Third International Symposium on Magnetic Suspension Technology

In order to examine the state of technology of all areas of magnetic suspension and to review recent developments in sensors, controls, superconducting magnet technology, and design/implementation practices, the Third International Symposium on Magnetic Suspension Technology was held at the Holiday Inn Capital Plaza in Tallahassee, Florida on 13-15 Dec. 1995. The symposium included 19 sessions in which a total of 55 papers were presented. The technical sessions covered the areas of bearings, superconductivity, vibration isolation, maglev, controls, space applications, general applications, bearing/actuator design, modeling, precision applications, electromagnetic launch and hypersonic maglev, applications of superconductivity, and sensors

A model development for reconstruction of three-dimensional defects based on MFL signals

Corrosion has been statistically placed as the primary cause for pipeline failures well beyond other factors. The inability to accurately size corrosion defects located in pipelines can result in erroneous integrity strategies with fatal consequences, even when appropriate inspection processes have been conducted. Underestimation or overestimation of the defect size causes on one hand pipeline failures and on the other unnecessary assessments. Several strategies for defect sizing based on MFL signals have been developed in recent years. However, the industry still urges for reliability improvements. The current thesis develops a model based on calibration curves for the reconstruction of defects, based on MFL signals. A thorough study of different parameters involved allows for the understanding of the relationships between defect dimensions and MFL signal features. The methodology of this research includes theoretical, numerical and experimental assessments resulting in the development of a reliable three-dimensional model. Calibration curves are reported for inner as well as for outer defect configuration. Such curves permit the accurate establishment of the defect length and depth by means of the signal duration and amplitude. The results of this study for a single defect can be further implemented in order to investigate the superposition of MFL signals coming from adjacent defects. The MFL signal superposition is demonstrated through simulations and experiments.Nach der Statistik ist Korrosion, neben anderen Faktoren, die primäre Ursache für Rohrleitungsversagen. Die Unfähigkeit, Korrosionsfehler in Rohrleitungen genau zu dimensionieren, kann zu fehlerhaften Integritätsstrategien mit fatalen Folgen führen, selbst wenn geeignete Prüfprozesse angewendet werden. Eine Unterschätzung oder Überschätzung der Fehlergröße führt einerseits zu Pipelineversagen und andererseits zu unnötigen Untersuchungen. In den letzten Jahren wurden verschiedene Strategien zur Fehlergrößenbestimmung basierend auf Signalen des magnetischen Streuflusses entwickelt. Die Industrie drängt jedoch weiterhin auf eine Verbesserung der Zuverlässigkeit durch diese Technik. In der vorliegenden Arbeit werden Kalibrierkurven für die Rekonstruktion von Fehlstellen basierend auf Signalen des magnetischen Streuflusses beschrieben. Eine gründliche Untersuchung der verschiedenen Einflussparameter ermöglicht die Beziehungen zwischen den Dimensionen der Fehlstellen und Signalmerkmalen des magnetischen Streuflusses zu verstehen. Die Methodik dieser Forschung umfasst theoretische, numerische und experimentelle Bewertungen, die zur Entwicklung eines zuverlässigen dreidimensionalen Modells führen. Kalibrierkurven werden sowohl für Innen- als auch für Außenfehler angegeben. Solche Kurven ermöglichen die genaue Ermittlung der Fehlstellenlänge und -tiefe anhand der Signallänge und -amplitude. Die Ergebnisse, die in dieser Studie für Einzelfehler gewonnen wurden können verwendet werden, um Untersuchungen an benachbarten Fehlstellen durchzuführen, bei denen sich die Signale des magnetischen Streuflusses überlagern

Design of the Annular Suspension and Pointing System (ASPS) (including design addendum)

The Annular Suspension and Pointing System is an experiment pointing mount designed for extremely precise 3 axis orientation of shuttle experiments. It utilizes actively controlled magnetic bearing to provide noncontacting vernier pointing and translational isolation of the experiment. The design of the system is presented and analyzed

Surveyor landing radar test program review Final report

Test program evaluation and modifications for Surveyor radar altimeter and Doppler velocity sensor syste

Interim Design Report

The International Design Study for the Neutrino Factory (the IDS-NF) was established by the community at the ninth "International Workshop on Neutrino Factories, super-beams, and beta- beams" which was held in Okayama in August 2007. The IDS-NF mandate is to deliver the Reference Design Report (RDR) for the facility on the timescale of 2012/13. In addition, the mandate for the study [3] requires an Interim Design Report to be delivered midway through the project as a step on the way to the RDR. This document, the IDR, has two functions: it marks the point in the IDS-NF at which the emphasis turns to the engineering studies required to deliver the RDR and it documents baseline concepts for the accelerator complex, the neutrino detectors, and the instrumentation systems. The IDS-NF is, in essence, a site-independent study. Example sites, CERN, FNAL, and RAL, have been identified to allow site-specific issues to be addressed in the cost analysis that will be presented in the RDR. The choice of example sites should not be interpreted as implying a preferred choice of site for the facility

Halogen occultation experiment intergrated test plan

The test program plan is presented for the Halogen Occultation Experiment (HALOE) instrument, which is being developed in-house at the Langley Research Center for the Upper Atmosphere Research Satellite (UARS). This comprehensive test program was developed to demonstrate that the HALOE instrument meets its performance requirements and maintains integrity through UARS flight environments. Each component, subsystem, and system level test is described in sufficient detail to allow development of the necessary test setups and test procedures. Additionally, the management system for implementing this test program is given. The HALOE instrument is a gas correlation radiometer that measures vertical distribution of eight upper atmospheric constituents: O3, HC1, HF, NO, CH4, H2O, NO2, and CO2

Novel Approaches for Nondestructive Testing and Evaluation

Nondestructive testing and evaluation (NDT&E) is one of the most important techniques for determining the quality and safety of materials, components, devices, and structures. NDT&E technologies include ultrasonic testing (UT), magnetic particle testing (MT), magnetic flux leakage testing (MFLT), eddy current testing (ECT), radiation testing (RT), penetrant testing (PT), and visual testing (VT), and these are widely used throughout the modern industry. However, some NDT processes, such as those for cleaning specimens and removing paint, cause environmental pollution and must only be considered in limited environments (time, space, and sensor selection). Thus, NDT&E is classified as a typical 3D (dirty, dangerous, and difficult) job. In addition, NDT operators judge the presence of damage based on experience and subjective judgment, so in some cases, a flaw may not be detected during the test. Therefore, to obtain clearer test results, a means for the operator to determine flaws more easily should be provided. In addition, the test results should be organized systemically in order to identify the cause of the abnormality in the test specimen and to identify the progress of the damage quantitatively

Current deflection NDE for pipe inspection and monitoring

The detection of corrosion on insulated and/or coated pipes in the oil and gas industry remains a challenge. Routine inspection, which is commonly achieved with in-line tools known as "pigs", is not possible where there is any risk of the pig becoming stuck. There are thousands of kilometers of pipe worldwide deemed ``unpiggable'' whose safety must be ensured using Non-Destructive Evaluation (NDE) external to the pipe if potentially catastrophic failure is to be avoided. Many NDE techniques lack sufficient sensitivity due to the coating thickness producing a high standoff distance between the pipe and the sensor and therefore require costly and time-consuming removal of the coating. A method capable of detecting and/or monitoring of defects (e.g. one-third-wall depth corrosion) while leaving the insulation/coating intact would be highly attractive. This thesis documents the development of a technique in which a low-frequency AC current is directly injected into the pipe at distant locations, and perturbations in the magnetic field caused by "current deflection" around defects are measured using solid-state magnetic sensors. Two methods of applying this novel technique were investigated. Firstly, scanning the sensors to measure perturbations in the field and screen for defects, and secondly, permanently installing sensors outside the pipe for Structural Health Monitoring (SHM). A Finite Element (FE) model has been developed and used to investigate the practical challenges that are faced by the technique and how these may be overcome. The sensitivity of the technique for defect detection by external pipe scanning in a practical scenario has then been evaluated using a model-assisted Probability of Detection (POD) framework that combines the measurements of the signal from an undamaged pipe with synthetic damage profiles and contributions from general corrosion and sensor misalignment. The results indicate that good performance is expected for damage detection by scanning above a typical insulation thickness with just a few amps of injected current. A similar framework has then been used to evaluate the sensitivity of the technique as an SHM solution which suggests excellent corrosion detection performance with the permanent installation of inexpensive magnetic sensors. The technique has potential advantages over competing methods in both scanning and monitoring modes and there are many opportunities for future development.Open Acces