CN217561412U

CN217561412U - Fillet weld ultrasonic detection's reference test block

Info

Publication number: CN217561412U
Application number: CN202221337306.2U
Authority: CN
Inventors: 王沛
Original assignee: Huaneng Gansu Xigu Thermal Power Co ltd
Current assignee: Huaneng Gansu Xigu Thermal Power Co ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-10-11
Anticipated expiration: 2032-05-31

Abstract

A reference block for fillet weld ultrasonic detection. At present, magnetic powder or penetration detection is generally adopted for conventional nondestructive fillet welds, the methods only finish detection on the surfaces of the fillets and can find and eliminate the defects that the surfaces of the fillets exceed standards, but important parts need to detect the internal quality of the fillet welds. The cross section of the comparison test block is in the shape of a fillet weld, an artificial defect A and two artificial defects B are machined on the steel block, the artificial defect A and the two artificial defects B are on an inclined line of 27.5 +/-2.5 degrees along the upper surface of the main plate, and the distance between the 3 artificial defects is 5mm. The utility model is used for fillet weld ultrasonic testing.

Description

Fillet weld ultrasonic detection's reference test block

The technical field is as follows:

the utility model relates to a fillet weld ultrasonic detection's reference test piece.

Background art:

in the construction process of large-scale projects such as thermal power plants, a large number of fillet welds exist in equipment installation and structural member assembly. At present, magnetic powder or penetration detection is generally adopted for routine nondestructive fillet welding, the methods only finish detection on the surface of the fillet welding, the overproof defect of the surface of the fillet welding can be found and eliminated, but important parts need to test the internal quality of the fillet welding.

The utility model has the following contents:

the utility model aims at providing a fillet weld ultrasonic detection's reference test block.

The above purpose is realized by the following technical scheme:

the utility model provides a fillet weld ultrasonic testing's reference test block, this reference test block is the steel block of cross sectional shape for the fillet weld shape, the steel block on process an artificial defect A and two artificial defect B, artificial defect A and two artificial defect B are along mainboard upper surface 27.5 +/-2.5 on the slash, 3 artificial defects are apart from each other for 5mm

The fillet weld ultrasonic detection reference block is characterized in that the artificial defect B is a circle with the diameter of 2mm, and the height of the artificial defect triangle A is 2mm.

The fillet weld ultrasonic detection reference block is characterized in that the artificial defect A is triangular and the height of the artificial defect A is 2mm.

Has the advantages that:

1. the utility model discloses reference block repeatedly usable adopts the preparation of high-quality carbon steel, and economic nature is high, can follow web unilateral and accomplish fillet weld ultrasonic testing work, and the suitability is strong, and the using value is high.

2. The utility model discloses the reference block reliability is high, can effectively avoid welding defect's hourglass to examine or the erroneous judgement, and the process is simple, and strong adaptability, popularization and application are worth highly.

3. The utility model discloses DAC curve preparation is accomplished to the reference block, and parameter debugging is accurate, and the reliability is high.

Description of the drawings:

FIG. 1 is a front view of the present invention;

fig. 2 is a top view of the present invention;

FIG. 3 is a schematic fillet weld anatomy;

FIG. 4 is a schematic view of a direct-wave primary scan;

FIG. 5 is a schematic view of a direct-wave quadratic wave scan;

FIG. 6 is one of the schematic distance-amplitude curves;

FIG. 7 is a second graph of distance versus amplitude;

FIG. 8 is one of the schematic diagrams of reflected waves occurring in a region;

FIG. 9 is a second schematic diagram of a region showing reflected waves;

FIG. 10 is a third schematic diagram of a region in which a reflected wave occurs;

FIG. 11 is a fourth illustration of a region showing reflected waves;

FIG. 12 is a schematic diagram of the distance traveled by the direct wave probe;

FIG. 13 is a schematic diagram of the displacement of a secondary wave probe.

The specific implementation mode is as follows:

example 1:

the utility model provides a fillet weld ultrasonic testing's reference test block, this reference test block is the steel block of cross sectional shape for the fillet weld shape, the steel block on process an artificial defect A and two artificial defect B, artificial defect A and two artificial defect B along mainboard upper surface 27.5 +/-2.5 on the slash, 3 artificial defects are 5mm apart from each other.

Example 2:

according to the reference block for fillet weld ultrasonic testing in the embodiment 1, the artificial defect B is a circle with the diameter of 2mm, and the height of the artificial defect triangle A is 2mm.

Example 3:

according to the reference block for fillet weld ultrasonic detection in the embodiment 1, the artificial defect A is a triangle, and the height of the artificial defect A is 2mm.

The detection method of the reference block for fillet weld ultrasonic detection comprises the following steps:

the method comprises the following steps: scanning root defects and defects within a range of 1/2 wall thickness from the root by adopting direct waves, scanning defects within a range of near surface and 1/2 wall thickness from the surface by adopting secondary waves, drawing a DAC curve according to 3 points, determining a scanning line, a quantitative line and a rejection line, and using the DAC curve as fillet weld detection, as shown in figure 4;

wherein:

h1: thickness of the main board in mm

H2: fillet thickness in mm

H3: web thickness in mm, H3 < H1

4: an ultrasonic probe;

step two: detecting the defects of the root and the defects within the range of 1/2 of the wall thickness from the root by adopting direct wave, placing a probe on a web plate, directly reflecting an acoustic beam emitted by an ultrasonic probe by the defects of the root, and judging whether the defects exceed the standard or not according to a DAC curve, as shown in figure 5;

step three: scanning defects in the range of the wall thickness close to the surface and 1/2 of the wall thickness away from the surface by using secondary waves, placing the probe on the web, reflecting the sound beam emitted by the ultrasonic probe by the web to form secondary wave detection, and judging whether the secondary wave detection exceeds the standard or not according to the DAC curve.

And (3) test block preparation: a120 mm (L1) x 120mm (L2) x 80mm (L3) high-quality carbon steel forging is machined mechanically into a piece of high-quality carbon steel forging with the cross section in the shape of an actual fillet weld as shown in figure 1, wherein a main plate is H1, the height of a fillet weld leg is H2, and the thickness of a web plate is H3.

And in the second part, machining an artificial defect A, B on the machined test block with the cross section in the shape of the fillet weld by adopting a mechanical mode. The artificial defect A is a triangle, the center position is at a position away from the bottom edge H1, and defects such as incomplete root welding, incomplete fusion and the like are simulated; the artificial defects B are circular, the defects such as air holes in the middle of the simulated welding line, slag inclusion and the like are 2 in total, and are sequentially distributed in the simulated fillet welding line along an oblique line of 27.5 +/-2.5 degrees on the upper surface of the main plate, as shown in a front view of fig. 1, the distance between the 3 artificial defects is 5mm, and the depth is 40mm (L4). The diameter of the artificial defect circle B is 2mm, and the height of the artificial defect triangle A is 2mm, as shown in figures 1 and 2;

wherein:

h1: thickness of the main board in mm

H2: fillet thickness in mm

H3: web thickness in mm, H3 < H1

L1: test block length in mm

L2: test block height in mm, L1= L2

L3: test block width in mm

L4: length of artificial defect in mm, L3=2L4

A: triangular artificial defect

B: circular artificial defects;

a schematic view of the weld is shown in figure 3,

wherein:

h1: thickness of the main board in mm

H2: fillet thickness in mm

H3: web thickness in mm, H3 < H1

Main board (Black outline area)

2: fillet weld (red outline region), region to be inspected

3: a web (green outline area) for placing the probe;

distance-amplitude curve preparation:

the utility model is used for drawing 1 basic curve for 3 holes with phi 2 multiplied by 40mm on the reference block, as shown in figure 6;

wherein:

1 (point a): comparing the triangular artificial defects at the bottom of the test block;

2 (point B1): comparing the middle circular artificial defects of the test block;

3 (point B2): comparing the circular artificial defects on the inclined surface of the test block;

on the basis of 1 basic curve (pink) drawn in fig. 6, the curve is adjusted according to the gain (dB) value in table 1, and three curves for fillet weld ultrasonic detection are obtained: scanning lines (green), quantitative lines (blue) and waste judgment lines (red) are shown in figure 7 and are used as the judgment basis for the fillet weld ultrasonic detection defects.

TABLE 1 fillet weld detection sensitivity

Name of curve	Scanning line (EL)	Quantitative line (SL)	Waste judgment line (RL)
				Gain adjustment	Ф2×40-16dB	Ф2×40-10dB	Ф2×40-2dB

Wherein: EL: scanning line

SL: quantitative line

RL: waste judgment line

According to the 3 drawn curves, the coordinate interface is divided into: and (3) sequentially judging the weld defects in the I, II and III areas according to the positions of the weld defect waves.

The method for judging the weld defects comprises the following steps:

reflected waves occurring in the region below zone i are not recorded, as shown in fig. 8;

and (3) region I: evaluating the area between the line and the quantitative line (including the quantitative line), and only measuring and recording the defect indication length when reflected waves appear in the area as shown in FIG. 9;

and (2) zone II: the area between the quantitative line and the discriminant line (including the discriminant line) is shown in fig. 10, and the reflection chamber is present in the area to measure the length of the defect indication, so as to determine whether the defect indication is qualified according to the length.

Zone III: and judging the area above the waste line, and judging that the welding quality is unqualified when the area has the defect reflected wave as shown in figure 11.

Defective reflection waves appear in the I area and the II area, and if cracks can be judged according to experience, unqualified welding seams are directly judged;

weld detection registration determination basis:

and (3) the fillet weld ultrasonic detection qualification standard is as follows: grade I;

the weld quality ratings are shown in table 2.

TABLE 2 quality grading Table

Wherein: t specimen thickness in mm.

Moving distance of the welding seam detection probe:

detecting direct waves: the moving distance S1 of the probe is more than or equal to 0.75P as shown in figure 12;

secondary wave detection: the moving distance S2 of the probe is more than or equal to 1.25P as shown in figure 13;

wherein: s1: the moving distance of the direct wave probe is unit mm;

s1: moving distance of the secondary wave probe in unit mm;

p: span, unit mm;

k: the tangent value of the refraction angle of the probe;

t: the thickness of the test piece in mm.

Claims

1. A reference block for fillet weld ultrasonic detection is characterized in that: this reference block is the steel block that cross sectional shape is the fillet weld shape, the steel block on process an artificial defect A and two artificial defects B, artificial defect A and two artificial defects B along mainboard upper surface 27.5 on 2.5 inclined lines, 3 artificial defects are 5mm apart from each other.

2. The reference block for ultrasonic testing of fillet welds according to claim 1, wherein: the artificial defect B is a circle with the diameter of 2mm, and the height of the artificial defect triangle A is 2mm.

3. The reference block for ultrasonic testing of fillet welds according to claim 1, wherein: the artificial defect A is a triangle, and the height of the artificial defect A is 2mm.