- Email: [email protected]
Geophysical tomography for imaging water movement in welded tuff
N DT Abstracts 38510 Fletcher, MJ. Fully automatic inspection of welds now a reality Welding and Metal Fabrication, Vol. 56, No. 2, pp. 70-72 (Mar. 1988) Recent trends in industrial radiography have offered the welding and casting industries the opportunity to identify very small defects at very high speeds, fully automatically during fabrication. The production of X ray images directly onto a video monitor, coupled with image processing and storage on laser or optical disc have all combined to produce this breakthrough.
Ghosh, J.K.; Panakkal, J.P.; Chandrasekharan, K.N.; Roy, P.R. A combined X-radiography-gamma-autoradiography ( X G A R ) technique for characterisation of welded nuclear fuel pins 38203
l lth World Conference on Nondestructive Testing, Las Vegas, Nevada (United States), 3-8 Nov. 1985. Vol. 2, pp. 1174-1180. Taylor Publishing Co., Dallas (1985). Nuclear fuel pins undergo insl:ection at various stages of fabrication to ensure that they conform to spe,cifications. A typical nuclear fuel pin containing fuel pellets is closed at both ends by welding end plugs. There is always a need for a final inspection step to guarantee that the end product does not suffer from any major deviation. The correct loading of all internal components, enrichment of fuel pellets and freedom from plutonium agglomerates particularly, in plutonium bearing fuels can he assured by employing this final nondestructive test on the finished fuel pins. A combined X-radiography-gamma onto radiography (XGAR) technique has been successfully employed in evaluating all the above mentioned characteristics during the inspection of experimental thermal and fast reactor fuel pins. This paper describes the experimental techniques used in detail and presents typical examples of anomalies observed during the inspection of experimental mixed oxide (U,Pu)O fuel and mixed carbide (U,Pu)C fuel fabricated in this cen'a'e.
Halmshaw, R. An analysis of the performance of X.ray television-fluoroscopic equipment in weld inspection 37903
Materials Evaluation, Vol. 45, No. 11, pp. 1298-1302 (Nov. 1987) X-ray television-fluoroscopic iaspection (XRTI - often called real-time radiography) is briefly described. With modern equipment that uses digital image storage and processing, il is suggested that the chief cause of reduction in image quality, relative to the quality obtained by film radiography, is the larger image unsharpness. Values of total image unsharpness are estimated and used to calculate the crack sensitivities obtainable with XRTI equipment compared to those obtainable with film radiography.
Munro, J.J.; McNulty, R.E.; Nuding, W.; Busse, H.P.; Wiacker, H.; Link, R.; Sauerwein, K.; Grimm, R. Weld inspection by real-time radioscopy 37902
Materials Evaluation, Vol. 45, No. 11, pp. 1303-1309 (Nov. 1987) A real-time X-ray inspection system of high-contrast sensitivity is described. Results in the area of weld inspection provide image- quality indicator (IQI) sensitivities equal to or better than those specified by the standards for X-ray film inspection. The system consists of an X-ray image intensifier and an image proce,;sor. The paper discusses the system components and presents the results of several different types of weld inspection. One of the more important future aspects of real-time radioscopy is the automated evaluation of weldment radiographs. The current state of development in this field is described.
Lozev, M.; Yordanov, D.; Mikhovski, M.; Popov, A. Analysis of the results of radiographic inspection of welded joints in chemical machine-building 37897
British Industrial and Scientif:tc International Translation Service, London (United Kingdom), BISI-24975, 8 pp. (Jun. 1986). (Translated from Mashinostroene, No. 5, pp. 206-209 1985) Probabilistic and statistical methods applied to the non-destructive testing of welded joints can supplement the functions of inspection, thus converting it into an active factor for determining and maintaining a preset quality in the joints at all stages of production. The purpose of this paper is to evaluate, by mathematical statistical methods, the presence of defects in welds determined by non-destructive radiographic testing, and the causes of deterioration in the quality of welded joints under production conditions. The work is a basis for applying statistical methods to analysis and control of the quality of welds in chemical machine-building.
191
37831 saeki, Y.; Sofue, T.; Watanabe, T. The spotty mottling appearing on radiographs of austenitic stainless steel weldments British Journal of Nondestructive Testing, Vol. 30, No. 1, pp. 19-21 (Jan. 1988) The spotty mottling appearing on radiographs of austenltic stainless steel weldments has been studied, and it is concluded that it is caused by diffraction from the columnar crystals grown vertically upward at the root of the bead. The welds that show the spotty mottling on their radiographs exhibit a reduced bend strength. 36858 Anon. X-ray real time imaging for weld inspection: 2nd progress report Welding in the World, Vol.25, No. 1/2, pp. 10-14 (1987) The first progress report, published in March 1986, formed an introduction to the subject of X-ray real-time imaging, which is a technique to produce a radiographic-type image on a television monitor, as an alternative to taking a radiograph on film. By digitizing the image into pixels, so that a computer can be used to "process" the image and to enhance its quality, large improvements in image quality are possible, which has led to claims that the XRTI image can he as good as that obtained on a conventional film radiograph. The potential advantages of XRTI in speed of inspection, reduction in operating costs, etc., are self-evident. This second progress report details further aspects of the method and the equipment required. 36598 Anon X-ray real-time imaging for weld inspection: IIW 2nd progress report British Journal of Nondestructive Testing, Vol. 29, No. 1, pp. 22-24 (Jan. 1987) The first progress report, published in March 1986, formed an introduction to the subject of X-ray real-time imaging, which is a technique to produce a radiographic-type image on a television monitor, as an alternative to taking a radiograph on film. By digitising the image into pixels, so that a computer can be used to "process" the image and to enhance its quality, large improvements in image quality are possible, which has led to claims that the XRTI image can he as good as that obtained on a conventional film radiograph. The potential advantages of XRTI in speed of inspection, reduction in operating costs, etc are self-evident. This second progress report details further aspects of the method and the equipment required. 36589 Daum, W.; Rose, P.; Heidt, H.; Builtjes, J.H. Automatic recognition of weld defects in x-ray inspection British Journal of Nondestructive Testing, Vol. 29, No. 2, pp. 79-81 (Mat. 1987) The main basis for automatic image analysis in X-ray inspection of welds is a segmentation algorithm which detects and marks the defects reliably in the radiograph. The problem for the defect segmentation is that in many cases, the defect representation is superimposed on other image structures due to the shape of the welding seam. By a sophisticated background modelling technique it is nevertheless possible to achieve automatic defect recognition. A comparison between a visual and an automatic evaluation shows the efficiency of this method. 36588 Johnson, J.A.; Carlson, N.M.; Kunerth, D.C. Feasibility tests of observing weld pools using real-time radiography EG and G Idaho, Inc., Idaho Falls (United States), EGG-SD-7338, DE87- 000461, 19pp. (Jul. 1986) This report describes the preliminary analytic and experimental work conducted at the Idaho National Engineering Laboratory (INEL) to determine the feasibility of using real-time radiography to observe the formation and properties of molten weld pools. The calculations show that the expected density changes in steel due to the weld pool could be observable in ideal circumstances. Subsequent experiments, using available equipment without any special adaptations, confirmed the analytic results. The following sections give a short summary of the important factors in standard radiography, the preliminary analysis for weld pool imaging, a discussion of the experimental technique and results, and a summary and recommendations.
Daily, W.; Ramirez, A. Geophysical tomography for imaging water movement in welded tuff 36577
Lawrence Berkeley Laboratory, California (United States) UCRL95078, 6pp. (1 Sup. 1986)
N DT Abstracts
Alterant tomography has been evaluated for its ability to delineate insitu water flow paths in a fractured welded-tuff rock mass. The evaluation involved a field experiment in which tomographs of electromagnetic attenuation factor (or attenuation rate) at 300 MHz were made before, during, and after the introduction to the rock of two different water-based tracers: a plain water and dye solution, and salt water and dye. Alterant tomographs were constructed by subtracting, cell by cell, the attenuation factors derived from measurements before each tracer was added to the rock mass from the attenuation factors derived after each tracer was added. The
alterant tomographs were compared with other evidence of water movement in the rock: boroscope logs of fractures, and postexperiment cores used to locate the dye tracer on the fractured surfaces. These comparisons indicate that alterant tomography is suitable for mapping water flow through fractures and that it may be useful in inferring which of the fractures are hydrologically connected in the image plane. The technique appears to be sensitive enough to delineate flow through a single fracture and to define fractures with a spatial resolution of about 10 cm on an imaging scale of a few meters.
T h e s u b j e c t s c o v e r e d in p r e v i o u s issues f r o m F e b r u a r y 1993 o n w a r d s are: A c o u s t i c and ultrasonic measurement o f e l a s t i c c o n s t a n t s - 27(1); A c o u s t i c e m i s s i o n t e s t i n g o f pressure vessels - 26(6); Bridge inspection - 28(6); Condition monitoring using acoustic and thermal t e c h n i q u e s 27(4); Eddy current probes 28(4); M a g n e t i c flux l e a k a g e - 26(1); Microwave N D T - 27(6); N D T in r a i l w a y s - 26(4); N D T using h a c k s c a t t e r o f ultrasound - 26(5); N D T using C o m p t o n s c a t t e r i n g - 28(3); N e u r a l n e t w o r k s in ultrasonic and acoustic t e s t i n g - 29(1); Positron annihilation - 27(5); Radar inspection in civil engineering - 28(5); Radiography of welds - 29(3); Synthetic aperture s i g n a l p r o c e s s i n g - 26(3); T h e r m o g r a p h y o f c o m p o s i t e s - 26(2); U l t r a s o n i c N D E o f a i r c r a f t - 27(3); X-ray tomography - 27(2) Each entry in NDT Abstracts consists of the serial number in the National NDT Centre Information Store for identification purposes; the title of the paper, book or report; the name of the author; the name of the source journal or document and the abstracts. Where necessary, author's names and the title of foreign journals have been transliterated into the Latin alphabet according to British Standard BS 2979:1958.
Information Service, US Department of Commerce, Springfield, Virginia 22151, USA. British and foreign standards can be obtained from Sales Department, British Standards Institution, 101 Pentonville Road, London N1 9ND; and British and foreign patents from the Patents Office Sales Branch, Block C, Station Square House, St Mary Cray, Orpington, Kent BR5 3RD.
Availabilityof Publications
Information-retrievalService
Most papers listed may be obtained as loans or copies via local library or direct from Loans Department, British Library Document Supply Centre, Bost Spa, Wetherby, Yorkshire LS23 7BQ. Details of the British Lending Library's UK and International Services may be obtained from The Director, British Library Lending Division. Technical reports are also available from the Loans Department of the British Lending Library and in the USA from the National Technical
All entries are indexed in a computerized retrieval system, located at Harwell, which allows rapid searching of information relevant to any particular inspection problem. This service is available to both UK and overseas organizations through the National NDT Centre's Qualtis Subscription Scheme - further details are available from Phil Lawrence on Abingdon (01235) 433391. © 1996 United Kingdom Atomic Energy Authority
192
Ghosh, J.K.; Panakkal, J.P.; Chandrasekharan, K.N.; Roy, P.R. A combined X-radiography-gamma-autoradiography ( X G A R ) technique for characterisation of welded nuclear fuel pins 38203
l lth World Conference on Nondestructive Testing, Las Vegas, Nevada (United States), 3-8 Nov. 1985. Vol. 2, pp. 1174-1180. Taylor Publishing Co., Dallas (1985). Nuclear fuel pins undergo insl:ection at various stages of fabrication to ensure that they conform to spe,cifications. A typical nuclear fuel pin containing fuel pellets is closed at both ends by welding end plugs. There is always a need for a final inspection step to guarantee that the end product does not suffer from any major deviation. The correct loading of all internal components, enrichment of fuel pellets and freedom from plutonium agglomerates particularly, in plutonium bearing fuels can he assured by employing this final nondestructive test on the finished fuel pins. A combined X-radiography-gamma onto radiography (XGAR) technique has been successfully employed in evaluating all the above mentioned characteristics during the inspection of experimental thermal and fast reactor fuel pins. This paper describes the experimental techniques used in detail and presents typical examples of anomalies observed during the inspection of experimental mixed oxide (U,Pu)O fuel and mixed carbide (U,Pu)C fuel fabricated in this cen'a'e.
Halmshaw, R. An analysis of the performance of X.ray television-fluoroscopic equipment in weld inspection 37903
Materials Evaluation, Vol. 45, No. 11, pp. 1298-1302 (Nov. 1987) X-ray television-fluoroscopic iaspection (XRTI - often called real-time radiography) is briefly described. With modern equipment that uses digital image storage and processing, il is suggested that the chief cause of reduction in image quality, relative to the quality obtained by film radiography, is the larger image unsharpness. Values of total image unsharpness are estimated and used to calculate the crack sensitivities obtainable with XRTI equipment compared to those obtainable with film radiography.
Munro, J.J.; McNulty, R.E.; Nuding, W.; Busse, H.P.; Wiacker, H.; Link, R.; Sauerwein, K.; Grimm, R. Weld inspection by real-time radioscopy 37902
Materials Evaluation, Vol. 45, No. 11, pp. 1303-1309 (Nov. 1987) A real-time X-ray inspection system of high-contrast sensitivity is described. Results in the area of weld inspection provide image- quality indicator (IQI) sensitivities equal to or better than those specified by the standards for X-ray film inspection. The system consists of an X-ray image intensifier and an image proce,;sor. The paper discusses the system components and presents the results of several different types of weld inspection. One of the more important future aspects of real-time radioscopy is the automated evaluation of weldment radiographs. The current state of development in this field is described.
Lozev, M.; Yordanov, D.; Mikhovski, M.; Popov, A. Analysis of the results of radiographic inspection of welded joints in chemical machine-building 37897
British Industrial and Scientif:tc International Translation Service, London (United Kingdom), BISI-24975, 8 pp. (Jun. 1986). (Translated from Mashinostroene, No. 5, pp. 206-209 1985) Probabilistic and statistical methods applied to the non-destructive testing of welded joints can supplement the functions of inspection, thus converting it into an active factor for determining and maintaining a preset quality in the joints at all stages of production. The purpose of this paper is to evaluate, by mathematical statistical methods, the presence of defects in welds determined by non-destructive radiographic testing, and the causes of deterioration in the quality of welded joints under production conditions. The work is a basis for applying statistical methods to analysis and control of the quality of welds in chemical machine-building.
191
37831 saeki, Y.; Sofue, T.; Watanabe, T. The spotty mottling appearing on radiographs of austenitic stainless steel weldments British Journal of Nondestructive Testing, Vol. 30, No. 1, pp. 19-21 (Jan. 1988) The spotty mottling appearing on radiographs of austenltic stainless steel weldments has been studied, and it is concluded that it is caused by diffraction from the columnar crystals grown vertically upward at the root of the bead. The welds that show the spotty mottling on their radiographs exhibit a reduced bend strength. 36858 Anon. X-ray real time imaging for weld inspection: 2nd progress report Welding in the World, Vol.25, No. 1/2, pp. 10-14 (1987) The first progress report, published in March 1986, formed an introduction to the subject of X-ray real-time imaging, which is a technique to produce a radiographic-type image on a television monitor, as an alternative to taking a radiograph on film. By digitizing the image into pixels, so that a computer can be used to "process" the image and to enhance its quality, large improvements in image quality are possible, which has led to claims that the XRTI image can he as good as that obtained on a conventional film radiograph. The potential advantages of XRTI in speed of inspection, reduction in operating costs, etc., are self-evident. This second progress report details further aspects of the method and the equipment required. 36598 Anon X-ray real-time imaging for weld inspection: IIW 2nd progress report British Journal of Nondestructive Testing, Vol. 29, No. 1, pp. 22-24 (Jan. 1987) The first progress report, published in March 1986, formed an introduction to the subject of X-ray real-time imaging, which is a technique to produce a radiographic-type image on a television monitor, as an alternative to taking a radiograph on film. By digitising the image into pixels, so that a computer can be used to "process" the image and to enhance its quality, large improvements in image quality are possible, which has led to claims that the XRTI image can he as good as that obtained on a conventional film radiograph. The potential advantages of XRTI in speed of inspection, reduction in operating costs, etc are self-evident. This second progress report details further aspects of the method and the equipment required. 36589 Daum, W.; Rose, P.; Heidt, H.; Builtjes, J.H. Automatic recognition of weld defects in x-ray inspection British Journal of Nondestructive Testing, Vol. 29, No. 2, pp. 79-81 (Mat. 1987) The main basis for automatic image analysis in X-ray inspection of welds is a segmentation algorithm which detects and marks the defects reliably in the radiograph. The problem for the defect segmentation is that in many cases, the defect representation is superimposed on other image structures due to the shape of the welding seam. By a sophisticated background modelling technique it is nevertheless possible to achieve automatic defect recognition. A comparison between a visual and an automatic evaluation shows the efficiency of this method. 36588 Johnson, J.A.; Carlson, N.M.; Kunerth, D.C. Feasibility tests of observing weld pools using real-time radiography EG and G Idaho, Inc., Idaho Falls (United States), EGG-SD-7338, DE87- 000461, 19pp. (Jul. 1986) This report describes the preliminary analytic and experimental work conducted at the Idaho National Engineering Laboratory (INEL) to determine the feasibility of using real-time radiography to observe the formation and properties of molten weld pools. The calculations show that the expected density changes in steel due to the weld pool could be observable in ideal circumstances. Subsequent experiments, using available equipment without any special adaptations, confirmed the analytic results. The following sections give a short summary of the important factors in standard radiography, the preliminary analysis for weld pool imaging, a discussion of the experimental technique and results, and a summary and recommendations.
Daily, W.; Ramirez, A. Geophysical tomography for imaging water movement in welded tuff 36577
Lawrence Berkeley Laboratory, California (United States) UCRL95078, 6pp. (1 Sup. 1986)
N DT Abstracts
Alterant tomography has been evaluated for its ability to delineate insitu water flow paths in a fractured welded-tuff rock mass. The evaluation involved a field experiment in which tomographs of electromagnetic attenuation factor (or attenuation rate) at 300 MHz were made before, during, and after the introduction to the rock of two different water-based tracers: a plain water and dye solution, and salt water and dye. Alterant tomographs were constructed by subtracting, cell by cell, the attenuation factors derived from measurements before each tracer was added to the rock mass from the attenuation factors derived after each tracer was added. The
alterant tomographs were compared with other evidence of water movement in the rock: boroscope logs of fractures, and postexperiment cores used to locate the dye tracer on the fractured surfaces. These comparisons indicate that alterant tomography is suitable for mapping water flow through fractures and that it may be useful in inferring which of the fractures are hydrologically connected in the image plane. The technique appears to be sensitive enough to delineate flow through a single fracture and to define fractures with a spatial resolution of about 10 cm on an imaging scale of a few meters.
T h e s u b j e c t s c o v e r e d in p r e v i o u s issues f r o m F e b r u a r y 1993 o n w a r d s are: A c o u s t i c and ultrasonic measurement o f e l a s t i c c o n s t a n t s - 27(1); A c o u s t i c e m i s s i o n t e s t i n g o f pressure vessels - 26(6); Bridge inspection - 28(6); Condition monitoring using acoustic and thermal t e c h n i q u e s 27(4); Eddy current probes 28(4); M a g n e t i c flux l e a k a g e - 26(1); Microwave N D T - 27(6); N D T in r a i l w a y s - 26(4); N D T using h a c k s c a t t e r o f ultrasound - 26(5); N D T using C o m p t o n s c a t t e r i n g - 28(3); N e u r a l n e t w o r k s in ultrasonic and acoustic t e s t i n g - 29(1); Positron annihilation - 27(5); Radar inspection in civil engineering - 28(5); Radiography of welds - 29(3); Synthetic aperture s i g n a l p r o c e s s i n g - 26(3); T h e r m o g r a p h y o f c o m p o s i t e s - 26(2); U l t r a s o n i c N D E o f a i r c r a f t - 27(3); X-ray tomography - 27(2) Each entry in NDT Abstracts consists of the serial number in the National NDT Centre Information Store for identification purposes; the title of the paper, book or report; the name of the author; the name of the source journal or document and the abstracts. Where necessary, author's names and the title of foreign journals have been transliterated into the Latin alphabet according to British Standard BS 2979:1958.
Information Service, US Department of Commerce, Springfield, Virginia 22151, USA. British and foreign standards can be obtained from Sales Department, British Standards Institution, 101 Pentonville Road, London N1 9ND; and British and foreign patents from the Patents Office Sales Branch, Block C, Station Square House, St Mary Cray, Orpington, Kent BR5 3RD.
Availabilityof Publications
Information-retrievalService
Most papers listed may be obtained as loans or copies via local library or direct from Loans Department, British Library Document Supply Centre, Bost Spa, Wetherby, Yorkshire LS23 7BQ. Details of the British Lending Library's UK and International Services may be obtained from The Director, British Library Lending Division. Technical reports are also available from the Loans Department of the British Lending Library and in the USA from the National Technical
All entries are indexed in a computerized retrieval system, located at Harwell, which allows rapid searching of information relevant to any particular inspection problem. This service is available to both UK and overseas organizations through the National NDT Centre's Qualtis Subscription Scheme - further details are available from Phil Lawrence on Abingdon (01235) 433391. © 1996 United Kingdom Atomic Energy Authority
192