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Acoustic emission in delayed fracture of welded joints
N DT Abstracts 45088
Kountouris, IS.; Baker, M.J.
current, visual-optical methods are compared metallographic examination.
Reliability of non-destructive examination of welded joints Dept. Civil engineering, Imperial College London, CESLIC Report OR7,74 pp. (Feb. 1989)
with the results of
44198 Taylor, R.G. NDT of electron beam welded joints (micro-focus and real time X-ray) Advanced Joining of Aerospace Metallic Materials, AGARD-CP398.4 pp. (Jul. 1986)
This report reviews published information from several national and international programmes on detection probabilities and sizing errors. Currently used functions for ‘failure to detect’ probabilities are critically reviewed and new generalised models are proposed for use in updating defect size and occurrence distributions. It is shown that most of the models currently used by industry have not been rigorously fitted to the available data and, furthermore, are unconservative for large defects.
The introduction of electron beam welding (EBW) into the aero engine industry in the early 1960’s has presented many new problems for nondestructive testing (NDT). Recently, significant developments have taken place which has enabled micro-focus X-ray techniques to be used in place of conventional X-ray on EBW and this has resulted in a considerable improvement in defect detection capabilities. An additional bonus has been the reduction in inspection costs and an improvement in productivity.
44796 Vijayendra, M.K.; Murthy, C.R.L.; Rao. A.K. Crack growth in weld region: characterization by acoustic emission Proceedings of the IUTAM Symposium on Elastic Waves and Ultrasonic Nondestructive Evaluation, University of Colorado, Boulder, Colorado (United States), 30 Jul. - 3 Aug. 1989. pp. 369-374 Edited by S.K. Datta, J.D. Achenbach and Y.S. Rajapakse. North - Holland, (1990). ISBN 0 444 874 852. There is a need for a Non-destructive evaluation (NDE) method which
44197
Potapov, V.N.; Belyi, N.G.; Grom, V.S.
On increasing the contrast of flaw images in the radiographic inspection of welds (In Russian) Tekhnicheskaya Diagnostika i Nerazrushayushchii Kontrol, No. 2, pp. ll- 14 (1989) Using the method of a recent application of the theory of small
can discriminate in-service growth of cracks in the three zones to help monitor structural integrity and ensure safety. The classical source location technique is inadequate because the weld region is very narrow. Hence, characterization and location by signal analysis become necessary. An attempt is made to understand and characterize data obtained through controlled experiments specifically designed for evaluation of the three distinct zones in the weld region by Acoustic emission. The experiments and the results are presented in this paper.
perturbations, quantatitive data on the influence of slit diaphragming on the contrast of flaw images during the radiographic inspection of welds have been obtained. Experimental results supporting the theoretical data are presented.
44181 Potapov, V.N.; Belyi, N.G.; Grom, V.S. Increasing the contrast of defect images in radiation inspection of welded joints Technical Diagnostics and Nondestructive Testing, Vol. 1, No. 2, pp. 74-76 (Apr.-Jun. 1989)
44470 Dodd, C.V.; Scott, G.W.; Chihvood, L.D. Eddy-current inspection of shuttle heat exchanger tube welds Oak Ridge National Laboratory, Tennessee (United States), DE90001335/GAR, 17 pp. (1989)
The method of consecutive application of the theory of small perturbations was used to obtain quantitative data on the effect of slit stopping down in radiation inspection of welded joints on the contrast of defect images. The experimental results which confirm the calculated data are presented.
This goal of this project was to develop the system necessary to demonstrate in the laboratory that an eddy-current system can inspect the tubes and welds described above, screening for the existence of flaws equal in size to or larger than the target flaw. The laboratory system was to include the probe necessary to traverse the tubing, the electronics to drive (i.e. electrically excite) the probe and receive and process signals from it, a data display, data recording and playback devices, and microprocessor software or firmware necessary to operate the system.
44173 Gayer, A.; Saya, A.; Shiloh, A. Automatic recognition of welding defects in real-time radiography NDT International, Vol. 23, No. 3, pp. 131-136 (Jun. 1990) This paper describes a real-time radiography configuration for the automatic inspection of welds. The optimal geometrical geometrical imaging configuration is evaluated and discussed in relation to conventional film radiography. For the automatic inspection of X-ray images, a two-step analysis was adopted: a fast search for defective regions, followed by tine identification and location of defects. Two different algorithms, based on the relative irregular behaviour of a defect, were developed for the fast search procedure. The second step. fine identification, can be achieved by a sequential similarity detection algorithm or by a thresholding algorithm. The different methods were applied to various X-ray images of welds and the automatic inspection was evaluated and compared with visual inspection.
44300 Pronin, V.P.; Ivanov, V.I. Acoustic emission in delayed fracture of welded joints Technical Diagnostics and Nondestructive Inspection, Vol. 1, pp. 35-38 (Jan.-Mar. 1989) Delayed fracture tests, used to evaluate the cold cracking resistance of steels in welding, are described here using flat welded specimens of 25KhN3MFA steel by means of acoustic emission (AE) tests. Recording analysis of AE test results permits evaluation of defect risk, propagation dynamics and structure behaviour. AE counts in delayed failure of the welded joint are shown to reflect all stages of the process in relation to the loading level, without necessarily loading the specimen to fracture point
Pereverzev, E.S.; Borshchevskaya, D.G.; Bigus, G.A.; Evina, T.Y.; Tremba, T.S.
44072
Evaluation of the efficiency of inspection of weld defects Technical Diagnostics and Nondestructive Inspection, Vol. I, pp. 31-34 (Jan.-Mar. 1989) This paper reports a comparative evaluation of three nondestructive techniques used to inspect the quality of the welded structures and identify
Teterko, A.Y.; Uchanin, V.N.; Rybakov, V.M.; Emel’yanova, L.N.
44225
Use of eddy-current instruments for detecting oxide films in welds in parts made of aluminium alloys (In Russian) Tekhnicheskaya Diagnostika i Nerazrushayushchii Kontrol, No. 2, pp. 66- 68 (1989)
risks. Welded joints of AMg6 aluminium - magnesium alloy were inspected using radiographic, ultrasonic and acoustic emission tests. Each method detected some of the ten specimen defects, with ultrasonic inspection producing some false positive results. The authors propose triple inspection to ensure complete detection of dangerous weld defects.
The special features of the eddy-current method of testing arc welds in parts made of aluminium alloys are considered. The results of observation of flaws of the oxide-film type by means of eddy-current detectors are presented. The eddy-current visual-optic method is assessed in comparison with the results of metallographic studies.
43982
44209 Teterko, A.Y.; Uchanin, V.N.; Rybakov, B.M.; Emel’yanova, L.N.
Using eddy current devices for detecting oxide films in welded joints in components made of aluminium alloys Technical Diagnostics and Nondestructive Testing, Vol. 1, No. 2, pp. 1 l8- 119 (Apr.-Jun. 1989) The authors examine the special features of the eddy current method of inspection of welded joints in components made of Al alloys using arc welding. The results of detection of defects of the oxide film type with an eddy current flaw detector are presented. The results obtained in the eddy
128
Rohkhlin, S.I.; Guu, A.C.; Cho. K.
Closed-loop radiographic process control of arc welding Proceedings of the 15th Annual Review of Progress in Quantitative Nondestructive Evaluation, La Jolla, California (USA), 3 I Jul. - 5 Aug. 1988. Vol. 8B, pp. 2173-2180. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1989). ISBN o-306-43209-9. In this paper, the implementation of real-time radiography for inprocess control of arc welding is discussed. X-ray penetrating radiation is used for volume observation in the welding pool and the heat-affected zone during the weld process. The advantages of such a technique are on-line testing of defect formation in the weld and the availability of this information for feedback control of weld quality.
Kountouris, IS.; Baker, M.J.
current, visual-optical methods are compared metallographic examination.
Reliability of non-destructive examination of welded joints Dept. Civil engineering, Imperial College London, CESLIC Report OR7,74 pp. (Feb. 1989)
with the results of
44198 Taylor, R.G. NDT of electron beam welded joints (micro-focus and real time X-ray) Advanced Joining of Aerospace Metallic Materials, AGARD-CP398.4 pp. (Jul. 1986)
This report reviews published information from several national and international programmes on detection probabilities and sizing errors. Currently used functions for ‘failure to detect’ probabilities are critically reviewed and new generalised models are proposed for use in updating defect size and occurrence distributions. It is shown that most of the models currently used by industry have not been rigorously fitted to the available data and, furthermore, are unconservative for large defects.
The introduction of electron beam welding (EBW) into the aero engine industry in the early 1960’s has presented many new problems for nondestructive testing (NDT). Recently, significant developments have taken place which has enabled micro-focus X-ray techniques to be used in place of conventional X-ray on EBW and this has resulted in a considerable improvement in defect detection capabilities. An additional bonus has been the reduction in inspection costs and an improvement in productivity.
44796 Vijayendra, M.K.; Murthy, C.R.L.; Rao. A.K. Crack growth in weld region: characterization by acoustic emission Proceedings of the IUTAM Symposium on Elastic Waves and Ultrasonic Nondestructive Evaluation, University of Colorado, Boulder, Colorado (United States), 30 Jul. - 3 Aug. 1989. pp. 369-374 Edited by S.K. Datta, J.D. Achenbach and Y.S. Rajapakse. North - Holland, (1990). ISBN 0 444 874 852. There is a need for a Non-destructive evaluation (NDE) method which
44197
Potapov, V.N.; Belyi, N.G.; Grom, V.S.
On increasing the contrast of flaw images in the radiographic inspection of welds (In Russian) Tekhnicheskaya Diagnostika i Nerazrushayushchii Kontrol, No. 2, pp. ll- 14 (1989) Using the method of a recent application of the theory of small
can discriminate in-service growth of cracks in the three zones to help monitor structural integrity and ensure safety. The classical source location technique is inadequate because the weld region is very narrow. Hence, characterization and location by signal analysis become necessary. An attempt is made to understand and characterize data obtained through controlled experiments specifically designed for evaluation of the three distinct zones in the weld region by Acoustic emission. The experiments and the results are presented in this paper.
perturbations, quantatitive data on the influence of slit diaphragming on the contrast of flaw images during the radiographic inspection of welds have been obtained. Experimental results supporting the theoretical data are presented.
44181 Potapov, V.N.; Belyi, N.G.; Grom, V.S. Increasing the contrast of defect images in radiation inspection of welded joints Technical Diagnostics and Nondestructive Testing, Vol. 1, No. 2, pp. 74-76 (Apr.-Jun. 1989)
44470 Dodd, C.V.; Scott, G.W.; Chihvood, L.D. Eddy-current inspection of shuttle heat exchanger tube welds Oak Ridge National Laboratory, Tennessee (United States), DE90001335/GAR, 17 pp. (1989)
The method of consecutive application of the theory of small perturbations was used to obtain quantitative data on the effect of slit stopping down in radiation inspection of welded joints on the contrast of defect images. The experimental results which confirm the calculated data are presented.
This goal of this project was to develop the system necessary to demonstrate in the laboratory that an eddy-current system can inspect the tubes and welds described above, screening for the existence of flaws equal in size to or larger than the target flaw. The laboratory system was to include the probe necessary to traverse the tubing, the electronics to drive (i.e. electrically excite) the probe and receive and process signals from it, a data display, data recording and playback devices, and microprocessor software or firmware necessary to operate the system.
44173 Gayer, A.; Saya, A.; Shiloh, A. Automatic recognition of welding defects in real-time radiography NDT International, Vol. 23, No. 3, pp. 131-136 (Jun. 1990) This paper describes a real-time radiography configuration for the automatic inspection of welds. The optimal geometrical geometrical imaging configuration is evaluated and discussed in relation to conventional film radiography. For the automatic inspection of X-ray images, a two-step analysis was adopted: a fast search for defective regions, followed by tine identification and location of defects. Two different algorithms, based on the relative irregular behaviour of a defect, were developed for the fast search procedure. The second step. fine identification, can be achieved by a sequential similarity detection algorithm or by a thresholding algorithm. The different methods were applied to various X-ray images of welds and the automatic inspection was evaluated and compared with visual inspection.
44300 Pronin, V.P.; Ivanov, V.I. Acoustic emission in delayed fracture of welded joints Technical Diagnostics and Nondestructive Inspection, Vol. 1, pp. 35-38 (Jan.-Mar. 1989) Delayed fracture tests, used to evaluate the cold cracking resistance of steels in welding, are described here using flat welded specimens of 25KhN3MFA steel by means of acoustic emission (AE) tests. Recording analysis of AE test results permits evaluation of defect risk, propagation dynamics and structure behaviour. AE counts in delayed failure of the welded joint are shown to reflect all stages of the process in relation to the loading level, without necessarily loading the specimen to fracture point
Pereverzev, E.S.; Borshchevskaya, D.G.; Bigus, G.A.; Evina, T.Y.; Tremba, T.S.
44072
Evaluation of the efficiency of inspection of weld defects Technical Diagnostics and Nondestructive Inspection, Vol. I, pp. 31-34 (Jan.-Mar. 1989) This paper reports a comparative evaluation of three nondestructive techniques used to inspect the quality of the welded structures and identify
Teterko, A.Y.; Uchanin, V.N.; Rybakov, V.M.; Emel’yanova, L.N.
44225
Use of eddy-current instruments for detecting oxide films in welds in parts made of aluminium alloys (In Russian) Tekhnicheskaya Diagnostika i Nerazrushayushchii Kontrol, No. 2, pp. 66- 68 (1989)
risks. Welded joints of AMg6 aluminium - magnesium alloy were inspected using radiographic, ultrasonic and acoustic emission tests. Each method detected some of the ten specimen defects, with ultrasonic inspection producing some false positive results. The authors propose triple inspection to ensure complete detection of dangerous weld defects.
The special features of the eddy-current method of testing arc welds in parts made of aluminium alloys are considered. The results of observation of flaws of the oxide-film type by means of eddy-current detectors are presented. The eddy-current visual-optic method is assessed in comparison with the results of metallographic studies.
43982
44209 Teterko, A.Y.; Uchanin, V.N.; Rybakov, B.M.; Emel’yanova, L.N.
Using eddy current devices for detecting oxide films in welded joints in components made of aluminium alloys Technical Diagnostics and Nondestructive Testing, Vol. 1, No. 2, pp. 1 l8- 119 (Apr.-Jun. 1989) The authors examine the special features of the eddy current method of inspection of welded joints in components made of Al alloys using arc welding. The results of detection of defects of the oxide film type with an eddy current flaw detector are presented. The results obtained in the eddy
128
Rohkhlin, S.I.; Guu, A.C.; Cho. K.
Closed-loop radiographic process control of arc welding Proceedings of the 15th Annual Review of Progress in Quantitative Nondestructive Evaluation, La Jolla, California (USA), 3 I Jul. - 5 Aug. 1988. Vol. 8B, pp. 2173-2180. Edited by D.O. Thompson and D.E. Chimenti. Plenum Press (1989). ISBN o-306-43209-9. In this paper, the implementation of real-time radiography for inprocess control of arc welding is discussed. X-ray penetrating radiation is used for volume observation in the welding pool and the heat-affected zone during the weld process. The advantages of such a technique are on-line testing of defect formation in the weld and the availability of this information for feedback control of weld quality.