Weld joint flaw detection construction method

Abstract

The invention relates to a weld seam flaw detection construction method which comprises the following steps: providing an ultrasonic detector, attaching the ultrasonic detector to a weld seam of a to-be-detected piece, starting the ultrasonic detector, and performing ultrasonic detection on the weld seam through the ultrasonic detector to obtain a first echo amplitude; moving the ultrasonic detector back and forth along the surface of the to-be-detected piece, starting the ultrasonic detector, and performing ultrasonic detection on the welding seam through the ultrasonic detector to obtain a second echo amplitude; and providing a standard echo amplitude range, comparing the standard echo amplitude with the first echo amplitude and the second echo amplitude, and if the first echo amplitude or the second echo amplitude is not within the standard amplitude range, determining that the weld joint welding is unqualified, so that the use is convenient, and the operation is simple.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, in particular to a welding seam flaw detection construction method. Background Art

[0002] During the construction process, welding is often used to fix rods or plates together, but the weld structure is complex and the root of the weld is not fully penetrated, which is a common defect. If the workpiece with incomplete weld is directly used in the building structure, the strength of the workpiece may be insufficient, which may cause problems in the project. Magnetic particle testing (MT) or X-ray testing (RT) is usually used to check the weld of the workpiece. Magnetic particle testing cannot detect austenitic stainless steel materials and welds welded with austenitic stainless steel electrodes, nor can it detect non-magnetic materials such as copper, aluminum, magnesium and titanium. It is difficult to detect shallow scratches on the surface, deep holes, and delamination and folding with an angle of less than 20° with the surface of the workpiece. Due to the radiation, X-ray testing requires the surrounding workers to be cleared and a control area to be set up during the inspection, which greatly wastes time and manpower. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a weld flaw detection construction method. By using an ultrasonic detector to inspect the weld, the difficulty of checking whether the weld is not penetrated is greatly reduced, so as to reduce the labor intensity of the constructors, and the operation is simple and easy to use.

[0004] The technical solution to achieve the above purpose is a weld flaw detection construction method, comprising the following steps:

[0005] Providing an ultrasonic detector, attaching the ultrasonic detector to the weld of the part to be inspected, starting the ultrasonic detector, and performing ultrasonic inspection on the weld by the ultrasonic detector to obtain a first echo amplitude;

[0006] Move the ultrasonic detector back and forth along the surface of the part to be detected, start the ultrasonic detector, and use the ultrasonic detector to perform ultrasonic detection on the weld to obtain a second echo amplitude;

[0007] A standard echo amplitude range is provided, and the standard echo amplitude is compared with the first echo amplitude and the second echo amplitude. If the first echo amplitude or the second echo amplitude is not within the standard amplitude range, the weld is unqualified.

[0008] Furthermore, the ultrasonic detector uses a shear wave oblique probe for detection.

[0009] Furthermore, when the ultrasonic detector moves, the shear wave oblique probe is controlled to deflect at an angle of 10°.

[0010] Furthermore, the shear wave oblique probe is polished before the weld is inspected by the ultrasonic detector.

[0011] Furthermore, before the weld is inspected by the ultrasonic detector, the welding spatter around the weld is polished off.

[0012] Furthermore, before the weld is inspected by the ultrasonic detector, paste is brushed around the weld.

[0013] Furthermore, the paste is prepared from antelope methyl cellulose.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] By using an ultrasonic detector to inspect the weld, the difficulty of checking whether the weld is not fully penetrated is greatly reduced, so as to reduce the labor intensity of the constructors. The operation is simple and easy to use. Preferably, during the inspection, a paste prepared by methyl cellulose is brushed on the periphery of the weld to ensure that the probe can fit the part to be inspected. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention provides a structural schematic diagram of a weld to be inspected component and a weld in a weld flaw detection construction method.

[0017] Figure 2 The detection effect of the ultrasonic detector of the weld flaw detection construction method of the present invention Figure 1 .

[0018] Figure 3 The detection effect of the ultrasonic detector of the weld flaw detection construction method of the present invention Figure 2 .

[0019] Figure 4 The detection effect of the ultrasonic detector of the weld flaw detection construction method of the present invention Figure 3 .

[0020] Legend: 1. Part to be tested; 2. Weld; 3. Ultrasonic detector. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0022] See also Figure 1A weld flaw detection construction method includes the following steps: providing an ultrasonic detector 3, attaching the ultrasonic detector 3 to the weld 2 of a to-be-detected part 1, the ultrasonic detector 3 emitting a direct wave toward the weld 2, the direct wave goes back and forth between the weld 2 and the ultrasonic detector 3 to form a first echo, the ultrasonic detector 3 receives the first echo to obtain a first echo amplitude; moving the ultrasonic detector 3 back and forth along the surface of the to-be-detected part 1, the ultrasonic detector 3 emitting a reflected wave toward the weld 2, the reflected wave goes back and forth between the inner wall of the to-be-detected part 1, the weld 2 and the ultrasonic detector 3 to form a second echo, the ultrasonic detector 3 receives the second echo to obtain a second echo amplitude; providing a standard echo amplitude range, comparing the standard echo amplitude with the first echo amplitude and the second echo amplitude, if the first echo amplitude or the second echo amplitude is not within the standard amplitude range, the welding of the weld 2 is unqualified.

[0023] In the present application, a preferred embodiment is that the part to be inspected 1 is formed by two connecting parts being spliced ​​in a T shape, and the weld 2 is arranged at the intersection of the T shape. When the ultrasonic detector 3 is used for inspection, the ultrasonic detector 3 is first arranged on the upper surface of the middle section, and the ultrasonic detector 3 is placed at the position of the weld 2, and the weld 2 is inspected by a direct wave, and then the ultrasonic detector 3 is controlled to slide in a direction away from the weld 2, and a reflected wave is emitted, and the reflected wave is reflected in the middle section to scan the weld 2; then the ultrasonic detector 3 is placed on the lower surface of the middle section, and the ultrasonic detector 3 is placed at the position of the weld 2, and the weld 2 is inspected by a direct wave, and then the ultrasonic detector 3 is controlled to slide in a direction away from the weld 2, and a reflected wave is emitted, and the reflected wave is reflected in the middle section to scan the weld 2; then the ultrasonic detector 3 is placed on the side of the part to be inspected 1 away from the middle section, and the ultrasonic detector 3 is controlled to perform a flat scan along the weld 2 area, and the scanning result is compared with the standard amplitude range to determine whether the weld 2 is qualified.

[0024] Preferably, when the thickness of the test material is T=8-15mm; check the values ​​of the first echo amplitude and the second echo amplitude. When the echo amplitude (H) ≥ φ2*40-4dB, no matter how the defect length (l) of the weld 2 is, it is evaluated as unacceptable; when the echo amplitude (H) < φ2*40-14dB, no matter how the defect length (l) of the weld 2 is, it is evaluated as acceptable;

[0025] When the thickness of the test material is T = 8-15mm, and φ2*40-14dB ≤ echo amplitude (H) < φ2*40-4dB, and the following conditions are met, it is considered acceptable, otherwise it is unacceptable:

[0026] 1) Requirements for individual (including group) defects:

[0027] ①φ2*40-4dB>H≥φ2*40-8dB and l<Tmm;

[0028] ②φ2*40-10dB>H≥φ2*40-14dB and l<1.5Tmm;

[0029] 2) Requirements for cumulative deficiencies

[0030] ①φ2*40-4dB>H≥φ2*40-8dB and l<Tmm;

[0031] ②φ2*40-10dB>H≥φ2*40-14dB and l<1.5Tmm;

[0032] When the thickness of the test material is T = 15-100mm, when the echo amplitude (H) ≥ φ2*40, regardless of the defect length (l), it is considered unacceptable; when the echo amplitude (H) < φ2*40-14dB, regardless of the defect length (l), it is considered acceptable;

[0033] When the thickness of the test material is T = 15-100mm, and φ2*40-14dB≤echo amplitude (H)<φ2*40, it is acceptable if the following conditions are met at the same time, otherwise it is unacceptable:

[0034] 1) Requirements for individual (including group) defects:

[0035] ①φ2*40>H≥φ2*40-6dB and l<0.5Tmm

[0036] ②φ2*40-6dB>H≥φ2*40-10dB and l<Tmm

[0037] 2) Requirements for cumulative deficiencies

[0038] ①φ2*40>H≥φ2*40-6dB and l<0.5Tmm

[0039] ②φ2*40-6dB>H≥φ2*40-10dB and l<Tmm

[0040] Furthermore, the ultrasonic detector 3 uses a shear wave oblique probe for detection.

[0041] Furthermore, when the ultrasonic detector 3 is moving, the shear wave oblique probe is controlled to deflect by 10 degrees. Preferably, the shear wave oblique probe can be controlled to deflect by 10 to 15 degrees to increase the reception of echoes by the ultrasonic detector 3 .

[0042] Furthermore, the shear wave oblique probe is polished before the weld 2 is inspected by the ultrasonic detector 3. The shear wave oblique probe is polished to ensure that the probe can better inspect the part 1 to be inspected.

[0043] Furthermore, before the ultrasonic detector 3 detects the weld 2, the weld spatter around the weld 2 is polished off. The weld spatter is polished off to ensure that the ultrasonic detector 3 can detect accurately.

[0044] Furthermore, before the weld 2 is inspected by the ultrasonic detector 3, paste is applied around the weld 2. Preferably, during the inspection, paste prepared by methyl cellulose is applied around the weld 2 to ensure that the probe can fit the inspected piece 1.

[0045] Furthermore, the paste is prepared from antelope methyl cellulose.

[0046] The following is an explanation of the use process of a weld flaw detection construction method of the present invention.

[0047] Before testing, the welding spatter around the weld 2 needs to be polished clean. During testing, a paste prepared with antelope methyl cellulose is brushed on the periphery of the weld 2 to ensure that the probe can fit with the workpiece 1 to be tested. In order to meet the requirement of fitting the probe with the base material, the probe needs to be polished to meet the shape of the base material. The entire test area is scanned on the workpiece 1 to be tested using a shear wave oblique probe using a direct wave and a single reflection method. During the scanning process, the sound beam is ensured to move back and forth perpendicular to the weld 2, and the probe should also be rotated about 10°. After the scanning is completed, the entire test area is scanned obliquely and parallelly, and the echo amplitude received by the ultrasonic detector 3 is compared with the standard amplitude range to determine whether the weld 2 is qualified.

[0048] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A weld flaw detection construction method, characterized in that: The steps include: Providing an ultrasonic detector, attaching the ultrasonic detector to the weld of the part to be inspected, starting the ultrasonic detector, and performing ultrasonic inspection on the weld by the ultrasonic detector to obtain a first echo amplitude; Move the ultrasonic detector back and forth along the surface of the part to be detected, start the ultrasonic detector, and use the ultrasonic detector to perform ultrasonic detection on the weld to obtain a second echo amplitude; A standard echo amplitude range is provided, and the standard echo amplitude is compared with the first echo amplitude and the second echo amplitude. If the first echo amplitude or the second echo amplitude is not within the standard amplitude range, the weld is unqualified.

2. A weld flaw detection construction method according to claim 1, characterized in that: The ultrasonic detector uses a shear wave oblique probe for detection.

3. A weld flaw detection construction method according to claim 2, characterized in that: When the ultrasonic detector is moving, the shear wave oblique probe is controlled to deflect at an angle of 10°.

4. A weld flaw detection construction method according to claim 2, characterized in that: The shear wave oblique probe is polished before the weld is inspected by the ultrasonic detector.

5. The weld flaw detection construction method according to claim 1 is characterized in that: Before the weld is inspected by the ultrasonic detector, the weld spatter around the weld is polished.

6. A weld flaw detection construction method according to claim 1, characterized in that: Before the weld is inspected by the ultrasonic detector, paste is applied around the weld.

7. A weld flaw detection construction method according to claim 6, characterized in that: The paste is prepared from antelope methyl cellulose.

Images