CN101576535A - Incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves - Google Patents

Abstract

The invention belongs to an incomplete-fusion ultrasonic detection method for plug-in type pipe socket weld grooves, which is technically characterized in that a detection area is divided into three types of eight detection regions, the probe angles of the detection regions are respectively calculated to determine the K value of a probe by adopting big diameter pipe test blocks with the same material as the plug-in type pipe sockets and an HS-600a or USM-22 digital ultrasonic defect detector; and when the probe detects defects in a probe movement region, the incomplete fusion is judged when the position of the probe basically fits close with the corresponding positions of the horizontal distance of echoes at the maximum and minimum. The invention can select probes of different angles according to different types of detection regions and accurately and effectively detects incomplete fusion defects of pipe socket angle weld grooves by using the ultrasonic method, and has high accuracy, and convenient use, thereby improving the detectable rate of detection, reducing the safety hidden troubles in the running of the plug-in type pipe sockets to ensure the safe production of power.

Description

Incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves

Technical field

The invention belongs to the welding detection method, especially a kind of incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves.

Background technology

Station boiler equipment has used a large amount of plug-in type bases, and as plug-in type temperature, force pipe base, these plug-in type bases are welded by the person in charge and arm, and it in use phenomenon of rupture can occur, and accidents such as booster take place.By analysis, fracture place of plug-in type base all is in the groove position, and promptly being interacted to expand by welding incomplete fusion defective and structural stress forms cracking.Safety for guaranteeing that the power station produces eliminates safe hidden trouble, and need carry out Non-Destructive Testing to the weld seam of plug-in type base to find the weld seam inherent vice.

The planimetric map of plug-in type base fillet weld on being responsible for be oval, the groove plane be responsible for axial angle with the constantly variation of fillet weld trend, perpendicular to vertical tangent plane of fillet weld will by the infinitely-great ellipse of major axis gradually change into one just round.Because plug-in type base fillet weld structural reason adopts the conventional sense method to be difficult to accurately and efficiently it be carried out Non-Destructive Testing.For the Non-Destructive Testing of plug-in type base fillet weld, be a difficult point of Non-Destructive Testing always, also do not have at present a kind ofly can carry out the method for accurate and effective detection to it.

Summary of the invention

The objective of the invention is to overcome the deficiencies in the prior art, a kind of accurate and effective incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves is provided.

The present invention solves its technical matters and takes following technical scheme to realize:

A kind of incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves is characterized in that: this method comprises the steps:

(1). sensing range is divided into eight detection zones of three types: the charge shaft outside fillet weld is to lip-deep two symmetrical detection zones: first detection zone (A1) and the 5th detection zone (A5), main drive tube outside fillet weld is to lip-deep two symmetrical detection zones: four symmetrical detection zones between the 3rd detection zone (A3) and the 7th detection zone (A7) and above-mentioned four detection zones: second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8);

(2). determine the probe K value: calculate the head angle of three types of detection zones respectively,, can get under the condition of being responsible for inside surface formation primary event flaw detection, determine the probe K value at assurance incident acoustic beam according to probe wafer and frequency;

(3). select test block: adopt the large-diameter pipe test block identical with plug-in type base material, the test block material is A335P91;

(4). select defectoscope: adopt Chinese prestige HS-600a or USM-22 Digital Ultrasonic Flaw Detector;

(5). defectoscope is regulated: with one times be apart from amplitude curve with twice wall thickness degree of depth artificial defect hole echo 60% height line, with twice wall thickness degree of depth hole reflection echo 60%, and raising 6dB is as Scanning sensitivity;

(6). defect location: the probe moving area that on the person in charge of fillet weld periphery, draws, use probe to detect a flaw at the probe moving area, when probe positions is coincide in the relevant position of maximum and minimum value substantially with the echo level distance, promptly be judged to be incomplete fusion.

And, described first detection zone (A1), the 5th detection zone (A5), the 3rd detection zone (A3) and the 7th detection zone (A7) are the sector region of 60 degree, and described second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8) are the sector region of 30 degree.

And the person in charge at described plug-in type base angle is that ID457 * 50mm, arm are that φ 38 * 7mm and groove are temperature, the pressure base of 30-35 degree.

And the method for the head angle of described definite three types of detection zones is:

(1). first detection zone (A1) and the 5th detection zone (A5) according to groove angle, adopt the probe of 55-60 degree by normal butt-weld technology Calculation head angle;

(2). the 3rd detection zone (A3) and the 7th detection zone (A7) are by the mean value calculation of fillet weld outside groove lower extreme point angle and upper extreme point angle;

(3). the head angle of second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8) adopts the head angle of first detection zone (A1) and the 3rd detection zone (A3) or adopts the head angle of first detection zone (A1) and the intermediate value of the head angle of the 3rd detection zone (A3).

And described probe wafer is 9mm * 9mm wafer, and its frequency is the 2.5MHz frequency.

And described method of drawing the probe moving area on the person in charge of fillet weld periphery is:

(1). calculate the upper and lower end points horizontal level and the corresponding arc length of interior probe positions of first detection zone (A1) and the interior probe positions of the 3rd detection zone (A3) respectively;

(2). according to the pairing arc length value of upper and lower end points of the probe positions of the probe positions of first detection zone (A1) that calculates and the 3rd detection zone (A3), and on the plug-in type base, draw and be the probe moving area along two zones that line surrounded of weld seam trend.

Advantage of the present invention and good effect are:

This incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves is according to the characteristics of plug-in type base fillet weld, sensing range is divided into three types of eight detection zones, select the probe of different angles and use hyperacoustic method that the not molten defective of plug-in type base fillet weld groove is detected accurately and efficiently according to dissimilar detection zones, its accuracy height, easy to use, improved the recall rate of check, reduce the potential safety hazard that the plug-in type base is in operation, guaranteed electric power safety production.

Description of drawings

Fig. 1 is a grafting pressure base synoptic diagram;

Fig. 2 is that detection zone distributes and the probe positions synoptic diagram;

Fig. 3 is the incident acoustic wave synoptic diagram;

Fig. 4 is the detection faces synoptic diagram.

Embodiment

Below in conjunction with accompanying drawing the embodiment of the invention is further described.

The present invention is that ID457 * 50mm, arm are that φ 38 * 7mm and groove are that temperature, the pressure base fillet weld of 30-35 degree is that the example explanation is described with the person in charge.

Determining of detection method of the present invention: as shown in Figure 1, the plug-in type base is welded by the person in charge 1 and arm 2, forms fillet weld 3 in the groove welding back of 30-35 degree.Owing to the plug-in type base is to be welded after tube and tube is pegged graft, therefore, the planimetric map of weld seam on being responsible for is oval, shows as Fig. 2, and the groove plane changes at any time with person in charge's axial angle.When detecting, different probe incident acoustic beams and the angle of weld groove be owing to the influence of caliber, and change.Because the main incomplete fusion defective that detects the fillet weld bevelled edge, when adopting the primary reflection method of detection, acoustic beam can not be vertical with groove, should adopt secondaries to detect a flaw.When selecting probe, because of the head angle at different detection zones different.Vertical tangent plane of actual detected face will by the infinitely-great ellipse of major axis gradually change into one just round, therefore the mode that all can take roughly to estimate such as location and incident angle is carried out; Take the method for five equilibrium simultaneously, within the specific limits, get a kind of probe with the regional center line selection and detect a flaw, when reducing to adopt a kind of probe, caliber rings the scape of head angle.Because it is much thin that insertion pipe is compared with the person in charge, the weld width changing factor is not considered.

This incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves comprises the steps:

1. sensing range is divided into eight detection zones of three types

Two symmetrical detection zones are set: first detection zone (A1) and the 5th detection zone (A5) on the person in charge's axial surface outside fillet weld, two symmetrical detection zones are set on the person in charge's radial surface outside fillet weld: the 3rd detection zone (A3) and the 7th detection zone (A7), above-mentioned four detection zones are 60 degree sector regions; Four symmetrical detection zones are set between above-mentioned four detection zones: it is fan-shaped that second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8), each detection zone are 30 degree; Thereby circular detection zone is divided into eight detection zones, i.e. A1～A8 district, as shown in Figure 2, probe 4 is placed on the centre position of each detection zone.

2. determine the probe K value

Eight detection zones according to three types calculate its head angle respectively:

(1). first detection zone (A1) and the 5th detection zone (A5)

Undertaken by normal butt-weld technology,, should adopt the probe of 55-60 degree to detect according to groove angle.

(2). the 3rd detection zone (A3) and the 7th detection zone (A7)

Mean value calculation by fillet weld outside groove lower extreme point angle and upper extreme point angle:

Since test surface be one just round, as shown in Figure 3, when incident secondaries acoustic beam is vertical with groove as can be known, get to when going up most point and arriving at the most following, the required incident angle of popping one's head in is to diminish gradually.Because the practical center position not in the center of circle, will be very complicated as the need accurate Calculation.Because insertion pipe is compared caliber with the person in charge and is differed greatly, so, during calculating O and O ' are carried out as a bit, just promptly doing, circle calculates.Computation process is as follows:

When the incident acoustic beam is got to lower extreme point,

$\frac{\cos \mathrm{\γ}}{\sin \mathrm{\α}}=\frac{r}{r+h},$ $\frac{\sin \mathrm{\β}}{\sin \mathrm{\α}}=\frac{r}{R}$

Then can get:

$\frac{\sin \mathrm{\β}}{\cos \mathrm{\γ}}=\frac{r+h}{R}$

Then

$K=\mathrm{tg}\left(\arcsin \left(\frac{r+h}{R}\cos \mathrm{\γ}\right)\right)$

When getting to upper extreme point:

r+h＝R，

Then

K＝tg(arcsin(cosγ))

In above formula and Fig. 3:

O '-the center of circle;

O-practical center (being the intersection point of insertion pipe outer wall and quadrant radius);

γ-groove angle (being known angle);

α-incident ray and incident ray are at the angle of being responsible for inwall reflection spot and O ' line;

β-incident angle (for asking angle in advance);

H-is depth of penetration (be approximately when incident ray is got to upper extreme point and be responsible for wall thickness) not;

R-is responsible for inside radius;

R-is responsible for external radius;

Incident ray when 5-gets to upper extreme point;

Incident ray when 6-gets to lower extreme point;

Therefore, for simplifying the operation, head angle is got the mean value of end points angle up and down.This value should be calculated according to practical work piece and get.

(3). the head angle of second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8)

These four zones are oval along the tangent plane of weld seam vertical direction, the calculating more complicated of head angle, and the present invention carries out the purpose of area dividing exactly in order to simplify the operation, therefore, that pops one's head in when detect a flaw in these several zones chooses, and can adopt following two kinds of schemes; A kind of scheme is to adopt the probe of first detection zone (A1) and the 3rd detection zone (A3) to detect, and another kind of scheme is that the probe of intermediate value of getting the head angle of the head angle of employing first detection zone (A1) and the 3rd detection zone (A3) detects.

(4). when probe is selected, should note calculating the incident acoustic beam and whether can get to and be responsible for inside surface and be split into primary event this condition of detecting a flaw.Therefore, should can get under the condition of being responsible for inside surface formation primary event flaw detection, determine the probe K value at assurance incident acoustic beam;

When probe is selected, be foundation with the ratio of interior external diameter:

$k<\frac{X}{\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="A20081005303200111.png,A20081005303200121.png"\; state="\{\{state\}\}">X</figure-callout>}}^2}}$

Wherein

$X=\frac{r}{R}$

In the formula: r is responsible for inside radius; R is responsible for external radius.

(5) probe wafer and frequency

Because probe carries out carrying out flaw detection on arc surface, therefore probe should use little wafer probe, otherwise is difficult for grasping the surface of contact of incidence point and pipe fitting, and in the present embodiment, wafer is of a size of 9mm * 9mm.In addition,, should not carry out reconditioning, be the heavy wall flaw detection simultaneously, so frequency probe should adopt the 2.5MHz frequency probe because of the detection faces radian constantly changes.

In sum, for the probe in the 3rd detection zone (A3), the lower extreme point K value of popping one's head in as calculated is: K1.159, upper extreme point K value is: K1.73, probe get the mean value of end points up and down, are K1.5.

For the probe in first detection zone (A1),, can select the probe of K1.5 according to groove angle

For the probe in second detection zone (A2), can select the intermediate value of interior probe of first detection zone (A1) and the probe in the 3rd detection zone (A3), therefore also can select the probe of K1.5.

Can get to person in charge's inside surface for assurance incident acoustic beam, X=0.82 then should K＜1.43.

Therefore, present embodiment has been selected the probe of K1.4, and this moment, incident angle was:

Arctg (1.4)=54.5 degree

The incident acoustic beam is basic vertical with the groove plane.Therefore, for ID457 * 50mm, groove is that the plug-in type base of 30-35 degree selects the probe of K1.4 can satisfy the flaw detection requirement.

3. selection test block

Adopt the large-diameter pipe test block (CSK-I B, RB-3) identical with plug-in type base material, the test block material is A335P91;

4. defectoscope selects for use

Select Chinese prestige HS-600a or USM-22 Digital Ultrasonic Flaw Detector for use, the horizontal linearity of instrument satisfies in 100mm sound path scope error should be smaller or equal to ± 0.1%, the time real sample frequency 55～58MHz.

Through the 1st～4 step, determined following carrying out flaw detection parameter and checkout equipment:

Probe K value: K1.4;

Wafer size: 9mm * 9mm;

Frequency probe: 2.5MHz;

Probe forward position: be not more than 10mm;

Test block: large-diameter pipe test block (CSK-I B, RB-3);

Test block material: A335P91;

Defectoscope: digital ultrasonic flaw detectors such as HS600 series or USM-22.

Below insertion pipe seat fillet weld ultrasound examination parameter setting and checkout procedure are described:

5. defectoscope is regulated

With A335P91 material large-diameter pipe test block (CSK-I B, RB-3), measure probe forward position, K value, scanning ratio, because main detected object is the groove incomplete fusion, and be similar to the steel pipe detection.For for simplicity, with reference to the JB/T4730-2005 third part: ultrasound examination " 4.5 bearing devices detect and quality grading with seamless steel pipe supersonic " is apart from amplitude curve with one times with twice wall thickness degree of depth artificial defect hole echo 60% height line; With twice wall thickness degree of depth hole reflection echo 60%, and improve 6dB as Scanning sensitivity.

6. defect location

On the person in charge of fillet weld periphery, draw the probe moving area 9, its method is as follows:

(1). calculate the upper and lower end points horizontal level and the corresponding arc length of interior probe positions of first detection zone (A1) and the interior probe positions of the 3rd detection zone (A3) respectively; From the interior probe positions of interior probe positions to the three detection zones of detection zone first detection zone (A1) (A3), when incident acoustic wave is got to same position, the horizontal range of probe 1 shows minimum in first detection zone (A1), the horizontal range of the interior probe positions 3 of the 3rd detection zone (A3) shows maximum, can think that then other probe positions level is presented between the two.Therefore calculate two probe positions upper extreme points 7, the demonstration of lower extreme point 8 levels and corresponding arc length respectively.

(2). according to the pairing arc length value of upper and lower end points of the probe positions of the probe positions of first detection zone (A1) that calculates and the 3rd detection zone (A3), and on the plug-in type base, draw and be the probe moving area along two zones that line surrounded of weld seam trend.

Then, use probe to detect a flaw, when probe positions is coincide in the relevant position of maximum and minimum value substantially with the echo level distance, promptly be judged to be incomplete fusion at the probe moving area.

Can realize incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves by above-mentioned steps.The concrete application has the following example:

(1). use the detection of this method to road weld bond surplus the same specification 60 of three power plant, find groove incomplete fusion defective 17 roads altogether, other is bigger declares useless defective, road surplus pore, the slag inclusion etc. 20, all defect has all passed through on-the-spot dissection checking.We can say, adopt said method, ID457 * 50mm and φ 38 * 7mm pressure base are carried out ultrasound examination, can detect the defective of groove incomplete fusion accurately and effectively, guarantee the weld bond quality preferably.

(2). use this method that the base fillet weld of certain southern power plant is detected, detect road (wherein specification has been not limited to ID457 * 50mm and φ 38 * 7mm pressure base) surplus the weld bond 300 altogether, detect incomplete fusion 37 roads, crackle 11 roads, and the tens of roads of other excessive defect, sound assurance the safe operation in power station.

Though being the defective at plug-in type base fillet weld incomplete fusion, the present invention detects, in fact, effective equally to the otherwise detection of fillet weld, for other defect with reference to the JB/T4730-2005 third part: ultrasound examination " 4.5 bearing devices detect and quality grading with seamless steel pipe supersonic ", declaring when hindering, when echo more than or equal to artificial reflecting body benchmark wave height, promptly be judged to be defective.

It is emphasized that; embodiment of the present invention is illustrative; rather than it is determinate; therefore the present invention is not limited to the embodiment described in the embodiment; every other embodiments that draw by those skilled in the art's technical scheme according to the present invention; as use this method to detect the other defect of plug-in type base fillet weld, belong to the scope of protection of the invention equally.

Claims (6)

1. incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves, it is characterized in that: this method comprises the steps:

(1). sensing range is divided into eight detection zones of three types: the charge shaft outside fillet weld is to lip-deep two symmetrical detection zones: first detection zone (A1) and the 5th detection zone (A5), main drive tube outside fillet weld is to lip-deep two symmetrical detection zones: four symmetrical detection zones between the 3rd detection zone (A3) and the 7th detection zone (A7) and above-mentioned four detection zones: second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8);

(2). determine the probe K value: calculate the head angle of three types of detection zones respectively,, can get under the condition of being responsible for inside surface formation primary event flaw detection, determine the probe K value at assurance incident acoustic beam according to probe wafer and frequency;

(3). select test block: adopt the large-diameter pipe test block identical with plug-in type base material, the test block material is A335P91;

(4). select defectoscope: adopt Chinese prestige HS-600a or USM-22 Digital Ultrasonic Flaw Detector;

(5). defectoscope is regulated: with one times be apart from amplitude curve with twice wall thickness degree of depth artificial defect hole echo 60% height line, with twice wall thickness degree of depth hole reflection echo 60%, and raising 6dB is as Scanning sensitivity;

(6). defect location: the probe moving area that on the person in charge of fillet weld periphery, draws, use probe to detect a flaw at the probe moving area, when probe positions is coincide in the relevant position of maximum and minimum value substantially with the echo level distance, promptly be judged to be incomplete fusion.

2. incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves according to claim 1, it is characterized in that: described first detection zone (A1), the 5th detection zone (A5), the 3rd detection zone (A3) and the 7th detection zone (A7) are the sector region of 60 degree, and described second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8) are the sector region of 30 degree.

3. incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves according to claim 1 is characterized in that: the person in charge at described plug-in type base angle is that ID457 * 50mm, arm are that φ 38 * 7mm and groove are temperature, the pressure base of 30-35 degree.

4. incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves according to claim 1 is characterized in that: the method for the head angle of described definite three types of detection zones is:

(1). first detection zone (A1) and the 5th detection zone (A5) according to groove angle, adopt the probe of 55-60 degree by normal butt-weld technology Calculation head angle;

(2). the 3rd detection zone (A3) and the 7th detection zone (A7) are by the mean value calculation of fillet weld outside groove lower extreme point angle and upper extreme point angle;

(3). the head angle of second detection zone (A2), the 4th detection zone (A4), the 6th detection zone (A6) and the 8th detection zone (A8) adopts the head angle of first detection zone (A1) and the 3rd detection zone (A3) or adopts the head angle of first detection zone (A1) and the intermediate value of the head angle of the 3rd detection zone (A3).

5. incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves according to claim 1 is characterized in that: described probe wafer is 9mm * 9mm wafer, and its frequency is the 2.5MHz frequency.

6. incomplete-fusion ultrasonic detection method for plug-in type pipe socket angle weld grooves according to claim 1 is characterized in that: described method of drawing the probe moving area on the person in charge of fillet weld periphery is:

(1). calculate the upper and lower end points horizontal level and the corresponding arc length of interior probe positions of first detection zone (A1) and the interior probe positions of the 3rd detection zone (A3) respectively;

(2). according to the pairing arc length value of upper and lower end points of the probe positions of the probe positions of first detection zone (A1) that calculates and the 3rd detection zone (A3), and on the plug-in type base, draw and be the probe moving area along two zones that line surrounded of weld seam trend.

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