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Filmless X-ray evaluation of structures made of light materials
N DT Abstracts contrast for our high energy real-time imaging. RTR systems with improved performance characteristics and proper translational/rotational staging were adapted for computed tomography applications.
Ion, C. Codes and standards for radiographic inspection comparison analysis (In Romanian; English abstract) 55768
Simpozionul Asociatiei Romane de Examinari Nedistructive, Hunedoara (Romania), 11-13 May 1944. Vol. l-A, pp. 68-86. ARoENd (1994) An analysis is made for industrial condition and acceptance criteria for industrial radiography as specified in the various international and national codes and standards. This asked a comparison of the requirements from the following codes and standards: -ISO, ASME, DIN and ISCIR. These requirements are relative to: - personal authorization, inspection condition: films and screens, radiographic density, source to film distance; energy of X-rays and selection of gamma sources, unsharpness (geometric, inherent and total) sensitivity and acceptance criteria for welds and castings. Finally, a study is presented of the compatibility of various IQI used in the radiographic examination.
55330 Link, R. Role of imaging sensors in radiation methods Welding in the World, Vol. 33, No. 3, pp. 148-151 (t994) A comparison between the different imaging systems in the radioscopic field is given (X-ray image intensifier based systems, open screen systems, systems with linear diodes). The features and tasks of an image processing system are listed.
McFarland, E.W.; Dai, H.; Na, H.; Lanza, R. Segmented array reconstructions for tomographic imaging of large objects: theory and an application to neutron computed tomography 53506
IEEE Transactions on Nuclear Science, Vol. 40, No. 4, pp. 1275-1281 (Aug. 1993) We have developed a position sensitive neutron detector system using a LiF-ZnS scintillator screen and a cooled charge coupled device (CCD) camera. Large arrays of these individual detectors can be assembled to image large areas simultaneously at high resolution. By using the inherent segmentation of the detector, the reconstruction problem can be reduced to one of several small area reconstructions performed in parallel. A parallel tomographic reconstruction scheme based on segmented arrays is presented.
Hove Jensen, T. Filmless X-ray evaluation of structures made of light materials 55760
NDT&E International, Vol. 27, No. 2, pp. 89-96 (Apr. 1994) A fllmless X-ray imaging system is described in which an inexpensive CCD-based video camera is used to photograph the image from a simple fluorescent screen. The image can be displayed on a monitor and stored for computerized image processing. The formation of differential images by subtraction is a powerful technique for evaluation of structures in which the important parts are made of light materials such as polymers and plastics. It is even possible to obtain good images of light parts hidden behind dense materials. Examples presented include X-rays of adhesive bonds in windmill blades, insulation foam in district heating pipes, and foam cores as well as filler joints of sandwich materials. In all of these structures it was possible to detect voids. An example of fracture mapping with the aid of a liquid contrast medium is also shown.
53193 Smith, C.R.; Erker, J.W. Low cost, high resolution D R / C T d e t e c t o r "Quality Through NDT: A Partner for Success". 1992 ASNT Fall Conference and Quality Testing Show, Chicago, Illinois (United States), 16-20 Nov. 1992. pp. 188-190 ASNT (1993) An improved x-ray detector system has been developed and fielded for better performance in digital radiography and computed tomography applications. The x-ray detector array consists of a gadolinium oxysulfide scintillation phosphor screen optically coupled to a linear photodiode army, with a fiber optic entrance window. The phosphor screen is 250 microns thick by 2.5 mm deep (in the direction of the x- ray beam) by 50 mm long. The diode array is an EG&G Reticon, RL2048S, monolithic self-scanning linear photodiode array with 2048 photodiode sensor elements with 25 micron center-to-center spacing. The device consists of a row of photodiodes, each with an associated storage capacitor on which to integrate photo current and a multiplex switch for readout by an independent integrated shift register.
Assuncao, M.P.M.; Pugliesi, R.; De Menezes, M.O. Study of the neutron radiography characteristics for the solid state nuclear track detector MakrofoI-E 55755
Applied Radiation and Isotopes, Vol. 45, No. 8, pp. 851-855 (Aug. 1994) The track-etch method was employed for neutron radiography (NR) purposes. A combination of the solid state nuclear track detector (SSNTD) MakrofoI-E with a natural B converter screen has been used as the image-detector system. In order to determine the best radiographic conditions the image-detector system was irradiated up to neutron exposures around 6 x l0 n/cm and etching times varying from 5 to 45 min were employed to develop the Makrofol-E in a PEW solution a 70C. The best image contrast was obtained for neutron exposures ranging from 1 x 10 to 2 x I0 n/cm, and for 5 rain etching time. For such conditions the track diameter obtained in MakrofoI-E was 1.4 ~tm, the maximum measured optical density was 1.4 and the resolution power of the method ranged from 12 to 40~m. 55590 Balasko, M.; Svah, E.; Nedelik, A. Neutron radiography investigation of compression refrigerators
absorption
Borgonovi, G.M.," Schirato, R.C.; Cappabianca, C. Detector for high resolution computed tomography
53187
and
Non-destructive Testing and Evaluation, Vol. l 1, No. 2-3, pp. 69-76 (1994) Neutron and gamma radiography measurements have been performed on absorption and compression type refrigerators. Radiography images were converted into light by neutron and gamma sensitive converter screens, detected by high sensitivity TV camera, displayed on a monitor, stored by S-VHS recorder and for further analysis a QUANTEL image processing system was used. Characteristic features of absorption aggregates were visualized during different conditions of working processes.
Haskins, J.J.; Dolan, K.W.; Perkins, D.E.; Rikard, D.; Schneberk, D 3. High energy real-time imaging studies 55334
Lawrence Liver National Lab., California (United States), DE93019142/GAR, 6 pp. (Apr. 1993) Performance characteristics of high energy real-time radiography (RTR) systems were optimized by inter-changing components and varying optical coupling methods. Phosphor screens, fiber optic scintillation plates, monolithic high density glass scintillation plates, mirror coatings, different cameras and integration times were studied. X-ray sources were 4- and 9-MeV linear accelerators. High density monolithic glass, high resolution and wide dynamic range CCD cameras, and special focusing and fixturing methods have provided significantly improved spatial resolution and
221
"Quality Through NDT: A Partner for Success". 1992 ASNT Fall Conference and Quality Testing Show, Chicago, lllinois (United States), 16-20 Nov. 1992. pp. 159-161 ASNT (1993) A detector for high resolution industrial tomography applications has been designed, constructed, and tested. The detector is based on the linear scanner array concept, which has been used advantageously for digital radiography. In digital radiography the linear scanner has displayed the following characteristics: high resolution; high dynamic range; simple electronic readout circuit; and possibility of selecting the coverter screen for different energy ranges. The detector described in this paper is based on a commercially available optical linear scanner. The objectives were to obtain good resolution, high stability, and a simple and flexible design.
Nagata, Y.; Yamaji, H.; Hayashi, K.; Kawashima, K.; Hydodo, K.; Kawata, H.; Ando, M. High energy high resolution monochromatic x-ray computed tomography using synchrotron radiation 52518
Nondestructive Characterization of Materials V, Karuizawa (Japan), 27- 30 May 1991. pp. 299-307. Edited by T. Kishi, T. Saito, C. Ruud and R. Green. Iketani Science and Technology Foundation (1993) We have developed a high resolution monochromatic X-ray computed tomography system using synchrotron radiation in the energy range up to 50 keV. The system consists of a double-crystal monochromator employing asymmetric Bragg reflections, a photodiode array detector with a phosphor screen, and a microcomputer for control. CT images with a pixel size of 7.7 [am were obtained. An image subtraction technique for CT images above and below the X-ray absorption edge of iodine was also evaluated for liquid-containing glass capillaries. The results indicate that the system is very useful for nondestructively evaluating fine structures and their constituent elements.
Ion, C. Codes and standards for radiographic inspection comparison analysis (In Romanian; English abstract) 55768
Simpozionul Asociatiei Romane de Examinari Nedistructive, Hunedoara (Romania), 11-13 May 1944. Vol. l-A, pp. 68-86. ARoENd (1994) An analysis is made for industrial condition and acceptance criteria for industrial radiography as specified in the various international and national codes and standards. This asked a comparison of the requirements from the following codes and standards: -ISO, ASME, DIN and ISCIR. These requirements are relative to: - personal authorization, inspection condition: films and screens, radiographic density, source to film distance; energy of X-rays and selection of gamma sources, unsharpness (geometric, inherent and total) sensitivity and acceptance criteria for welds and castings. Finally, a study is presented of the compatibility of various IQI used in the radiographic examination.
55330 Link, R. Role of imaging sensors in radiation methods Welding in the World, Vol. 33, No. 3, pp. 148-151 (t994) A comparison between the different imaging systems in the radioscopic field is given (X-ray image intensifier based systems, open screen systems, systems with linear diodes). The features and tasks of an image processing system are listed.
McFarland, E.W.; Dai, H.; Na, H.; Lanza, R. Segmented array reconstructions for tomographic imaging of large objects: theory and an application to neutron computed tomography 53506
IEEE Transactions on Nuclear Science, Vol. 40, No. 4, pp. 1275-1281 (Aug. 1993) We have developed a position sensitive neutron detector system using a LiF-ZnS scintillator screen and a cooled charge coupled device (CCD) camera. Large arrays of these individual detectors can be assembled to image large areas simultaneously at high resolution. By using the inherent segmentation of the detector, the reconstruction problem can be reduced to one of several small area reconstructions performed in parallel. A parallel tomographic reconstruction scheme based on segmented arrays is presented.
Hove Jensen, T. Filmless X-ray evaluation of structures made of light materials 55760
NDT&E International, Vol. 27, No. 2, pp. 89-96 (Apr. 1994) A fllmless X-ray imaging system is described in which an inexpensive CCD-based video camera is used to photograph the image from a simple fluorescent screen. The image can be displayed on a monitor and stored for computerized image processing. The formation of differential images by subtraction is a powerful technique for evaluation of structures in which the important parts are made of light materials such as polymers and plastics. It is even possible to obtain good images of light parts hidden behind dense materials. Examples presented include X-rays of adhesive bonds in windmill blades, insulation foam in district heating pipes, and foam cores as well as filler joints of sandwich materials. In all of these structures it was possible to detect voids. An example of fracture mapping with the aid of a liquid contrast medium is also shown.
53193 Smith, C.R.; Erker, J.W. Low cost, high resolution D R / C T d e t e c t o r "Quality Through NDT: A Partner for Success". 1992 ASNT Fall Conference and Quality Testing Show, Chicago, Illinois (United States), 16-20 Nov. 1992. pp. 188-190 ASNT (1993) An improved x-ray detector system has been developed and fielded for better performance in digital radiography and computed tomography applications. The x-ray detector array consists of a gadolinium oxysulfide scintillation phosphor screen optically coupled to a linear photodiode army, with a fiber optic entrance window. The phosphor screen is 250 microns thick by 2.5 mm deep (in the direction of the x- ray beam) by 50 mm long. The diode array is an EG&G Reticon, RL2048S, monolithic self-scanning linear photodiode array with 2048 photodiode sensor elements with 25 micron center-to-center spacing. The device consists of a row of photodiodes, each with an associated storage capacitor on which to integrate photo current and a multiplex switch for readout by an independent integrated shift register.
Assuncao, M.P.M.; Pugliesi, R.; De Menezes, M.O. Study of the neutron radiography characteristics for the solid state nuclear track detector MakrofoI-E 55755
Applied Radiation and Isotopes, Vol. 45, No. 8, pp. 851-855 (Aug. 1994) The track-etch method was employed for neutron radiography (NR) purposes. A combination of the solid state nuclear track detector (SSNTD) MakrofoI-E with a natural B converter screen has been used as the image-detector system. In order to determine the best radiographic conditions the image-detector system was irradiated up to neutron exposures around 6 x l0 n/cm and etching times varying from 5 to 45 min were employed to develop the Makrofol-E in a PEW solution a 70C. The best image contrast was obtained for neutron exposures ranging from 1 x 10 to 2 x I0 n/cm, and for 5 rain etching time. For such conditions the track diameter obtained in MakrofoI-E was 1.4 ~tm, the maximum measured optical density was 1.4 and the resolution power of the method ranged from 12 to 40~m. 55590 Balasko, M.; Svah, E.; Nedelik, A. Neutron radiography investigation of compression refrigerators
absorption
Borgonovi, G.M.," Schirato, R.C.; Cappabianca, C. Detector for high resolution computed tomography
53187
and
Non-destructive Testing and Evaluation, Vol. l 1, No. 2-3, pp. 69-76 (1994) Neutron and gamma radiography measurements have been performed on absorption and compression type refrigerators. Radiography images were converted into light by neutron and gamma sensitive converter screens, detected by high sensitivity TV camera, displayed on a monitor, stored by S-VHS recorder and for further analysis a QUANTEL image processing system was used. Characteristic features of absorption aggregates were visualized during different conditions of working processes.
Haskins, J.J.; Dolan, K.W.; Perkins, D.E.; Rikard, D.; Schneberk, D 3. High energy real-time imaging studies 55334
Lawrence Liver National Lab., California (United States), DE93019142/GAR, 6 pp. (Apr. 1993) Performance characteristics of high energy real-time radiography (RTR) systems were optimized by inter-changing components and varying optical coupling methods. Phosphor screens, fiber optic scintillation plates, monolithic high density glass scintillation plates, mirror coatings, different cameras and integration times were studied. X-ray sources were 4- and 9-MeV linear accelerators. High density monolithic glass, high resolution and wide dynamic range CCD cameras, and special focusing and fixturing methods have provided significantly improved spatial resolution and
221
"Quality Through NDT: A Partner for Success". 1992 ASNT Fall Conference and Quality Testing Show, Chicago, lllinois (United States), 16-20 Nov. 1992. pp. 159-161 ASNT (1993) A detector for high resolution industrial tomography applications has been designed, constructed, and tested. The detector is based on the linear scanner array concept, which has been used advantageously for digital radiography. In digital radiography the linear scanner has displayed the following characteristics: high resolution; high dynamic range; simple electronic readout circuit; and possibility of selecting the coverter screen for different energy ranges. The detector described in this paper is based on a commercially available optical linear scanner. The objectives were to obtain good resolution, high stability, and a simple and flexible design.
Nagata, Y.; Yamaji, H.; Hayashi, K.; Kawashima, K.; Hydodo, K.; Kawata, H.; Ando, M. High energy high resolution monochromatic x-ray computed tomography using synchrotron radiation 52518
Nondestructive Characterization of Materials V, Karuizawa (Japan), 27- 30 May 1991. pp. 299-307. Edited by T. Kishi, T. Saito, C. Ruud and R. Green. Iketani Science and Technology Foundation (1993) We have developed a high resolution monochromatic X-ray computed tomography system using synchrotron radiation in the energy range up to 50 keV. The system consists of a double-crystal monochromator employing asymmetric Bragg reflections, a photodiode array detector with a phosphor screen, and a microcomputer for control. CT images with a pixel size of 7.7 [am were obtained. An image subtraction technique for CT images above and below the X-ray absorption edge of iodine was also evaluated for liquid-containing glass capillaries. The results indicate that the system is very useful for nondestructively evaluating fine structures and their constituent elements.