3 mm. The smallest diameter tube 11 capable of reaching inside the tube to scan weld 10 is 10.7 mm, thus enabling its use for inspecting φ15×2 mm tube-to-tube sheet fillet weld 10. This is a significant improvement. Further optimization of the front end structure details can further reduce the minimum size of the inspectable tube-to-tube sheet fillet weld 10.

[0033] The technical scope of this utility model is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this utility model, and all such modifications and variations should fall within the protection scope of this utility model.

Claims

1. A compact small-diameter front end of a water-dispatch wedge, comprising a small-diameter pipe and a tube sheet, wherein the outer wall of the small-diameter pipe is integrally connected to the tube sheet via a weld, and a scanner is inserted into the small-diameter pipe at the corresponding weld, characterized in that: The scanner includes a front-end body and a probe, a crystal array element, a water seal, and a water-substitute wedge built into the front-end body. The top of the probe is electrically connected to a signal cable. The inner wall of the front-end body is connected and fixed to the probe by screws. The water-substitute wedge is adjacent to the probe and is connected to it through a water injection pipe for water injection, which is simultaneously sealed by the water seal. The crystal array element is located adjacent to the water-substitute wedge and the probe, and is used to cooperate with the probe to perform phased array detection on the weld seam of the small-diameter pipe and the tube sheet.

2. The compact small-diameter front end of a water-dispatch wedge according to claim 1, characterized in that: Both the signal cable and the water injection pipe pass through the water seal.

3. The compact small-diameter front end of a water-dispatch wedge according to claim 1, characterized in that: The thickness of the water-displacement wedge is 3.43 mm.

4. The compact small-diameter front end of a water-dispatch wedge according to claim 1, characterized in that: The diameter of the front end body cross section is 14.5mm-14.6mm.

5. The compact small-diameter front end of a water-dispatch wedge according to claim 1, characterized in that: The inner diameter of the small-diameter pipe is not less than 15mm, and the weld size between the small-diameter pipe and the tube sheet is φ19×2mm.

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