CN103542819A - Detection and quality judgment method for strip steel weld surface appearance - Google Patents

Abstract

Disclosed is a detection and quality judgment method for strip steel weld surface appearance. The surface of a weld is scanned by a linear laser; the values such as weld stack height, depression, undercut and misalignment are calculated according to scanned data; the quality of the weld is judged according to the values; accordingly, the surface appearance quality of the weld is judged continuously. The method has the advantages that the surface appearance of the weld can be detected fast and evaluated fast, fast continuous operation of an acid tandem rolling is ensured, and breakage of strip steel is prevented.

Description

A kind of detection and quality judging method with steel face of weld pattern

Technical field

The present invention relates to belt steel surface detection technique, particularly a kind of detection and quality judging method with steel face of weld pattern.

Background technology

Quality with steel weld seam is judged by on-the-spot operative employee's naked eyes conventionally at present, and this method of discrimination obviously exists operating personnel's experience and the defect on discrimination standard, has the problem that efficiency is low and differentiation is inaccurate.

The QCDS system that Miebach company releases can realize the automatic detection of weld seam pattern, this system adopts online CCD video observing to survey the weld seam pattern of belt steel surface, can provide in time the shape appearance figure of face of weld, and the curve that provides welding depression and misalignment judges the quality of weld seam for operating personnel, the real-time online of realizing face of weld pattern detects, but this system cannot judge the undercut defect that has a strong impact on the anti-fracture energy of weld seam, also Shortcomings on discrimination standard.

Chinese Patent Application No. 200810229989 discloses " a kind of face of weld quality vision sensor based on line-structured light ", utilize this sensor can obtain the pattern of face of weld, but the design parameter of this patent not mentioned Linear Laser device, the frequency particularly scanning, and the technology that this patent is mentioned does not have the analytic function to test result.

Summary of the invention

The object of the present invention is to provide a kind of detection and quality judging method with steel face of weld pattern, fast detecting is to the pattern of face of weld, and evaluate fast, guarantee moving continuously and fast of pickling and cold-rolled process, prevent the generation with steel broken belt accident.

For achieving the above object, technical scheme of the present invention is:

The present invention adopts scanning of Linear Laser device butt welded seam surface, according to the resulting data of scanning, draw out the surface topography map of weld seam, simultaneously according to resulting scan-data, the numerical value such as weld seam heap is high by calculating, depression, undercut, misalignment, according to the surface topography quality of this numerical value butt welded seam, differentiate, thereby realize the continuous judge of butt welded seam surface topography quality.

In sour milling train group, for guaranteeing the continuous operation of milling train, move ahead and need to adopt together with the method for welding connects with steel and rear row band steel, the welding quality of weld seam is to guarantee that weld seam can be smoothly by the condition precedent of milling train, weld defects in welding will directly cause weld seam at straightening and milling train Fracture, form broken belt accident.With steel weld seam before entering into milling train by the alternating bending of bearing repeatedly, in the process of alternating bending, stress concentration portion position in weld seam can produce fatigue crack, the generation of these crackles will directly reduce the intensity of weld seam, affects face of weld stress and concentrates the weld seam pattern defect of the order of severity to have: weld seam heap is high, welding depression, undercut and welding seam misalignment.

Particularly, a kind of detection and quality judging method with steel face of weld pattern of the present invention, adopt the scanning of Linear Laser device to detect in real time the topographic data of face of weld, comprise that weld seam heap is high, depression, undercut, overlap joint, calculate above-mentioned characteristics of weld seam value, the maximum position of statistical characteristics and section feature, set up weld seam pattern evaluation criterion, detect in real time again the pattern of face of weld, obtain the eigenwert of face of weld pattern, compare with weld seam pattern evaluation criterion, thereby realize the judgement of face of weld quality; Wherein:

A) pile high

Weld seam heap is high represents that weld seam is higher than the numerical value of mother metal, and the computing formula of heap high equivalent weight area is:

$\mathrm{<figure-callout\; id="1"\; label="A"\; filenames="120717091415.png"\; state="\{\{state\}\}">A</figure-callout>}1=\underset{i=1}{\overset{\mathrm{TT}}{\mathrm{\&Sigma;}}}{h}_1\left(i\right)\&times;\frac{60\&times;u}{\mathrm{<figure-callout\; id="2"\; label="H\; mm"\; filenames="120717091415.png"\; state="\{\{state\}\}">H</figure-callout>}}{\mathrm{mm}}^{}{}^2$

In formula: h ₁(i) be the high value of heap of the i time scanning the data obtained, mm; H is the frequency of laser scans scanning, Hz, and u is speed of welding, mm/s, TT is the scanning times of whole piece weld seam;

The heap height of weld seam can make commissure produce stress to concentrate, and the impact of piling high butt welded seam intensity represents with piling high coefficient, and the computing formula of piling high coefficient is:

${\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="120717091415.png"\; state="\{\{state\}\}">f</figure-callout>}}_1=1+\frac{3\&times;h_1\left(i\right)}{t}$

In formula: h ₁(i) be the high value of heap of the i time scanning the data obtained, t is the thickness with steel, mm;

B) overlap joint

Overlap joint refers to the unfitness of butt joint of weld seam two sideband steel, and the computing formula of overlap joint equivalent aera is:

$\mathrm{<figure-callout\; id="2"\; label="A"\; filenames="120717091415.png"\; state="\{\{state\}\}">A</figure-callout>}2=\underset{i=1}{\overset{\mathrm{TT}}{\mathrm{\&Sigma;}}}{h}_2\left(i\right)\&times;\frac{60\&times;u}{\mathrm{<figure-callout\; id="2"\; label="H\; mm"\; filenames="120717091415.png"\; state="\{\{state\}\}">H</figure-callout>}}{\mathrm{mm}}^{}{}^2$

In formula: h ₂(i) be the overlap joint value of the i time scanning the data obtained of weld seam, mm; H is the frequency of scanning, Hz; U is speed of welding, mm/s;

The overlap joint of weld seam can make commissure produce stress to concentrate, and the impact of overlap joint butt welded seam intensity represents with overlapping fraction, and the computing formula of overlapping fraction is:

${\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="120717091415.png"\; state="\{\{state\}\}">f</figure-callout>}}_2=1+\frac{5\&times;h_2\left(i\right)}{t}$

In formula: h ₂(i) be the overlap joint value of i root bead seam section line centerline, mm; T is the thickness with steel, mm;

C) depression

Welding depression refers to that the height of welded seam area is lower than the height value with steel mother metal, consider that the overlap joint of weld seam is by the concentrated order of severity of the stress of deepening depression position, therefore when calculating depression equivalent aera, overlapping fraction is taken into account, the computing formula of notch area is:

$A3=\underset{i=1}{\overset{\mathrm{<figure-callout\; id="2"\; label="TT\; f"\; filenames="120717091415.png"\; state="\{\{state\}\}">TT</figure-callout>}}{\mathrm{\&Sigma;}}}{f}_{}{}_2\&times;h_3\left(i\right)\&times;\frac{60\&times;u}{H}{\mathrm{mm}}^2$

H ₃(i) be the depression value of the i time scanning the data obtained, mm; H is the frequency of scanning, Hz; U is speed of welding, mm/s;

D) undercut

Undercut refers to that minimum point within the scope of the 1mm of weld-fusion line left and right is as undercut value, weld seam heap height and the overlap joint of considering undercut position will increase the weight of the concentrated order of severity of undercut position stress simultaneously, therefore when calculating undercut area, heap height and overlapping fraction are taken into account, the equivalent aera computing formula of total undercut amount is:

$A4=\underset{i=1}{\overset{\mathrm{<figure-callout\; id="1"\; label="TT\; f"\; filenames="120717091415.png"\; state="\{\{state\}\}">TT</figure-callout>}}{\mathrm{\&Sigma;}}}{f}_{}{}_1\&times;{\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="120717091415.png"\; state="\{\{state\}\}">f</figure-callout>}}_2\&times;h_3\left(i\right)\&times;\frac{60\&times;u}{H}{\mathrm{mm}}^2;$

Weld seam pattern evaluation criterion:

Sequence number	Index name	Threshold value	Judged result, as exceed threshold value
				1	Pile high maximal value (h1)	0.2～0.4	There is high the exceeding standard of heap in weld seam regional area
2	Depression maximal value (h2)	0.2～0.4	Weld seam regional area exists depression to exceed standard
				3	Undercut maximal value (h3)	0.2～0.4	Weld seam regional area exists overlap joint to exceed standard
4	Overlap joint maximal value (h4)	0.2～0.4	Weld seam regional area exists undercut to exceed standard
				5	Heap high equivalent weight value (A1/A)	0.05～0.2	Weld seam heap is high excessive
6	Depression equivalent value (A2/A)	0.05～0.2	Cave in excessive
				7	Undercut equivalent value (A3/A)	0.05～0.2	Undercut is excessive
8	Overlap joint equivalent value (A4/A)	0.05～0.2	Overlap excessive
				9	Comprehensive evaluation (A3/A+A4/A)	0.1～0.4	There are serious problems in weld seam

Further, the scanning of Linear Laser device butt welded seam pattern, sweep length scope is at 3～10mm, height detection scope is at 50～150mm, accuracy of detection is at 0.001～0.005mm, and the data that detect send in upper industrial computer in real time, and sweep frequency is not less than 30Hz.

Again, the present invention adopts and comprises Linear Laser device, trigger switch, upper industrial computer, the next PC, and Linear Laser device, trigger switch, upper industrial computer are fixed on welding machine, in testing process, with welding machine, move; Upper industrial computer is responsible for the acquisition and processing of signal, the data that Linear Laser device is collected are filtered, collect the data within the scope of weld seam and weld seam two limit 3mm, these data are sent to the next PC by Ethernet, by the next PC butt welded seam, detect data analysis; Trigger switch is for controlling the startup of line style laser instrument and stopping, when trigger switch detects the edge with steel, Linear Laser device is started working and is sent continuously detection data to upper industrial computer, after welding machine finishes, trigger switch detects welding machine and leaves after band steel, trigger switch notifies upper industrial computer to close line style laser instrument, and laser instrument quits work, and the signal that trigger switch sends is pulse signal.

The next PC is born the analyzing and processing work that butt welded seam detects data.

Beneficial effect of the present invention

The inventive method can effectively detect face of weld pattern defect, analytic function powerful in evaluation system can be evaluated in time according to testing result the quality of weld seam, for the weld seam that has excessive defect, provide real-time prompting, this system has important effect to preventing with the broken belt of steel weld seam.

Accompanying drawing explanation

Fig. 1 is the high schematic diagram of weld seam pattern defect of the present invention-pile.

Fig. 2 is the schematic diagram of weld seam pattern defect-depression of the present invention.

Fig. 3 is the schematic diagram of weld seam pattern of the present invention defect-undercut.

Fig. 4 is the schematic diagram of weld seam pattern defect-overlap joint of the present invention.

Fig. 5 is the schematic diagram of system embodiment of the present invention.

Embodiment

Below in conjunction with embodiment, the present invention will be further described.

Referring to Fig. 1 ~ Fig. 5, the present invention adopts scanning of Linear Laser device butt welded seam surface, according to the resulting data of surface topography of scanning weld seam, the numerical value such as weld seam heap is high by calculating, depression, undercut, misalignment, according to the surface topography quality of this numerical value butt welded seam, differentiate, thereby realize the continuous judge of butt welded seam surface topography quality.

Referring to Fig. 5, detection and the quality judging method of band steel face of weld pattern of the present invention, adopt and comprise Linear Laser device 1, trigger switch 2, upper industrial computer 3, the next PC 4, Linear Laser device, trigger switch, industrial computer are fixed on welding machine, in testing process, with welding machine, move; Upper industrial computer is responsible for the acquisition and processing of signal, the data that Linear Laser device is collected are filtered, collect the data within the scope of weld seam and weld seam two limit 3mm, these data are sent to the next PC by Ethernet, by the next PC butt welded seam, detect data analysis; Trigger switch is for controlling the startup of line style laser instrument and stopping, when trigger switch detects the edge with steel 5, Linear Laser device is started working and is sent continuously detection data to upper industrial computer, after welding machine finishes, trigger switch detects welding machine and leaves after band steel, trigger switch notifies upper industrial computer to close line style laser instrument, and laser instrument quits work, and the signal that trigger switch sends is pulse signal.

Embodiment 1

The operation of rolling of cold rolling production line Automobile Plate.

1) this weld inspection system is comprised of laser instrument, trigger switch, upper industrial computer and the next PC, laser instrument, trigger switch, upper industrial computer are fixed on welding machine, in testing process, with welding machine, move, the next PC is placed on operation room, and weld seam evaluating system is installed in slave computer.

2) Linear Laser device adopts the CC3000-30 of U.S. Bytewise company to complete the scanning of butt welded seam pattern, sweep length scope 10mm, height detection scope is at 30mm, and accuracy of detection is at 0.015mm, the data that detect send in upper industrial computer in real time, and detection frequency is 30HZ.Upper industrial computer is responsible for the acquisition and processing of signal, the data that laser instrument is collected are filtered, the common 10mm of collection weld seam and weld seam both sides 3mm() data in scope, send to the next PC by these data by Ethernet, have the next PC butt welded seam to detect data analysis.

3) trigger switch adopts NPN often to close model, model ES12-D15C1, when trigger switch detects the edge with steel, laser instrument is started working and is sent continuously detection data to upper industrial computer, after welding machine finishes, trigger switch detects welding machine and leaves after band steel, and trigger switch notifies upper industrial computer to close laser instrument, and laser instrument quits work.

4) the next PC receives after the data of pick-up unit transmission, can show that weld seam pattern shows, calculates calculating, statistical characteristics maximum position and the section feature of characteristics of weld seam value (piling high, depression, undercut, overlap joint), provides weldquality evaluation result function, all data that detect remain in system.

5) the next PC detects after weld seam signal, calculates the eigenwert of weld seam, and overall judgment criteria is in Table 1.

Table 1 is for the evaluation index of Automobile Plate

Sequence number

Index name

Threshold value

Judged result, as be greater than threshold value

1	Pile high maximal value (h1)	0.4	There is high the exceeding standard of heap in weld seam regional area "
				2	Depression maximal value (h2)	0.4	Weld seam regional area exists depression to exceed standard
3	Undercut maximal value (h3)	0.4	Weld seam regional area exists overlap joint to exceed standard
				4	Overlap joint maximal value (h4)	0.4	Weld seam regional area exists undercut to exceed standard
5	Heap high equivalent weight value (A1/A)	0.2	Weld seam heap is high excessive
				6	Depression equivalent value (A2/A)	0.2	Cave in excessive
7	Undercut equivalent value (A3/A)	0.2	Undercut is excessive
				8	Overlap joint equivalent value (A4/A)	0.2	Overlap excessive
9	Comprehensive evaluation (A3/A+A4/A)	0.4	There are serious problems in weld seam

6) adopt the control index of table 1, Automobile Plate weld seam is carried out to detecting and assessing, for the good weld seam of weldquality, judged result is qualified ".For face of weld, exist the weld seam detection judged result of serious quality problems defective; From testing result, this weld seam is bad central panel shape, and limit portion has obvious depression, judgment result is that defective, but this evaluation result does not cause welder's attention, after clearance, at the 2nd frame generation broken belt of milling train, broken belt just in time occurs in the limit portion that has significant depressions.

Embodiment 2

The composition of system is identical with embodiment 1, for low grade silicon steel, because the fragility of material is very large, need to adjust evaluation index, and the index after adjustment is in Table 2.Adopt this index to carry out the evaluation of low grade silicon steel weld seam, broken belt rate can be controlled at below 1 ‰.

Table 2 is for the evaluation index of low grade silicon steel

Sequence number	Index name	Threshold value	Judged result, as be greater than threshold value, judge
				1	Pile high maximal value (h1)	0.3	There is high the exceeding standard of heap in weld seam regional area "
2	Depression maximal value (h2)	0.3	Weld seam regional area exists depression to exceed standard
				3	Undercut maximal value (h3)	0.3	Weld seam regional area exists overlap joint to exceed standard
4	Overlap joint maximal value (h4)	0.3	Weld seam regional area exists undercut to exceed standard
				5	Heap high equivalent weight value (A1/A)	0.2	Weld seam heap is high excessive
6	Depression equivalent value (A2/A)	0.15	Cave in excessive
				7	Undercut equivalent value (A3/A)	0.15	Undercut is excessive
8	Overlap joint equivalent value (A4/A)	0.15	Overlap excessive
				9	Comprehensive evaluation (A3/A+A4/A)	0.2	There are serious problems in weld seam

Embodiment 3

The composition of system is identical with embodiment 1, and for middle grade silicon steel, because the silicone content in material is higher, the fragility of material is larger, needs the strict defect threshold value that limits, and the index after adjustment is in Table 3.Adopt this index to carry out the evaluation of middle grade silicon steel weld seam, broken belt rate can be controlled at below 1 ‰.

Table 3 is for the evaluation index of low grade silicon steel

Sequence number	Index name	Threshold value	Judged result, as be greater than threshold value, judge
				1	Pile high maximal value (h1)	0.25	There is high the exceeding standard of heap in weld seam regional area "
2	Depression maximal value (h2)	0.20	Weld seam regional area exists depression to exceed standard
				3	Undercut maximal value (h3)	0.20	Weld seam regional area exists overlap joint to exceed standard
4	Overlap joint maximal value (h4)	0.20	Weld seam regional area exists undercut to exceed standard
				5	Heap high equivalent weight value (A1/A)	0.15	Weld seam heap is high excessive
6	Depression equivalent value (A2/A)	0.10	Cave in excessive
				7	Undercut equivalent value (A3/A)	0.10	Undercut is excessive
8	Overlap joint equivalent value (A4/A)	0.10	Overlap excessive
				9	Comprehensive evaluation (A3/A+A4/A)	0.15	There are serious problems in weld seam

Embodiment 4

The composition of system is identical with embodiment 1, and for high grade silicon steel, because the silicone content in material is high, the fragility of material is very large, needs the strict defect threshold value that limits, and the index after adjustment is in Table 4.Adopt this index to carry out the evaluation of high grade silicon steel weld seam, broken belt rate can be controlled at below 1 ‰.

Table 4 is for the evaluation index of low grade silicon steel

Sequence number	Index name	Threshold value	Judged result, as be greater than threshold value, judge
				1	Pile high maximal value (h1)	0.2	There is high the exceeding standard of heap in weld seam regional area "
2	Depression maximal value (h2)	0.2	Weld seam regional area exists depression to exceed standard
				3	Undercut maximal value (h3)	0.2	Weld seam regional area exists overlap joint to exceed standard
4	Overlap joint maximal value (h4)	0.2	Weld seam regional area exists undercut to exceed standard
				5	Heap high equivalent weight value (A1/A)	0.05	Weld seam heap is high excessive
6	Depression equivalent value (A2/A)	0.05	Cave in excessive
				7	Undercut equivalent value (A3/A)	0.05	Undercut is excessive
8	Overlap joint equivalent value (A4/A)	0.05	Overlap excessive
				9	Comprehensive evaluation (A3/A+A4/A)	0.10	There are serious problems in weld seam

Claims (3)

1. detection and quality judging method with a steel face of weld pattern, adopt the scanning of Linear Laser device to detect in real time the topographic data of face of weld, detect that weld seam heap is high, the weld defect of depression, undercut, overlap joint, calculate above-mentioned characteristics of weld seam value, the maximum position of statistical characteristics and section feature, set up weld seam pattern evaluation criterion, detect in real time again the pattern of face of weld, obtain the eigenwert of face of weld pattern, compare with weld seam pattern evaluation criterion; Wherein:

A) pile high

Weld seam heap is high represents that weld seam is higher than the numerical value of mother metal, and the computing formula of heap high equivalent weight area is:

$A1=\underset{i=1}{\overset{\mathrm{TT}}{\mathrm{\&Sigma;}}}{h}_1\left(i\right)\&times;\frac{60\&times;u}{H}{\mathrm{mm}}^2$

In formula: h ₁(i) be the high value of heap of the i time scanning the data obtained, mm; H is the frequency of laser scans scanning, Hz, and u is speed of welding, mm/s, TT is the scanning times of whole piece weld seam;

The computing formula of piling high coefficient is:

$f_1=1+\frac{3\&times;h_1\left(i\right)}{t}$

In formula: h ₁(i) be the high value of heap of the i time scanning the data obtained, mm; T is the thickness with steel, mm;

B) overlap joint

Overlap joint refers to the unfitness of butt joint of weld seam two sideband steel, and the computing formula of overlap joint equivalent aera is:

$A2=\underset{i=1}{\overset{\mathrm{TT}}{\mathrm{\&Sigma;}}}{h}_2\left(i\right)\&times;\frac{60\&times;u}{H}{\mathrm{mm}}^2$

In formula: h ₂(i) be the overlap joint value of the i time scanning the data obtained of weld seam, mm; H is the frequency of scanning, Hz; U is speed of welding, mm/s;

Overlapping fraction:

$f_2=1+\frac{5\&times;h_2\left(i\right)}{t}$

In formula: h ₂(i) be the overlap joint value of i root bead seam section line centerline, mm; T is the thickness with steel, mm;

C) depression

Welding depression refers to that the height of welded seam area is lower than the height value with steel mother metal, consider that the overlap joint of weld seam is by the concentrated order of severity of the stress of deepening depression position, therefore when calculating depression equivalent aera, overlapping fraction is taken into account, the computing formula of notch area is:

$A3=\underset{i=1}{\overset{\mathrm{TT}}{\mathrm{\&Sigma;}}}{f}_2\&times;h_3\left(i\right)\&times;\frac{60\&times;u}{H}{\mathrm{mm}}^2$

H ₃(i) be the depression value of the i time scanning the data obtained, mm; H is the frequency of scanning, Hz; U is speed of welding, mm/s;

D) undercut

Undercut refers to that minimum point within the scope of the 1mm of weld-fusion line left and right is as undercut value, weld seam heap height and the overlap joint of considering undercut position will increase the weight of the concentrated order of severity of undercut position stress simultaneously, therefore when calculating undercut area, heap height and overlapping fraction are taken into account, the equivalent aera computing formula of total undercut amount is:

$A4=\underset{i=1}{\overset{\mathrm{TT}}{\mathrm{\&Sigma;}}}{f}_1\&times;f_2\&times;h_3\left(i\right)\&times;\frac{60\&times;u}{H}{\mathrm{mm}}^2;$

Weld seam pattern evaluation criterion:

Sequence number Index name Threshold value Judged result, as exceed threshold value 1 Pile high maximal value (h1) 0.2～0.4 There is high the exceeding standard of heap in weld seam regional area 2 Depression maximal value (h2) 0.2～0.4 Weld seam regional area exists depression to exceed standard 3 Undercut maximal value (h3) 0.2～0.4 Weld seam regional area exists overlap joint to exceed standard 4 Overlap joint maximal value (h4) 0.2～0.4 Weld seam regional area exists undercut to exceed standard 5 Heap high equivalent weight value (A1/A) 0.05～0.2 Weld seam heap is high excessive 6 Depression equivalent value (A2/A) 0.05～0.2 Cave in excessive 7 Undercut equivalent value (A3/A) 0.05～0.2 Undercut is excessive 8 Overlap joint equivalent value (A4/A) 0.05～0.2 Overlap excessive 9 Comprehensive evaluation (A3/A+A4/A) 0.1～0.4 There are serious problems in weld seam

So far, realize with the detection of steel face of weld pattern and the judgement of quality.

2. detection and quality judging method with steel face of weld pattern as claimed in claim 1, it is characterized in that, the scanning of Linear Laser device butt welded seam pattern, sweep length scope is at 3～10mm, height detection scope is at 50～150mm, accuracy of detection is at 0.001～0.005mm, and the data that detect send in upper industrial computer in real time, and laser scans frequency is not less than 30Hz.

3. detection and quality judging method with steel face of weld pattern as claimed in claim 1, it is characterized in that, employing comprises Linear Laser device, trigger switch, upper industrial computer, the next PC, Linear Laser device, trigger switch, upper industrial computer are fixed on welding machine, in testing process, with welding machine, move; Upper industrial computer is responsible for the acquisition and processing of signal, the data that Linear Laser device is collected are filtered, collect the data within the scope of weld seam and weld seam both sides 3mm, these data are sent to the next PC by Ethernet, by the next PC butt welded seam, detect data analysis; Trigger switch is for controlling the startup of line style laser instrument and stopping, when trigger switch detects the edge with steel, Linear Laser device is started working and is sent continuously detection data to upper industrial computer, after welding machine finishes, trigger switch detects welding machine and leaves after band steel, trigger switch notifies upper industrial computer to close line style laser instrument, and laser instrument quits work, and the signal that trigger switch sends is pulse signal.

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