CN108008012B - Steel structure welding quality defect detection method - Google Patents
Steel structure welding quality defect detection method Download PDFInfo
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- CN108008012B CN108008012B CN201711269343.8A CN201711269343A CN108008012B CN 108008012 B CN108008012 B CN 108008012B CN 201711269343 A CN201711269343 A CN 201711269343A CN 108008012 B CN108008012 B CN 108008012B
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- 238000001514 detection method Methods 0.000 title claims abstract description 125
- 238000003466 welding Methods 0.000 title claims abstract description 116
- 230000007547 defect Effects 0.000 title claims abstract description 52
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 36
- 239000010959 steel Substances 0.000 title claims abstract description 36
- 239000000523 sample Substances 0.000 claims abstract description 76
- 238000000034 method Methods 0.000 claims abstract description 25
- 238000012937 correction Methods 0.000 claims abstract description 9
- 238000012360 testing method Methods 0.000 claims description 11
- 230000002950 deficient Effects 0.000 claims description 10
- 239000013078 crystal Substances 0.000 claims description 8
- 239000002893 slag Substances 0.000 claims description 3
- 238000010276 construction Methods 0.000 description 4
- 238000013461 design Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
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- 230000035515 penetration Effects 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
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- 238000012545 processing Methods 0.000 description 1
- 238000005493 welding type Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/04—Analysing solids
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/26—Scanned objects
- G01N2291/267—Welds
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Abstract
A steel structure welding quality defect detection method divides a welding part into three types of a plane welding line, a cambered surface welding line and a corner welding line, then pulse reflection detection is respectively carried out by utilizing a phased array ultrasonic detection device, a high-frequency probe, a bicrystal probe and a low-frequency probe, phased array ultrasonic primary detection is firstly carried out by utilizing the low-frequency probe when the plane welding line is detected, and secondary detection is carried out by utilizing the high-frequency probe; when the arc surface welding seam is detected, firstly, a low-frequency probe is used for phased array ultrasonic initial detection, and then a bicrystal probe is used for bicrystal phased detection; when the fillet weld is detected, the bicrystal probe is used for carrying out bicrystal phased control detection, and then the low-frequency probe is used for carrying out phased array ultrasonic primary detection. The invention effectively utilizes the difference of stability and accuracy of different probes in different weld detection processes to carry out mutual correction and further refine the result, and has the advantages of low detection cost, strong applicability and accurate detection structure.
Description
Technical Field
The invention relates to a safety detection technology in the field of constructional engineering, in particular to a method for detecting welding quality defects of a steel structure.
Background
With the economic construction entering a rapid development stage, the engineering structure is developing in a direction of being oversize and complicated, the application of the steel structure in the building engineering is more and more extensive, the steel structure adopted in various large stadiums, airports, stations, super high-rise buildings and the like is more and more, and the adoption of high-strength steel with higher strength grade is a necessary trend in the development of the building steel structure. The connecting parts occupy important positions in the steel structure, and the processing, manufacturing and assembling of the steel structure to form the structure are realized by connection. The structure and stress of the connection are complex and often become weak links of the structure, and the quality of the connection directly influences the safety and the service life of the structure.
Generally, the common connection methods of the building steel structure mainly include three types, namely welding, riveting and bolt-nut connection, but mainly adopt welding, so in the welding technology which is a main means for manufacturing and installing the building steel structure, the quality of welding directly influences the construction quality of steel structure engineering. The steel used in the construction steel structure industry is single in variety, few in alloy element variety, low in content and low in strength, the selection requirements of GB 50011-2010 (building earthquake-resistant design Specification) on related steel are specifically stipulated, the construction steel has good weldability and qualified impact toughness, and has good weldability. Since the popularization of the welded steel structure, the damage accident of the existing welded steel structure is continuously generated, one main problem of welding quality is weld joint defects, the weld joint defects refer to defects generated on the surface or the inside of welded metal or steel of a nearby heat affected zone in the welding process, the defects are easily generated in a weld joint and a nearby area, the defects are the places with the largest tensile residual stress in the steel structure, most steel structures are very important bearing stress structures, the effective area of the bearing cross section of the structure is reduced due to the weld joint defects, stress and deformation exist at the same time due to stress concentration generated around the defects, the strength of the welded structure is reduced, the obvious adverse effect is caused on the bearing capacity of the steel structure, and the damage accident can be caused to cause great loss of human bodies and property in severe cases.
Disclosure of Invention
The invention aims to solve the technical problem of providing a method for detecting the welding quality defects of the steel structure, which can be used for detecting a base material and a forming structure as a nondestructive detection method, can detect a surface welding seam and an internal welding seam to find the defects, further ensures the welding quality and is convenient for subsequent maintenance.
The technical problem solved by the invention is realized by adopting the following technical scheme:
a method for detecting welding quality defects of a steel structure comprises the following steps of dividing a welding part into three types including a plane welding line, a cambered surface welding line and a corner welding line according to technical requirements on welding quality of the steel structure in a design drawing, respectively carrying out pulse reflection detection by utilizing phased array ultrasonic detection equipment and a high-frequency probe, a bicrystal probe and a low-frequency probe, and specifically operating the method in the following mode:
the method comprises the following steps of firstly carrying out phased array ultrasonic primary detection on a plane welding seam by using a low-frequency probe by using phased array ultrasonic detection equipment as detection equipment, following the steps of a transverse wave oblique probe flaw detection method during detection, then carrying out secondary detection by using a high-frequency probe, following the steps of a straight probe flaw detection method during detection, simultaneously carrying out detection on defects measured in the primary detection process, finding out the highest echo number of real defects and recording the highest echo number, and comparing the recorded data with the data of a comparison welding test block to obtain the welding defect state of the plane welding seam;
firstly, carrying out phased array ultrasonic initial detection on the arc-surface welding seam by using a low-frequency probe, following the steps of a transverse wave oblique probe flaw detection method during detection, then carrying out bicrystal phased detection by using a bicrystal probe, following the steps of a straight probe flaw detection method during detection, simultaneously detecting the detected defects in the initial detection process, finding and recording the highest echo number of the real defects, and comparing the recorded data with the data of a comparison welding test block to obtain the welding defect state of the arc-surface welding seam;
and performing bicrystal phased detection on the corner weld joint by using a bicrystal probe, wherein the steps of a straight probe flaw detection method are followed during detection, then performing phased array ultrasonic primary detection by using a low-frequency probe, the steps of a transverse wave oblique probe flaw detection method are followed during detection, meanwhile, the defects detected in the primary detection process are detected again, the highest echo number of the real defects is found and recorded, and the recorded data is compared with the data of a comparison welding test block to obtain the welding defect state of the corner weld joint.
In the invention, the comparison welding blocks comprise a group of welding blocks with qualified welding seams and a plurality of groups of welding blocks with different defect welding seams, the welding seams comprise plane welding seams, cambered surface welding seams and corner welding seams, and the defects in the defect welding seams are one of cracked welding seams, slag inclusion welding seams, incomplete penetration welding seams, bubble welding seams and incomplete fusion welding seams.
In the invention, the phased array ultrasonic detection equipment is a phased array ultrasonic detector produced by GE company, the high-frequency probe is a 115-sequence high-frequency straight probe, the twin-crystal probe is a 115-sequence twin-crystal probe, and the low-frequency probe is a 115-sequence low-frequency oblique probe.
According to the transverse wave oblique probe flaw detection method, a sensor is buried between a primary pulse and a bottom pulse, an included angle is formed between ultrasonic waves and dangerous defects of a welding seam by using an oblique probe, signals are amplified through the included angle, the information transmitted by the ultrasonic waves is received by the sensor and then is filtered and fed back to a computer processor, the computer converts the fed-back data into a data waveform, and people know the quality of the welding seam by observing the waveform.
In the invention, in order to correct and improve the detection precision, the planning of grade two grade is carried out when the required steel structure welding quality grade is grade one, and the like is carried out until the quality grade is a three-grade standard.
In the invention, the length of the defective welding seam detected in the initial detection needs to be corrected, and the secondary detection is carried out within the range of the corrected length, wherein the correction rule is that the flaw detection length is increased at the positions of two ends of the defective welding seam, and the increased flaw detection length is 15-20% of the length of the welding seam.
Has the advantages that: the invention utilizes different ultrasonic detection means to carry out nondestructive inspection in the steel structure welding quality detection, has simple and efficient operation, intuitive detection result, low detection cost and strong applicability, greatly improves the detection speed and accuracy, and is convenient for relevant personnel to know whether the welding connection part of the steel structure generates different changes.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
In this embodiment, first, according to the technical requirements on the welding quality of the steel structure in the design drawing, the welding portion is divided into three types, namely a plane welding line, an arc welding line and a corner welding line, and meanwhile, a plurality of groups of comparison welding blocks are prepared for the three types of welding lines, wherein the comparison welding blocks comprise a group of welding blocks with qualified welding lines, the group of welding blocks comprise one welding block with qualified plane welding lines, one welding block with arc welding lines and one welding block with corner welding lines, and the group of welding blocks also comprise one welding block with crack welding lines, slag inclusion welding lines, non-penetration welding lines, one plane welding line with bubble welding lines and non-fusion welding lines, one arc welding line and one welding block with corner.
When the phased array ultrasonic detection device is used for detection, a phased array ultrasonic detector produced by GE company is adopted as the phased array ultrasonic detection device, a high-frequency straight probe with 115 sequences is adopted as a high-frequency probe, a twin-crystal probe with 115 sequences is adopted as a twin-crystal probe, and a low-frequency inclined probe with 115 sequences is adopted as a low-frequency probe.
During detection, the low-frequency probe is firstly used for phased array ultrasonic primary detection of a plane welding seam, the steps of a transverse wave inclined probe flaw detection method are followed during detection, and in order to adjust the detection accuracy, the slope of the adopted low-frequency probe is controlled at K2. And then, after the initial detection is finished, correcting the length of the weld joint of the suspected defect, and performing secondary detection within the range of the correction length, wherein the correction rule is that the flaw detection length is increased at the positions of two ends of the defective weld joint, the increased flaw detection length is 15% of the length of the weld joint, the secondary detection is performed by using a high-frequency probe, the steps of a straight probe flaw detection method are followed during detection, meanwhile, the defect detected in the initial detection process is detected again, the highest return wave number of the real defect is found and recorded, and the recorded data is compared with the comparison welding test block data to obtain the welding defect state of the plane weld joint.
Firstly, using a low-frequency probe to carry out phased array ultrasonic initial detection on the welding line of the cambered surface, following the steps of a transverse wave inclined probe flaw detection method during detection, controlling the slope of the adopted low-frequency probe at K2.2 in order to adjust the detection accuracy, then, after the initial detection is finished, the length of the weld joint of the suspected defect is corrected, and the secondary detection is carried out within the range of the corrected length, the correction rule is that the flaw detection length is increased at the two ends of the defective weld, the increased flaw detection length is 20 percent of the length of the weld, then a twin-crystal probe is utilized to carry out secondary accurate detection of twin-crystal phase control, the steps of a straight probe flaw detection method are followed during detection, and simultaneously, and detecting the defects detected in the initial detection process, finding out and recording the highest echo number of the real defects, and comparing the recorded data with the data of the comparison welding test block to obtain the welding defect state of the arc welding seam.
The method comprises the steps of carrying out bicrystal phased detection on a corner weld by using a bicrystal probe, following the steps of a straight probe flaw detection method during detection, then carrying out weld length correction on a suspected defective weld after primary detection is finished, and carrying out secondary detection within the correction length range, wherein the correction rule is that the flaw detection length is increased at the positions at two ends of the defective weld, the increased flaw detection length is 18% of the weld length, then carrying out phased array ultrasonic primary detection by using a low-frequency probe, following the steps of a transverse wave oblique probe flaw detection method during detection, and controlling the slope of the low-frequency probe to be K1.8 in order to adjust the detection accuracy. And detecting the defects detected in the initial detection process, finding out and recording the highest return wave number of the real defects, and comparing the recorded data with the data of the comparison welding test block to obtain the welding defect state of the fillet weld.
And then merging and recording the data of the three parts, and comparing the data with the test data of the comparison welding block to obtain the health state of the welding line. In the embodiment, in order to improve the detection accuracy and correct the relevant data, the planning of grade two is performed for the required steel structure welding quality grade one, and so on until the quality grade is the three-grade standard.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (6)
1. The method for detecting the welding quality defects of the steel structure is characterized in that a welding part is divided into three types, namely a plane welding line, a cambered surface welding line and a corner welding line, pulse reflection detection is respectively carried out by utilizing phased array ultrasonic detection equipment and a high-frequency probe, a bicrystal probe and a low-frequency probe, and the specific operation mode is as follows:
the method comprises the following steps of firstly carrying out phased array ultrasonic primary detection on a plane welding seam by using a low-frequency probe by using phased array ultrasonic detection equipment as detection equipment, following the steps of a transverse wave oblique probe flaw detection method during detection, then carrying out secondary detection by using a high-frequency probe, following the steps of a straight probe flaw detection method during detection, simultaneously carrying out detection on defects measured in the primary detection process, finding out the highest echo number of real defects and recording the highest echo number, and comparing the recorded data with the data of a comparison welding test block to obtain the welding defect state of the plane welding seam;
firstly, carrying out phased array ultrasonic initial detection on the arc-surface welding seam by using a low-frequency probe, following the steps of a transverse wave oblique probe flaw detection method during detection, then carrying out bicrystal phased detection by using a bicrystal probe, following the steps of a straight probe flaw detection method during detection, simultaneously detecting the detected defects in the initial detection process, finding and recording the highest echo number of the real defects, and comparing the recorded data with the data of a comparison welding test block to obtain the welding defect state of the arc-surface welding seam;
and performing bicrystal phased detection on the corner weld joint by using a bicrystal probe, wherein the steps of a straight probe flaw detection method are followed during detection, then performing phased array ultrasonic primary detection by using a low-frequency probe, the steps of a transverse wave oblique probe flaw detection method are followed during detection, meanwhile, the defects detected in the primary detection process are detected again, the highest echo number of the real defects is found and recorded, and the recorded data is compared with the data of a comparison welding test block to obtain the welding defect state of the corner weld joint.
2. The method of claim 1, wherein the reference weld test blocks include a set of weld blocks with acceptable welds and a plurality of sets of weld blocks with different defective welds, including flat welds, arc welds, and corner welds, and the defect in the defective weld is one of a cracked weld, a slag weld, an unwelded weld, a bubble weld, and an unfused weld.
3. The method for detecting the welding quality defects of the steel structure according to claim 1, wherein the phased array ultrasonic detection equipment is a phased array ultrasonic detector manufactured by GE company, the high-frequency probe is a 115-sequence high-frequency straight probe, the twin-crystal probe is a 115-sequence twin-crystal probe, and the low-frequency probe is a 115-sequence low-frequency inclined probe.
4. The method for detecting the welding quality defect of the steel structure as claimed in claim 1, wherein the slope of the low-frequency probe is controlled to be K1.8-K2.2.
5. The method for detecting the welding quality defect of the steel structure as claimed in claim 1, wherein during detection, the operation is performed by performing a two-level rating plan on the required welding quality of the steel structure with one level, and the like until the quality level is a three-level standard.
6. The method of claim 1, wherein the defective weld detected during the initial detection is corrected in length and detected secondarily within the range of the corrected length, and the correction is performed by increasing the flaw detection length at both ends of the defective weld by 15-20% of the weld length.
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| CN103293224B (en) * | 2013-05-08 | 2015-02-18 | 江苏法尔胜材料分析测试有限公司 | Ultrasonic phased array detection method of steel box beam U-rib angle welding seam |
| CN103245729B (en) * | 2013-05-14 | 2015-04-08 | 江苏大学 | Detection method and device for internal defects of welding seams |
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Address after: 410000 No. 101, No. 3 workshop, A District, No. 169, Jin Zhi Yuan, industrial zone, 169 hi Chi Road, hi tech Development Zone, Hunan. Patentee after: Hunan Xiangjian Zhike Engineering Technology Co.,Ltd. Address before: 410000 No. 101, No. 3 workshop, A District, No. 169, Jin Zhi Yuan, industrial zone, 169 hi Chi Road, hi tech Development Zone, Hunan. Patentee before: HUNAN XIANGJIAN DETECTION Co.,Ltd. |
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Denomination of invention: A method for detecting welding quality defects in steel structures Granted publication date: 20200417 Pledgee: Agricultural Bank of China Limited Changsha Wangcheng District sub branch Pledgor: Hunan Xiangjian Zhike Engineering Technology Co.,Ltd. Registration number: Y2024980004640 |
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