N DT Abstracts 41819
40947 Lee, J.P.; Lee, S.L.; Lim, H.T.; Park, D.Y. Ultrasonic/radiographic flaw sizing and its excavation on heavy section welds Proceedings of the 12th World Conference on Non-Destructive Testing, Amsterdam (Netherlands), 23-28 Apr. 1989, Vol. 2, pp. 1080-1083. Edited by J. Boogaard and GM. van Dijk, Elsevier,
Link, R.; Nuding, W.; Wiacker, H.; Busse, H.P.
Weld inspection using real-time radiography International Advances in Nondestructive Testing. Edited by Warren J. McGonnagle. Vol. 14, pp. 143-173, Gordon and Breach Science Publishers( 1989) Real-time radiography has become a very useful technique for nondestructive inspection of welds. This paper describes the technique, discusses the features available with real-time systems, including image processing and automatic defect evaluation, and makes a comparison of this technique to standard film radiography. 41519
1989. The integrity of large structures such as reactor vessels, steam generators or pressurizers is dependent on the examination of the weld junction area Various kinds of defects are involved in the fabrication of heavy section welds. However, because welding discontinuities are randomly oriented and arbitrary in shape, it is very difficult to characterize them with only 0~ nondestructive testing (NDT) method. In this paper, the results of ultrasonic/radiographic examination (UT/RT) were compared with the actual flaw sizes revealed by field excavation. Some UT defects not detected by RT were confirmed by magnetic particle and visual examination (MT and VT) during the grinding of the defects. In addition, the importance of both RT and UT, which are complementary as volumetric examination methods, is discussed with concern for the weld fabrication of large nuclear pressure vessels which will be operated for over 40 years.
Nitzshe, R.; Meyendorf, N.
Process for detecting welding seam defects during radiographic testing German (GDR) Patent 252055/Al/ (2 Dec. 1987) A method is described for detecting welding seam defects during radiographic testing with an image information being obtained which then is fed into an evaluation unit for automatic defect detection or determination of the size and depth of a defect using video equipment. 4150 1
40763
Commiss Energie A tomique
413 IO Compiled by Commission V oj’the International Institute
In 1984, Chevron Petroleum (UK) Limited detected a fractured main horizontal tubular on the Ninian Southern Platform. The failure was initiated from a weld defect in an access window. Two further through- thickness cracks as well as many defects still buried were found in other access windows of the platform. As a result of these defects, a major programme of detailed inspection was established. This paper discusses the techniques used to detect and assess the size of subsurface weld defects and to predict their growth and their impact on the structure’s integrity. Results arc presented from examinations of defects in windows removed which quantify the limitations of wet radiography and underwater ultrasonic techniques. Procedures are discussed for combining the positive aspects of each of these techniques to improve confidence in inspection and repair decisions. Use of probabilistic methods to rationalize cost and risk and to improve strategies for defect monitoring and repair are discussed.
ofWelding
Handbook on the magnetic examination of welds The Welding Institute, UK, 52 pp. (1987) ISBN 0 85300195 2 Covers the basics of magnetic flux leakage testing, and the capabilities and limitations of its application to the detection of surface and near-surface defects in welds. 41168
Silk, M.G.
Weld inspection methods Metals and Materials, Vol. 5, No. 4, pp. 192-196 (Apr. 1989) This general overview presents an outline of the techniques which are available and commonly used for the inspection of welds, touching on their advantages and disadvantages for the tasks of defect detection and sizing. The link between the estimated flaw size and the possible failure of structures is considered, and the ways in which this impinges on the inspection of new structures and structures already in service are indicated. The author also discusses implications for the future development of nondestructive testing.
40711 Kanoh, Y.; Abe, H. Quantitative sizing of a crack in stainless steel weldment by means of electrical potential method (In Japanese) Journal of Japanese Society for Non-Destructive Inspection, Vol. 37, No. 9A, pp. 839-840 (Sep. 1988) 40675 Kobayashi, H.; Ookuho, K.; Ike&, Y.; Wakao, H. Detection of weld trackings using neutron radiography technique (In Japanese) Journal of Japanese Society for Non-Destructive Inspection, Vol.
41145 Hulsey, R.C.; Goolshy, A.D. Nondestructive crack depth measurement in internally weld overlayed clad pressure vessels Proceedings of the 12th World Conference on Non-Destructive Testing, Amsterdam (Netherlands), 23-28 Apr. 1989, Vol. 2, pp. 1749-1752. Edited by J. Boogaard and G.M. van Dijk, Elsevier, 1989. Quantitative crack depth measurements were investigated to evaluate the structural integrity of two pressure vessels with internal cracking in a
37, No. 9A, pp. 767-768 (Sep. 1988) 39934 S.P.
Shut-,M.L.; Vaulin, S.L.; Shcherbinin, V.E.; Mikhailov,
Magnetographic detection of disruptions of integrity in the presence of a reinforcement bead of the welded joint Soviet Journal of Nondestructive Testing, Vol. 23, No. 12, pp.
weld overlay to ensure the vessels were operated within safe operating limits while obtaining maximum useful life. Eddy current, potential drop, and ultrasonic time of flight techniques were used in laboratory and field trials to prove the cracks were confined to the overlay material. The most reliable measurements were obtained using eddy current techniques after calibration on test standards which exactly simulated the vessels weld overlay metallurgy. 40949
Fels, X.R.; Mitchell, J.S.
The detection and assessment of sub-surface weld defects with respect to the structural integrity of Ninian Southern Platform Offshore Inspection, Repair and Maintenance Exhibition and Conference, Aberdeen (United Kingdom) 8-10 Nov. 1988, Offshore Conferences and Exhibitions Ltd.
Automatic ultrasonic defect identification - by image analysis, useful for weld testing European Patent No. 294,255 (7 Dec. 1988)
832-840 (Dec. 1987) The theoretical analysis of the effect of bead geometry, of the dimensions and depth of internal defects, and also of the strength of the magnetizing field on the topography of the field on the surface of the bead of the welded joint is carried out in linear approximation and with an allowance made for the nonlinearity in the approximation of technical saturation. The calculated results are compared with the experimental data for artificial cylindrical defects in simulation and full-size welded joints. It is shown that the agreement between the calculated and experimental data is improved when nonlinearity is taken into account.
Shivarov, K.; Kolarova, M.; Nichev, V.
Non-destructive testing of welds in quality assurance of nuclear power plants components Proceedings of the 12th World Conference on Non-Destructive Testing, Amsterdam (Netherlands), 23-28 Apr. 1989, Vol. 2, pp. 1140-1142. Edited by J. Boogaard and G.M. van Dijk, Elsevier, 1989. Non-destructivetesting is performedon the welded joints in the primary
39819 Goswami, G.L.; Roy, P.R. Location of weld defects by acoustic emission Journal of Acoustic Emission, Vol. 7, No. 2, pp. S40-S42 (Jul./Sep. 1988)
circuit pipelines of 1000 MW WWER-type nuclear reactors. Three NDT methods are applied in 14 arrangements of gamma-irradiation, ultrasound propagation, and liquid penetration aimed at detecting and determining the type. size and location of the internal and surface discontinuities.
Weld quality monitoring, as it stands today, is primarily done by X-ray radiography and ultrasonic testing which can be applied only after welding is complete. The acoustic emission (AE) technique is capable of monitoring both the welding process and weld quality together and can be performed
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