Ultrasonic Testing of Railway Transport Units with Phased Array Flaw Detectors

NDT World ◽  
2015 ◽  
Vol 18 (3) ◽  
pp. 72-76 ◽  
Author(s):  
Макарова ◽  
Taisiya Makarova ◽  
Мелешко ◽  
Nataliya Meleshko ◽  
Жаринов ◽  
...  
Keyword(s):  
Large Scale ◽  
Phased Array ◽  
Phased Arrays ◽  
Surface Profile ◽  
Piezoelectric Transducers ◽  
Back Surface ◽  
Railway Transport ◽  
Transverse Cracks ◽  
Testing Procedures ◽  
Standard Testing

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.

Ultrasonic Testing of Railway Transport Units with Phased Array Flaw Detectors. Part 2

NDT World ◽  
2015 ◽  
Vol 18 (4) ◽  
pp. 76-80
Author(s):  
Сойфер ◽  
Yuriy Soyfer ◽  
Макарова ◽  
Taisiya Makarova ◽  
Мелешко ◽  
...  
Keyword(s):  
Ultrasonic Testing ◽  
Large Scale ◽  
Phased Array ◽  
Phased Arrays ◽  
Surface Profile ◽  
Back Surface ◽  
Railway Transport ◽  
Complex Profile ◽  
Testing Procedures ◽  
Standard Testing

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.

scholarly journals A Fast Calibration Method for Phased Arrays by Using the Graph Coloring Theory

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4315 ◽  
Author(s):  
Lijie Yang ◽  
Ruirui Dang ◽  
Min Li ◽  
Kailong Zhao ◽  
Chunyi Song ◽  
...  
Keyword(s):  
Graph Coloring ◽  
Large Scale ◽  
Phased Array ◽  
Phased Arrays ◽  
Calibration Method ◽  
Omnidirectional Antenna ◽  
Phase Errors ◽  
Calibration Problem ◽  
Calibration Methods ◽  
Calibration Time

Phased array radars are able to provide highly accurate airplane surveillance and tracking performance if they are properly calibrated. However, the ambient temperature variation and device aging could greatly deteriorate their performance. Currently, performing a calibration over a large-scale phased array with thousands of antennas is time-consuming. To facilitate the process, we propose a fast calibration method for phased arrays with omnidirectional radiation patterns based on the graph coloring theory. This method transforms the calibration problem into a coloring problem that aims at minimizing the number of used colors. By reusing the calibration time slots spatially, more than one omnidirectional antenna can perform calibration simultaneously. The simulation proves this method can prominently reduce total calibration time and recover the radiation pattern from amplitude and phase errors and noise. It is worth noting that the total calibration time consumed by the proposed method remains constant and is negligible compared with other calibration methods.

Development of a Reproducible Method of Formulating and Testing Drilling Fluids

1969 ◽  
Vol 9 (04) ◽  
pp. 403-411 ◽  
Author(s):  
B.K. Sinha ◽  
Harvey T. Kennedy
Keyword(s):  
Large Scale ◽  
Drilling Fluid ◽  
Flow Characteristics ◽  
Field Testing ◽  
Test Methods ◽  
Water Evaporation ◽  
Fluid Loss ◽  
Drilling Fluids ◽  
Testing Procedures ◽  
Asymptotic Values

Abstract Recommendations are made for obtaining consistent and reproducible test data on drilling fluids having identical composition. Previously, such a procedure has been difficult to accomplish even when the fluids were mixed in similar equipment. A survey of work in this area indicates that previous methods have been unsatisfactory because previous methods have been unsatisfactory because (1) the muds are extremely sensitive to the duration and violence of agitation during a normal mixing routine, and (2) gelling of the muds occurs before the properties can reach constant values. This gelling is caused by water evaporation resulting from the increase in temperature associated with the agitation. The work shows that these problems largely can be overcome by (1) agitating the constituents of the drilling fluid more vigorously, (2) maintaining a fairly constant temperature, and(3) Protecting the fluid from evaporation. When these steps are followed, the fluid properties approach asymptotic values that do not change by prolonged or accelerated agitation or by aging for a month. The time required to reach asymptotic values or a stabilized state is from 2 to 6 hours and is a function of the mud composition. Introduction Preparation of drilling fluids in the laboratory to determine their suitability to meet specific drilling requirements or to serve as a base fluid to evaluate the effectiveness of thinners, dispersants or other additives normally begins with combining measured quantities of the constituents and stirring them for a short time in a low-speed mixer. This is done to obtain a uniform mixture and to hydrate clays. Then the fluid is further agitated in a higher-speed device (Hamilton Beach mixer or Waring blender) to disperse more thoroughly and clay particles The biggest obstacle in the laboratory investigation of drilling fluids has been the lack of a method of producing a mixture by which reproducible results of the measured properties could be obtained. Numerous investigators have encountered this difficulty. Prior to 1929, density was the only property of mud that customarily was measured. The use of Wyoming bentonite on a large scale after 1929 was mainly responsible for the development of more elaborate testing procedures and for the application of the principles of colloid chemistry to the drilling fluids. Ambrose and Loomis in 1931 were among the first to recognize the plastic flow characteristics of drilling fluids, although Bingham in 1916 had observed The same phenomenon with dilute clay suspensions. Marsh introduced the Marsh funnel for field testing in 1931. By this time, non-Newtonian characteristics of drilling fluids were established. The Stormer and MacMichael viscometers were used to study the rheological properties of the fluids. In the 1930's and early 1940's, the work conducted by several investigators contributed toward a better understanding of drilling fluids. In the mid 1930's, fluid-loss and the associated mud-cake-forming properties of drilling fluids were recognized as important to the behavior of these fluids. The other properties of drilling fluids, including gel strength, pH, and sand content soon were recognized. In 1937, API published its first recommended procedure for test methods. Since that time, these procedures have been revised periodically. The latest edition, RP-13B, was published in 1961 However, in spite of the recognized need for a method of mixing that provides drilling fluids with stabilized properties, no such method previously has been described. SPEJ P. 403

scholarly journals Coalescence Dynamics of Acoustically Levitated Droplets

Micromachines ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 343 ◽  
Author(s):  
Koji Hasegawa ◽  
Ayumu Watanabe ◽  
Akiko Kaneko ◽  
Yutaka Abe
Keyword(s):  
Sound Pressure ◽  
Phased Array ◽  
Phased Arrays ◽  
Industrial Applications ◽  
Acoustic Levitation ◽  
Droplet Dynamics ◽  
Levitated Droplets ◽  
Ultrasonic Phased Array ◽  
Velocity Information ◽  
The Impact

The contactless coalescence of a droplet is of paramount importance for physical and industrial applications. This paper describes a coalescence method to be used mid-air via acoustic levitation using an ultrasonic phased array system. Acoustic levitation using ultrasonic phased arrays provides promising lab-on-a-drop applications, such as transportation, coalescence, mixing, separation, evaporation, and extraction in a continuous operation. The mechanism of droplet coalescence in mid-air may be better understood by experimentally and numerically exploring the droplet dynamics immediately before the coalescence. In this study, water droplets were experimentally levitated, transported, and coalesced by controlled acoustic fields. We observed that the edges of droplets deformed and attracted each other immediately before the coalescence. Through image processing, the radii of curvature of the droplets were quantified and the pressure difference between the inside and outside a droplet was simulated to obtain the pressure and velocity information on the droplet’s surface. The results revealed that the sound pressure acting on the droplet clearly decreased before the impact of the droplets. This pressure on the droplets was quantitatively analyzed from the experimental data. Our experimental and numerical results provide deeper physical insights into contactless droplet manipulation for futuristic lab-on-a-drop applications.

scholarly journals RISK MANAGEMENT SYSTEM ON RAILWAY TRANSPORT

2021 ◽  
Author(s):  
Olena Tsvirko ◽  
Denys Krylov
Keyword(s):  
Risk Management ◽  
Management System ◽  
Large Scale ◽  
Structural Reform ◽  
Railway Transport ◽  
Short Term ◽  
Risk Assessment Models ◽  
Risk Management System ◽  
Risk Management Process ◽  
Iso 31000

The article considers the concept of "risk in railway transport", identifies the types of risks that exist in the railway transport of Ukraine; determined that the processes of transformation of economic relations in Ukraine require the deepening of theoretical and practical developments in risk management in the field of railway transport; the risk management process according to the ISO 31000: 2018 standard is given; according to the implemented Strategy and Policy of JSC "Ukrzaliznytsia" the main tasks of the risk management system are defined and the risk map of JSC "Ukrzaliznytsia" is developed; The results of the structural reform of railway transport were insufficient to create effective sources of development in the short term, which will ensure large-scale attraction of funds for the development of the industry and its modernization. The results of the structural reform of railway transport were insufficient to create effective sources of development in the short term, which will ensure large-scale attraction of funds for the development of the industry and its modernization. Many types of risks that need to be assessed, as well as different purposes of assessing the same type of risk (for the purposes of state supervision and company purposes) provide JSC "Ukrzaliznytsia" a real challenge in terms of building risk assessment models. The task of applying the method of assessing a specific type of risk is significantly different from the task of building a methodology for assessing the risks of a large company. In solving this problem, it is important to keep in mind that a method successfully applied in one area may be completely ineffective in another. Risk classification of JSC "Ukrzaliznytsia" should be carried out taking into account the existing management structure, as well as the tasks to be solved at each level of management; the effect of the risk management system should be synergistic, each element of each level of management should be effective: from the structural unit at the linear level to the department of the corporate level of management. Currently, for the company's internal purposes, several dozen risks have been formulated related to various areas of life of JSC UZ: from financial activities to locomotive maintenance and innovative development.

scholarly journals On development of a technique for estimating structural dynamics and strength of modular phased array

2017 ◽  
pp. 75-82
Author(s):  
V. G. Lisovskiy ◽  
E. N. Khmelnitskiy ◽  
A. V. Kuzmicheva
Keyword(s):  
Structural Dynamics ◽  
Phased Array ◽  
Phased Arrays ◽  
Dynamic Environment ◽  
Vibration Acceleration ◽  
Transmission Coefficients ◽  
Mechanical Factors ◽  
Strain Stress ◽  
The Individual ◽  
Stiffening Effect

The purpose of the study was to develop a method of computational and experimental analysis to reduce the dimension of the problem, which makes it possible to simplify and accelerate the strength calculations. When using the method, one can take into account the stiffening effect of the carrier object, where the product will be installed, determine the transmission coefficients of vibration acceleration from the base of the structure to the individual units of the equipment to assess their strength and stability under the influence of mechanical factors. Moreover, the method allows for the strain-stress state analysis using the dynamic environment coefficients. Currently, the developed method is used in the design of several promising projects using modular phased arrays, both sea and land-based

scholarly journals Radiation Research with Pigeonpeas (Cajanus cajan): Results on X3 and X4 Generations

1969 ◽  
Vol 46 (1) ◽  
pp. 34-42
Author(s):  
R. Abrams ◽  
J. Vélez-Fortuño
Keyword(s):  
Commercial Variety ◽  
Yield Increase ◽  
Testing Procedures ◽  
Standard Testing ◽  
Parent Variety ◽  
Mutant Strains ◽  
Γ Rays ◽  
Mutant Lines ◽  
Radiation Research ◽  
Better Than

A number of agronomically desirable mutant strains of pigeonpeas were isolated from seed of Kaki variety irradiated with γ rays and neutrons. Some were earlier than the parent variety while others were later in date of flowering during the X3 and X4 generations tests. Many of the mutant lines also yielded better than the parent variety and late commercial variety Saragateado. The results from the X3 and X4 generations indicate that 1, Irradiation resulted in mutations which conditioned a yield increase in selected pigeonpea lines; 2, mutation effect in yield was large enough to be detected with the standard testing procedures; and 3, it is possible to fix some of the genetic variability in the irradiated families by repeated single plant selections, as in the case of flowering date.

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