- N D T abstracts NDT Abstracts are compiled by AEA Technology National NDT Centre, Harwell, Oxon, OX11 0RA, UK. The entries are drawn from over 500 British and International publications. Each issue concentrates on one or two subject areas. The subjects covered in previous issues from February 1992 onwards are: Acoustic emission monitoring of fatigue - 25(6); Acoustic techniques for adhesive bond evaluation - 25(2); Artificial intelligence in N D T - 25(1); Characterization of ultrasonic transducers - 25(3); Magnetic flux leakage - 26(1); N D T in railways - 26(4); N D T using bockscatter of ultrasound - 26(5); Synthetic aperture signal processing - 26(3); Theory and modelling of radiography - 25(4); Thermography of composites - 26(2)
Acoustic emission testing of pressure vessels 53828 Lenain, J.-C. Rewiew of the applicants of acoustic emission in industry Revue Pratique de Controle Industriel, Suppl. No. 182, pp. 24-27 (Oct. 1993) This paper show several examples of applications: pressure vessels, spheres, storage tank,.., and so gives an idea about the database available. Also Ae is used as a condition monitoring method (corrosion, leak,...) of storage tank bottom. New developments have been made for testing the aircraft structures such fuselage, wing.., to answer the ageing problem. 53090 Friesel, M.A.; Dawson, J.F. Acoustic emission monitoring of HFIR vessel during hydrostatic testing. Final report Batelle Pacific Northwest Labs., Richland, Washington (United States), DE 92019316/GAR, 52pp. (Aug. 1992) This report discusses the results and conclusions reached from applying acoustic emission monitoring to surveillance of the High Flux Isotope Reactor vessel during pressure testing. The objective of the monitoring was to detect crack growth end/or fluid leakage should it occur during the pressure test. The report addresses the approach, acoustic emission instrumentation, installation, calibration, and test results. 53077 Pellionisz, P.; Szucs, P. Acoustic emission monitoring of pressure vessels International Journal of Pressure Vessels and Piping, Vol. 55, No. 2, pp. 287-294 (1993) This paper summarises the main features of the acoustic emission testing method. A short overview is given of how common failures can be detected at pressure vessel testing and how measurement results are evaluated. Acoustic emission monitoring of pressure vessels for the power plant industry has been introduced also in Hungary: an overview is given and some of the measurement results are presented. 52822 Pellionisz, P.; Gereb, J. Acoustic emission technique at proof tests of nuclear pressure vessels in Hungary Journal of Acoustic Emission, Vol. 10, No. 3-4, pp. 19-23 (1992) One of the most successful applications of acoustic emission (AE) techniques is monitoring pressure tests. This surveillance method has been introduced in Hungary, where four, 440 MW pressurized.water nuclear reactors are in operation. The first application was made in 1987 at the four-year in-service inspection and proof test of the first reactor unit and it has been followed by yearly procedures of inspecting the second, third and fourth reactor units, between 1988-90, The AE investigations performed at Paks Nuclear Power Plant are presented regarding the measurement, data transmission and processing methods, the instrumentation and organization technique. 52813 Keyvan, S.; King, R. The role of acoustic monitoring as a diagnostic tools in n u d e a r reactors
Journal of Acoustic Emission, Vol. 10, No. 3-4, pp. 91-95 (1992) This paper presents the results of a survey on acoustic monitoring applications in light water reactors and an assessment of application of acoustic monitoring technology in Experimental Breeder Reactor II (EBR-ll), the only power producing liquid metal fast breeder reactor in the United States. T ~ main objective of this paper was to obtain information on various applications of acoustic techniques in light water reactors (both
boiling water reactors and pressurized water reactors) and to assess applications for EBR-II from it's past experiences.
52589 Camerini, C S; Rebelio, J M A; Soares, S D Relationship between acoustic emission and C T O D testing for a structural steel NDT&E International, Vol. 25, No. 3, pp 127-133 (1992) The present work investigates whether the required pressure level causes flaw propagation, risking vessel integrity. The material employed was a fine grained normalized C-Mn structural steel (ASTM A 516 gr. 60). Fracture mechanics crack tip opening displacement (CLOD) tests were conducted and the acoustic emission probes were placed on the testpieces, which enabled a correlation to be established at any moment between the crack acoustic behaviour and its CIOD value. Acoustic emission testing may be reliably performed at sufficiently low CTOD values, where the risk of fracture may be discarded.
Akhtar, A; Wong, J Y; Bhuyan, G S; Webster, C T; Kung, D; Gambone, L R; Neufeld, N; Brezden, W J 52588
Acoustic emission testing of steel cylinders for the storage of natural gas on vehicles NDT&E International, Voi, 25, No. 3, pp 115-125 (1992) Acoustic emission testing for the periodic inspection of steel cylinders used for the storage of natural gas on vehicles was investigated. Normal refuelling pressurization does not produce adequate emission to enable structural integrity assessmanL Detection of cracks through 15% or more of the side wall is feasible using overpressurization to 33% above the nominal refuelling pressure. A methodology was developed to distinguish between general corrosion product signals and those primarily associated with cracks. The effects of test interruption and the rate of cylinder pressurization on acoustic emissions were examined. The test method involves the application of one conditioning pressure cycle followed by one overpressure cycle. The sensitivity of the test method is adequate to permit an inspection interval of five years in service. 52586 Christian, H.; Raible, B. Computerized loose parts monitoring system - experience and recent investigations of sound propagation in real structures 9th International Conference on Nondestructive Evaluation in the Nuclear Industry, Tokyo (Japan), 25-28 Apr. 1988, pp. 145-150. Edited by K. lida, J.E. Doherty and X. Edelmann. ASM (1988) It is a requirement of the German Reactor Safety Commission to install loose parts monitoring systems (LPMS) in each German nuclear power plant. Since neither the possible failure position nor the point of time of an event is known, a global and continuously monitoring system is necessary. It is the task of a LPMS to detect and record the solid- born noise signals, to analyse and localize the source of ~ noise. The suitable hardware and software is available with the computerized LPMS KAP 80, Experiences with this system and results will be presented. 52338 Clark, G. C o m m e n t a r y on 'Quantitative Acoustic Emission Source Characterization of Microcracking in Steel' Research in Nondestructive Evaluation, Vol. 4, No. 3, pp. 183-190 (1992) Results published recently by Takatsubo and Kishi concerning acoustic emission during ductile fracture of A533B steel indicated that highamplitude emissions observed were associated with tension/shear mixed-
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International Volume
26 Number
6 1993
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