- Email: [email protected]
Robot for real time radiographic inspection of circumferential welds with computer processing of the whol system
:ND T abstracts N D T Abstracts is a current awareness service compiled by the National N D T Centre, Harwell Laboratory, Didcot, Oxon, O X l l 0RA, UK. The entries are drawn from over 500 British and International publications. Each issue concentrates on one or two subject areas, and contains abstracts entered from 1987 to the present.
Real time radiography 39635
Nabel, E.; Heidt, H.
Quick methods of supervising microfocal X-ray sources for real time radiography P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e on N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 3, pp. 1993-1999. P e r g a m o n Press, 3173 pp. (1988) Measuring focal spot sizes of microfocus X-ray tubes by evaluating the edge spread function or the geometric unsharpness on film seems to be a rather reliable method. During normal operation a cheap and fast method is needed to supervise microfocal spots. There are two possibilities for such methods. The first of them consists of imaging very fine structures, wire meshes or star test patterns. Unfortunately all these structures are very thin and therefore gives very low contrast. The second method consists of analysing density profiles on an X-ray television system. Here some countermeasures as high magnification and signal enhancement must be taken against low resolution and high noise levels which may obscure the quantities to be measured. The paper will compare all three methods of measuring focal spot sizes and report experiences on which method to use in which case. 39624
Notea, A.; Pal, D.; Deutsch, M,
39287
Anon.
X-ray real-time imaging (XRTI) for weld inspection. 3rd Progress report W e l d i n g in the W o r l d , Vol. 26, No. 5-6, pp. 100-107 (1988) A third progress report is presented on the use of X-ray real-time imaging (XRTI) for weld inspection. It focuses on the attainable performance of XRTI systems, in industry large financial savings have already been made by using this technique. Although in its early stages, the use of pattern recognition methods may lead to automatic recognition of weld defects by computer in the future. 39285
Shelley, T.
X-rays reveal detail at great depth E u r e k a , Vol. 8, No. 9, pp. 40-43 (Sep. 1988) An extremely small X-ray source less than 6 mm in diameter has been developed which can be placed deep inside test objects to reveal their internal structure in finer detail than has been possible up till now. Real time X-ray pictures are obtained by combining the source with high speed photographic techniques and by pulsing the sources. Some possible industrial and medical uses of this technique are described.
Anon.
Density distribution in cylindrically symmetric objects from a single radiographic image
39284
P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e o n N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sep. 1987. Vol. 3, pp. 2093-2102. P e r g a m o n Press, 3173 pp. (1988) A method is presented for the interpretation of x-ray radiographic images of objects with cylindrical symmetry in material density and elemental composition. The method is based on the inversion of the Abel transform. The effect of the object's geometry was separated from the measured image and the remaining image describes the distribution of the radiation attenuation properties. Near step changes in the attenuation properties, and detectability is reduced due to the Gibb's phenomenon. The region affected may, however, be narrowed down by increasing the density of the data points there. The inversion is demonstrated for simulated data as well as for radiographic images of a ceramic product. This method is suitable for interpretation of digitized film radiographs and for real-time systems.
M a t e r i a l s E v a l u a t i o n , Vol. 45, No. 11, pp. 1266-1267 (Nov. 1987) Real time X-radiographic testing of critical components such as jet engine burner cans is possible with a newly designed and very accurate system which can be used in normal workshop environments. The standard unit uses a 100 keV microfocus source coupled to an image intensifier and fitted with a standard videcon camera. Cost savings accrue as burner cans are inspected before cleaning to that irreparable cans can be scrapped.
39608
Arrondeau, P. Y.; Charbonnier, A.
Robot for r e a l t i m e radiographic inspection of circumferential welds with computer processing of the whole system P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e o n N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 3, pp. 1575-1579. P e r g a m o n Press, 3173 pp. (1988) This system is the result of two pieces of research work conducted jointly by Institut de Soudure and Intersub. The first is aimed at implementing and optimizing real time radiography in the field of welded constructions and developing a computerized system for real time inspection. The second is aimed at implementing this inspection procedure by robotizing the system. This research work led to the development of a robot for the non-destructive testing of underwater pipelines. 39601
Rokhlin, S.L; Guu, A.C.
In-process radiographic monitoring of arc weld penetration P r o c e e d i n g s of the 16th S y m p o s i u m o n N o n d e s t r u c t i v e E v a l u a t i o n , San A n t o n i o , Texas ( U n i t e d States), 21-23 A p r . 1987. pp. 209-217. Nondestructive Testing Information Analysis Center, Texas, USA. In this study real-time radiography is used for in-process weld quality evaluation, with on-line testing of defect formation in the weld and welding process control. In this system, welding current can be remotely controlled during observation and computer processing of weld images. The experimental results are demonstrated for the submerged arc welding process. The welding pool is covered by a thick layer of the welding flux and, therefore, the pool is optically invisible. By using computer data of the gray levels of weld images and their histogram distributions, the three-dimensional shape of the submerged arc pool was studied. The depth of the welding pool can be measured in real time and can be used for weld tracking and process control.
126
Real-time X-radiography of jet engine burner cans
39115
Stewart, P.A.E.
The use of penetrating radiations for the dynamic examination of aero gas turbines P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e on N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 1, pp. 118-133. P e r g a m o n Press, 3173 pp. (1988) A new approach is described to the visualisation and measurement of events within running acro, marine and industrial gas turbines produced by Rolls-Royce. High energy x-rays from an 8 MeV radiographic electron linear accelerator are used to determine metal component movements within the engine on dynamic test. The images are used to confirm integrity and improve performance. A real time x-ray video system provides continual surveillance during a test over a diameter of 250 mm and is used to analyse transient events. 'Cold' neutrons and Positron emitting isotopes have been used to examine the oil distribution within 'Gem' and 'Viper' engines at full scale test. The images captured by these~systems may be digitally image processed and pattern recognition and cross-correlation techniques are also used. Measurements are made from film and video images by specially developed photogrammetric methods. 39107
Berger, H.
Some recent developments in X-ray and neutron inspection methods P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e on N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 1, pp. 155-162. P e r g a m o n Press, 3173 pp. (1988) Several recent advances in radiation inspection methods are discussed in terms of contributions made by American radiation scientists. Developments in radiation sources include a portable, high energy accelerator for x-ray inspection and improved microfocus x-ray sources. Inspection systems discussed include real-time microfocus equipments and backscatter techniques, one of these making use of a novel slot camera. Neutron radiographic developments discussed emphasize movable inspection systems and applications for corrosion detection. Sensitivity for neutron radiographic corrosion detection in aluminum equates to a metal loss of less than 25 microns. It is concluded that developments in radiation testing continue to make radiation inspection more useful. An extensive bibliography is included.
NDT International April 1989
Real time radiography 39635
Nabel, E.; Heidt, H.
Quick methods of supervising microfocal X-ray sources for real time radiography P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e on N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 3, pp. 1993-1999. P e r g a m o n Press, 3173 pp. (1988) Measuring focal spot sizes of microfocus X-ray tubes by evaluating the edge spread function or the geometric unsharpness on film seems to be a rather reliable method. During normal operation a cheap and fast method is needed to supervise microfocal spots. There are two possibilities for such methods. The first of them consists of imaging very fine structures, wire meshes or star test patterns. Unfortunately all these structures are very thin and therefore gives very low contrast. The second method consists of analysing density profiles on an X-ray television system. Here some countermeasures as high magnification and signal enhancement must be taken against low resolution and high noise levels which may obscure the quantities to be measured. The paper will compare all three methods of measuring focal spot sizes and report experiences on which method to use in which case. 39624
Notea, A.; Pal, D.; Deutsch, M,
39287
Anon.
X-ray real-time imaging (XRTI) for weld inspection. 3rd Progress report W e l d i n g in the W o r l d , Vol. 26, No. 5-6, pp. 100-107 (1988) A third progress report is presented on the use of X-ray real-time imaging (XRTI) for weld inspection. It focuses on the attainable performance of XRTI systems, in industry large financial savings have already been made by using this technique. Although in its early stages, the use of pattern recognition methods may lead to automatic recognition of weld defects by computer in the future. 39285
Shelley, T.
X-rays reveal detail at great depth E u r e k a , Vol. 8, No. 9, pp. 40-43 (Sep. 1988) An extremely small X-ray source less than 6 mm in diameter has been developed which can be placed deep inside test objects to reveal their internal structure in finer detail than has been possible up till now. Real time X-ray pictures are obtained by combining the source with high speed photographic techniques and by pulsing the sources. Some possible industrial and medical uses of this technique are described.
Anon.
Density distribution in cylindrically symmetric objects from a single radiographic image
39284
P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e o n N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sep. 1987. Vol. 3, pp. 2093-2102. P e r g a m o n Press, 3173 pp. (1988) A method is presented for the interpretation of x-ray radiographic images of objects with cylindrical symmetry in material density and elemental composition. The method is based on the inversion of the Abel transform. The effect of the object's geometry was separated from the measured image and the remaining image describes the distribution of the radiation attenuation properties. Near step changes in the attenuation properties, and detectability is reduced due to the Gibb's phenomenon. The region affected may, however, be narrowed down by increasing the density of the data points there. The inversion is demonstrated for simulated data as well as for radiographic images of a ceramic product. This method is suitable for interpretation of digitized film radiographs and for real-time systems.
M a t e r i a l s E v a l u a t i o n , Vol. 45, No. 11, pp. 1266-1267 (Nov. 1987) Real time X-radiographic testing of critical components such as jet engine burner cans is possible with a newly designed and very accurate system which can be used in normal workshop environments. The standard unit uses a 100 keV microfocus source coupled to an image intensifier and fitted with a standard videcon camera. Cost savings accrue as burner cans are inspected before cleaning to that irreparable cans can be scrapped.
39608
Arrondeau, P. Y.; Charbonnier, A.
Robot for r e a l t i m e radiographic inspection of circumferential welds with computer processing of the whole system P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e o n N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 3, pp. 1575-1579. P e r g a m o n Press, 3173 pp. (1988) This system is the result of two pieces of research work conducted jointly by Institut de Soudure and Intersub. The first is aimed at implementing and optimizing real time radiography in the field of welded constructions and developing a computerized system for real time inspection. The second is aimed at implementing this inspection procedure by robotizing the system. This research work led to the development of a robot for the non-destructive testing of underwater pipelines. 39601
Rokhlin, S.L; Guu, A.C.
In-process radiographic monitoring of arc weld penetration P r o c e e d i n g s of the 16th S y m p o s i u m o n N o n d e s t r u c t i v e E v a l u a t i o n , San A n t o n i o , Texas ( U n i t e d States), 21-23 A p r . 1987. pp. 209-217. Nondestructive Testing Information Analysis Center, Texas, USA. In this study real-time radiography is used for in-process weld quality evaluation, with on-line testing of defect formation in the weld and welding process control. In this system, welding current can be remotely controlled during observation and computer processing of weld images. The experimental results are demonstrated for the submerged arc welding process. The welding pool is covered by a thick layer of the welding flux and, therefore, the pool is optically invisible. By using computer data of the gray levels of weld images and their histogram distributions, the three-dimensional shape of the submerged arc pool was studied. The depth of the welding pool can be measured in real time and can be used for weld tracking and process control.
126
Real-time X-radiography of jet engine burner cans
39115
Stewart, P.A.E.
The use of penetrating radiations for the dynamic examination of aero gas turbines P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e on N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 1, pp. 118-133. P e r g a m o n Press, 3173 pp. (1988) A new approach is described to the visualisation and measurement of events within running acro, marine and industrial gas turbines produced by Rolls-Royce. High energy x-rays from an 8 MeV radiographic electron linear accelerator are used to determine metal component movements within the engine on dynamic test. The images are used to confirm integrity and improve performance. A real time x-ray video system provides continual surveillance during a test over a diameter of 250 mm and is used to analyse transient events. 'Cold' neutrons and Positron emitting isotopes have been used to examine the oil distribution within 'Gem' and 'Viper' engines at full scale test. The images captured by these~systems may be digitally image processed and pattern recognition and cross-correlation techniques are also used. Measurements are made from film and video images by specially developed photogrammetric methods. 39107
Berger, H.
Some recent developments in X-ray and neutron inspection methods P r o c e e d i n g s of the 4th E u r o p e a n C o n f e r e n c e on N o n - D e s t r u c t i v e Testing, L o n d o n ( U n i t e d K i n g d o m ) , 13-17 Sop. 1987. Vol. 1, pp. 155-162. P e r g a m o n Press, 3173 pp. (1988) Several recent advances in radiation inspection methods are discussed in terms of contributions made by American radiation scientists. Developments in radiation sources include a portable, high energy accelerator for x-ray inspection and improved microfocus x-ray sources. Inspection systems discussed include real-time microfocus equipments and backscatter techniques, one of these making use of a novel slot camera. Neutron radiographic developments discussed emphasize movable inspection systems and applications for corrosion detection. Sensitivity for neutron radiographic corrosion detection in aluminum equates to a metal loss of less than 25 microns. It is concluded that developments in radiation testing continue to make radiation inspection more useful. An extensive bibliography is included.
NDT International April 1989