CN103115963A - Method for detecting welding seam of resistance weld pipe through creeping wave and creeping wave probe for method - Google Patents
Method for detecting welding seam of resistance weld pipe through creeping wave and creeping wave probe for method Download PDFInfo
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Abstract
The invention discloses a method for detecting a welding seam of a resistance weld pipe through a creeping wave and a creeping wave probe for the method. The method comprises the following steps of: S100, selecting the specification of the creeping wave probe according to the curvature of the resistance weld pipe; S200, regulating the ratio of the sound path and depth of a reflected wave to 2:1; S300, selecting a reference point as the first point of a DAC curve, sequentially determining points at an interval of 5mm to the first point, measuring the amplitude of the reflected wave, drawing a distance-wave amplitude curve according to a measurement result, and attenuating the DAC curve by 10 dB as an evaluation line; S400, placing the sound beam center line of the creeping wave probe on a detection surface in such a way that the sound beam center line of the creeping wave probe is perpendicular to the center of the welding seam, and scanning the part, which is 20-25 mm far away from the center of the welding seam, of one side of the welding seam, wherein the scanning speed of the creeping wave probe is not more than 50mm/s; and S500, comparing a detection result obtained from the step S400 with the evaluation line. The creeping wave probe is a twin-lamella parallel creeping wave probe. The method disclosed by the invention can be used for accurately detecting the defects of the welding seam.
Description
Technical field
The present invention relates to a kind of weld inspection method and dedicated probe thereof.
Background technology
Huainan～Shanghai 1000kV transmission line of electricity i.e. " Wan Diandong send engineering " is the common-tower double-return UHV transmission line that China's article one adopts steel tube tower completely.Steel tube tower has that the structure power transmission is clear, steel using amount is few, floor area is little, tower is attractive in appearance and the advantage such as additional load is little, is conducive to give full play to the load-bearing capacity of material, improves the transmission line construction level.The form that steel tube tower adopts longitudinal welded pipe to be connected with hubbed flange jam welding, used longitudinal welded pipe requires the following specification of diameter 426mm to adopt the ratio-frequency welding explained hereafter, therefore, the thin-walled alternating-current resistance welded tube of a large amount of thickness between 4mm-8mm arranged (in general in the steel tube tower, wall thickness/caliber less than 0.02 be thin-wall steel tube), 100% ultrasonic testing of engine request high-frequency resistance straight weld pipe, welded tube do not allow to repair.Therefore the steel pipe seam quality is directly connected to safe operation, the circuit reliability of operation of steel tube tower.
The alternating-current resistance welded tube be with hot-rolled coil through after the forming machine moulding, utilize kelvin effect and the proximity effect of high-frequency current, make the fusing of pipe edge heating, under the effect of compression roller, carry out Pressure Welding and fetch and realize producing.The moulding process of resistance weld pipe does not add any welding material in welding process, appearance of weld is not through the over hot melting state, and just weld metal is through recrystallization process, so the chemical analysis of the weld seam that forms and mother metal is in full accord.Therefore the defective that is prone in the resistance weld pipe weld seam is incomplete fusion (cold welding), crackle, be mingled with etc., is mainly the area-type defective of extending along weld seam, because pore, slag inclusion equal-volume type defective generally can not appear in welding technology in the weld seam.
Characteristics according to producing weld defects generally are not suitable for the detection of resistance weld seam to the ray detection method of volume type defects detection sensitivity.Electricity east, Anhui send engineering regulation resistance weld seam detection in Q/GDW384 " steel tube tower in electric transmission line process technology rules " should use the ultrasonic detection method the most effective to the area-type defective, that sensitivity is the highest.For the weld seam of wall thickness more than or equal to 8mm, can carry out ultrasound examination according to the GB/T11345 standard, but at present for thickness less than the ultrasound examination of the welding seam in welded thin-wall pipe of 8mm applicable method without comparison also.When adopting conventional shear wave to detect, because caliber is little, curvature is large, and probe is that line contacts with steel tube surface, and coupling effect is relatively poor, if probe is processed into curved surface, causes reflecting the increase of clutter, also can affect the defect detection effect; It is wide larger that the combination of probe and ultrasonic instrument has determined that initial pulse accounts for, and causes the part pipe thickness to be included in the clutter, makes to declare to be difficult to identification when hindering; Because the K value probe (generally selecting K3) that the general employing of thin-walled is larger, to avoid the near field region to detect, but the surface wave that the ripple of the couplant that exists at any time generation and K3 probe can't be eliminated all can drop near the defect waves position that needs to judge, and without effective removal way, therefore wound is declared in impact.
Summary of the invention
The deficiency that the present invention exists in order to overcome prior art provides a kind of resistance weld pipe weld seam creeping wave testing method that can detect comparatively accurately the defective of weld seam, and a kind of creeping wave probe that is exclusively used in the method is provided simultaneously.
The present invention is achieved by the following technical solutions: a kind of resistance weld pipe weld seam creeping wave testing method, comprise supersonic reflectoscope, creeping wave probe, and the method comprises:
Step S100 selects the creeping wave probe specification according to resistance weld pipe curvature;
Step S200, accommodation reflex wave sound journey and depth ratio are 2:1;
Step S300 chooses reference point, and as the first point of DAC curve, interval 5mm gets any to returning the first point successively, measures simultaneously the reflection wave amplitude, draws distance-amplitude curve according to measurement result, and DAC curve decay 10dB is the evaluation line;
Step S400 is placed on the acoustic beam center line of creeping wave probe on the detection faces perpendicular to the weld seam center, carries out scanning in weld seam one side apart from 20～25mm place, weld seam center, and the Scanning speed of probe is no more than 50mm/s;
Step S500 compares the result of detection of step S400 and evaluation line.
Preferably, step S400 is placed on the acoustic beam center line of creeping wave probe on the detection faces perpendicular to the weld seam center, carries out scanning in weld seam one side apart from 20mm place, weld seam center, and the Scanning speed of probe is 20～50mm/s.
Because the defective that the resistance weld seam produces mainly is the longitudinal defect that extends along weld seam, during ultrasound examination the sound wave incident direction should be as far as possible perpendicular to the direction of defective, tower is thinner with longitudinal resistance welded pipe weld seam wall thickness, can adopt and climb the ripple detection, and this detection method has following advantage:
1, probe can be realized by one-sided detection the detection in the whole cross section of butt welded seam on distance weld seam certain distance;
2, the defect risks such as the incomplete fusion (cold welding) in incident acoustic beam and the weld seam, crackle are substantially vertical, and detection sensitivity is high;
3, because climbing ripple crosses whole welding joint, so testing process is the straight line scanning, but not the sawtooth pattern scanning is easy to operate, thereby has alleviated scanning workload, high efficiency.
In second aspect, the invention provides a kind of creeping wave probe that is exclusively used in the method, described creeping wave probe is twin lamella block form creeping wave probe.
Preferably, the chip area of described creeping wave probe is not more than 50mm2, and arbitrary length of side is not more than 8mm, and the beam axis offset angle of described creeping wave probe is not more than 2 °.
This creeping wave probe precision is high, good stability, satisfies testing requirement.
Description of drawings
Fig. 1 is creeping wave probe sound field synoptic diagram;
Fig. 2 is for climbing ripple directional property figure;
Fig. 3 is vertical near field and far field synoptic diagram of climbing ripple;
Fig. 4 is entrant sound wedge figure;
Fig. 5 is that the resistance weld pipe weld seam is climbed ripple detection reference block synoptic diagram;
Fig. 6 is that the resistance weld seam is climbed the pitch of waves from-amplitude curve;
Fig. 7 is typical twin crystal creeping wave probe distance-amplitude curve;
Fig. 8 is that thin-walled alternating-current resistance weld seam is climbed ripple detection scanning mode synoptic diagram.
Embodiment
Below in conjunction with accompanying drawing the present invention is described in detail.
Climb ripple and be called again the lower compressional wave in surface, be to approach the compressional wave that propagate on the surface, can survey the defective on nearly surface, the roughness of effects on surface is insensitive, incident angle is arranged near the probe of first critical angle (organic glass) can climb ripple in the steel generation, and this probe is called as creeping wave probe.Creeping wave probe sound field synoptic diagram is seen Fig. 1, and the sound field that creeping wave probe excites has the feature of multimode, has also produced about 33 ° shear wave and bow wave when ripple is climbed in generation.Under the fixed condition of probe, climb ripple and shear wave and be near the incidence point to extraradial; And bow wave is for satisfying free boundary condition, the shear wave that constantly gives off in the process that compressional wave is propagated along the surface.Under the fixed condition of probe, the radiant of bow wave is unfixed, is constantly from climbing the ripple loca to extraradial in climbing the ripple communication process.Fig. 2 is the sound field directive property that creeping wave probe excites, and can find out, at measuring condition (air/steel interface), the refraction angle of climbing the ripple main lobe is about 76 °.
Climb ripple and can think the lower compressional wave in surface, its velocity of propagation is identical with compressional wave.As shown in Figure 3, according to the Snell refraction law, the transducer that incident angle equals first critical angle can produce climbs ripple, also follows simultaneously wide-angle main beam compressional wave.Therefore to the thin-walled weld seam detection, utilize be present in the surface climb the ripple detection of vertical in the defective of face of weld, it is feasible utilizing the main beam compressional wave to detect weld seam defective inner and inside surface.For steel, the main lobe experimental formula is:
This formula shows, wafer is larger, and the main lobe angle is larger, and is only effective to defective in distance case depth 1mm～9mm owing to climbing ripple, therefore can determine its responsive degree of depth on weld seam wall thickness direction by reasonable adjustment wafer size, improve the detection sensitivity of inner and defect in inner surface.
Creeping wave probe can be divided into two classes on structure, one class is the twin lamella tandem, and another kind of is the twin lamella block form, because the wafer tandem has limited the application of large-sized wafer to a certain extent, be not suitable for placing longer wafer, mainly consider the block form structure for thin-walled resistance weld seam.The block form creeping wave probe that uses at present is mainly used in the detection of flat work pieces, can cause on the two plates acoustic beam point of crossing and moves if simply this kind probe is ground into the cambered surface that is complementary with welded tube curvature, and the curvature of cylindrical surface is larger, and effect is more obvious.Therefore to be applied in the detection of path welded tube welding seam climbing ripple, need according to the external diameter of welded tube the structure of probe to be carried out special design.
According to the radius-of-curvature of different welded tubes, the shape of the probe organic glass wedge of design is seen Fig. 4 (wherein label 1 is wafer, and label 2 be sound insulating layer), selects the best according to the radius-of-curvature of welded tube
,
And γ, to realize the high-sensitivity detection of welding seam in welded thin-wall pipe.
Wherein, the computing formula of γ is:
γ is the angle of acoustic axis plane and central plane,
Depart from the distance of central plane for the acoustic beam point of crossing, p is that the acoustic beam point of crossing is along the horizontal range of tubing axis.
Wherein,
Computing formula be:
Wherein,
Computing formula be:
For guaranteeing effectively exciting and the coupling good with welded tube welding seam of creeping wave probe, probe need grind into the cambered surface of coincideing with welded tube curvature external diameter, generally can determine a kind of radian specification probe in caliber 5mm～10mm scope.
Chip area for the creeping wave probe of thin-walled alternating-current resistance weld seam design generally is not more than 50mm2, and arbitrary length of side is not more than 8mm in principle, probe beam axis offset angle should be greater than 2 °, and the Main beam offset from vertical does not have significantly bimodal, and frequency is 2.5MHZ.
Designed special-purpose reference block according to the singularity that detects resistance weld pipe, namely cut one section steel pipe at tested steel pipe, processed artificial reflecting body, Fig. 5 is seen in the reference block of design.
Because reference block and the same curvature of tested welded tube can not considered the curvature that detects, the decay of coupling and the compensation of inside and outside wall acoustic beam.The actual testing that utilizes such reference block adjusting sweep velocity and detection sensitivity to be conducive to the production scene.
Adopt A type pulse reflection ultrasonic detection instrument, the system performance of instrument and probe should be tested according to the regulation of JB/T9214 and JB/T10062.Utilize the horizontal through hole reference block of Fig. 5, with the depth adjustment of reflection wave sound path according to 2:1.The wave form varies of directly observing the display screen reflection wave during detection judges that flawless existence is arranged.
Utilize the horizontal through hole of φ 1x30 of Fig. 5, probe is aimed at respectively the φ 1mm through hole that the degree of depth is 2mm and 5mm, probe distance φ 1mm through hole 10mm place is the first point of DAC curve, every interval 5mm gets a bit to 30mm, measure simultaneously the reflection wave amplitude, draw distance-amplitude curve according to measurement result, such as Fig. 6, shown in Figure 7, DAC curve decay 10dB is the evaluation line.The requirement of standard is satisfied in selected sensitivity through actual detection validation.Scanning sensitivity is not less than the evaluation line sensitivity at maximum sound path place.
As shown in Figure 8, creeping wave probe acoustic beam center line should be placed on the detection faces perpendicular to the weld seam center, carries out scanning in weld seam one side apart from the about 20mm in weld seam center place, and the Scanning speed of probe should not surpass 50mm/s.
Send regulation among the engineering Q/GDW384 " steel tube tower in electric transmission line process technology rules " according to Wan Diandong, evaluate the quality of welding joint according to the indicating length of the size of the defect type of welding joint, defective wave amplitude and defective.
When one of following situations occurring, be assessed as not allowable defect:
A) in the time of being judged to be the Dangerous defects such as crackle, incomplete fusion such as the testing staff;
B) the flaw echo panel height is when horizontal through hole DAC+14dB;
C) the flaw echo panel height is when horizontal through hole DAC+10dB and Indicated defect length＞5mm.
It is a kind of detection method of novel efficient that the resistance welding line ultrasonic creeping wave detects, and has the advantages that method is simple, practical, efficient is high; For thin-walled resistance weld seam, designed dedicated probe, precision is high, good stability, satisfies testing requirement; The Special test block of design detects through contrast, can be used for the detection of thin-walled resistance weld seam; Owing to climb the characteristic of ripple, make it than the traditional detection method of pipe with small pipe diameter thin-walled weld seam unique advantage be arranged, should be a kind of quick, directly perceived, brand-new detection means, be the strong of Conventional Ultrasound detection method replenishes.
Should be noted that at last; above content is only in order to illustrate technical scheme of the present invention; but not limiting the scope of the invention; the simple modification that those of ordinary skill in the art carries out technical scheme of the present invention or be equal to replacement does not all break away from essence and the scope of technical solution of the present invention.
Claims (4)
1. a resistance weld pipe weld seam creeping wave testing method comprises supersonic reflectoscope, creeping wave probe, it is characterized in that the method comprises:
Step S100 selects the creeping wave probe specification according to resistance weld pipe curvature;
Step S200, accommodation reflex wave sound journey and depth ratio are 2:1;
Step S300 chooses reference point, and as the first point of DAC curve, interval 5mm gets any to returning the first point successively, measures simultaneously the reflection wave amplitude, draws distance-amplitude curve according to measurement result, and DAC curve decay 10dB is the evaluation line;
Step S400 is placed on the acoustic beam center line of creeping wave probe on the detection faces perpendicular to the weld seam center, carries out scanning in weld seam one side apart from 20～25mm place, weld seam center, and the Scanning speed of probe is no more than 50mm/s;
Step S500 compares the result of detection of step S400 and evaluation line.
2. resistance weld pipe weld seam creeping wave testing method according to claim 1 is characterized in that the method comprises:
Step S400 is placed on the acoustic beam center line of creeping wave probe on the detection faces perpendicular to the weld seam center, carries out scanning in weld seam one side apart from 20mm place, weld seam center, and the Scanning speed of probe is 20～50mm/s.
3. a creeping wave probe that is applied in the resistance weld pipe weld seam creeping wave testing method claimed in claim 1 is characterized in that, described creeping wave probe is twin lamella block form creeping wave probe.
4. creeping wave probe according to claim 3 is characterized in that, the chip area of described creeping wave probe is not more than 50mm2, and arbitrary length of side is not more than 8mm, and the beam axis offset angle of described creeping wave probe is not more than 2 °.
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104634875A (en) * | 2015-02-09 | 2015-05-20 | 西安热工研究院有限公司 | Creeping wave detection method for crack defects of austenitic stainless steel pipe for power station boiler |
| CN107894463A (en) * | 2017-12-28 | 2018-04-10 | 中国石油天然气集团公司管材研究所 | The reference block of ERW steel pipe seam electromagnetic acoustic automatic detections and design method |
| CN109115876A (en) * | 2018-08-01 | 2019-01-01 | 攀枝花天誉工程检测有限公司 | Ultrasonic nondestructive testing method and device |
| WO2019091029A1 (en) * | 2017-11-08 | 2019-05-16 | 江苏金鑫电器有限公司 | Phased array ultrasonic testing method for weld seam of housing welded by using aluminum alloy |
| CN112213385A (en) * | 2019-07-11 | 2021-01-12 | 中国科学院金属研究所 | Ultrasonic creeping wave detection method for butt weld of thin-wall section |
| CN112834616A (en) * | 2021-01-04 | 2021-05-25 | 中车青岛四方机车车辆股份有限公司 | Welding seam detection device and method |
| CN113466341A (en) * | 2021-07-02 | 2021-10-01 | 中国大唐集团科学技术研究院有限公司中南电力试验研究院 | Radial crack creeping wave detection method for outer wall of opening of steam-water pipeline seat |
| CN115684367A (en) * | 2022-12-28 | 2023-02-03 | 中兴海陆工程有限公司 | Design method of crossed creeping wave probe |
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- 2013-01-29 CN CN 201310032801 patent/CN103115963A/en active Pending
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104634875A (en) * | 2015-02-09 | 2015-05-20 | 西安热工研究院有限公司 | Creeping wave detection method for crack defects of austenitic stainless steel pipe for power station boiler |
| WO2019091029A1 (en) * | 2017-11-08 | 2019-05-16 | 江苏金鑫电器有限公司 | Phased array ultrasonic testing method for weld seam of housing welded by using aluminum alloy |
| CN107894463A (en) * | 2017-12-28 | 2018-04-10 | 中国石油天然气集团公司管材研究所 | The reference block of ERW steel pipe seam electromagnetic acoustic automatic detections and design method |
| CN107894463B (en) * | 2017-12-28 | 2023-12-08 | 中国石油天然气集团有限公司 | Reference block for electromagnetic ultrasonic automatic detection of ERW steel pipe weld joint and design method |
| CN109115876A (en) * | 2018-08-01 | 2019-01-01 | 攀枝花天誉工程检测有限公司 | Ultrasonic nondestructive testing method and device |
| CN109115876B (en) * | 2018-08-01 | 2020-10-16 | 攀枝花天誉工程检测有限公司 | Ultrasonic nondestructive testing method and device |
| CN112213385A (en) * | 2019-07-11 | 2021-01-12 | 中国科学院金属研究所 | Ultrasonic creeping wave detection method for butt weld of thin-wall section |
| CN112834616A (en) * | 2021-01-04 | 2021-05-25 | 中车青岛四方机车车辆股份有限公司 | Welding seam detection device and method |
| CN113466341A (en) * | 2021-07-02 | 2021-10-01 | 中国大唐集团科学技术研究院有限公司中南电力试验研究院 | Radial crack creeping wave detection method for outer wall of opening of steam-water pipeline seat |
| CN113466341B (en) * | 2021-07-02 | 2023-09-19 | 中国大唐集团科学技术研究院有限公司中南电力试验研究院 | Radial crack creeping wave detection method for outer wall of steam-water pipeline tube seat open hole |
| CN115684367A (en) * | 2022-12-28 | 2023-02-03 | 中兴海陆工程有限公司 | Design method of crossed creeping wave probe |
| CN115684367B (en) * | 2022-12-28 | 2023-11-10 | 中兴海陆工程有限公司 | Design method of cross type creeping wave probe |
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Application publication date: 20130522 |