Предлагается формальная конструкция, обобщающая классический комп-лекс де Рама на широкий спектр моделей математической физики и анализа. Изложение разбито на ряд последовательных определений и элементарных лег-ко проверяемых утверждений, поэтому доказательства приведены лишь в клю-чевых случаях. Линейные операции всюду выполняются над фиксированным числовым полем F = R, C, и, хотя это явно не оговаривается, все вводимые линейные пространства, алгебры и модули по определению или по построению обладают естественными локально выпуклыми топологиями, а их морфизмы непрерывны.Ключевые слова: комплекс де Рама, мультипликатор, дифференцирование, внеш-няя алгебра, граничный оператор, внешний дифференциал, комплекс, ассоциированный с алгеброй, градуировка.
The article describes possibilities of phased array flaw detectors application for testing of railway transport units, such as wheel set axles, all-rolled wheels, solebars of freight cars. The task was to reproduce the standard testing procedures using phased array flaw detectors and demonstrate their advantages in visibility, efficiency, repeatability, results validity. Unfortunately, one of the main advantages of phased array flaw detectors, namely – a possibility to control the focusing depth – are lost while testing of large scale objects. Sector scanning technique with the phased array flaw detectors OmniScan and Isonic 2010 in the minimum configuration was used for the research. In the all cases acoustical images of the following reflectors were obtained within the range of selected angles: saw-cuts in axles, spot-drillings and saw-cuts in wheels, side drilled holes and natural defects in solebars. The Multi Group software (Isonic 2000) at testing of wheel set axles has enabled the testing schemes to be realized with one prism and one phased array instead of several classical piezoelectric transducers. Circumferential testing of all-rolled wheels from internal lateral surface under the roll surface level has allowed transverse cracks and flange embedded defects to be detected. Solebar testing has been more complicated because of a form and irregularity of scanning surface, necessity of its cleaning and a complex profile of back surface. Nevertheless the usage of phased array flaw detectors has made it possible to identify the back surface profile. Application of phased arrays substantially increases testing efficiency and improves visibility of obtained results.
The second part of the article describes possibilities of phased array flaw detectors application for testing of railway transport units, such as solebars of freight cars. The task was to reproduce the standard testing procedures using phased array flaw detectors and demonstrate their advantages in visibility, efficiency, repeatability, results validity. Unfortunately, one of the main advantages of phased array flaw detectors, namely – a possibility to control the focusing depth – is lost while testing of large scale objects. Sector scanning technique with the phased array flaw detectors OmniScan and Isonic 2010 in the minimum configuration was used for the research. In the all cases acoustical images of the side drilled holes and natural defects in solebars were obtained within the range of selected angles. Solebar testing has been more complicated because of a form and irregularity of scanning surface, necessity of its cleaning and a complex profile of back surface. Nevertheless the usage of phased array flaw detectors has made it possible to identify the back surface profile. Application of phased arrays substantially increases testing efficiency and improves visibility of obtained results.
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