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A Measurement Method for Characterising Micro Lead on Ground Shaft Surfaces Herausgeber: Prof ISBN: 978-3-95974-047-0 Philipp Arnecke ISSN: 2365-9742 Kurzfassung Bei der Herstellung von Wellenoberflächen als Gegenlaufflächen für Radialwellendichtringe in -dy namischen Dichtsystemen können Strukturen auftreten, die Einfluss auf die Funktion des Dicht- systems haben können. Diese Strukturen werden als Drall bezeichnet und können entsprechend ihrer Ausprägung und Entstehung in die Drallarten Makro- und Mikrodrall eingeteilt werden. Im A measurement method for characterising Optimalfall wird Drall bereits während der Herstellung vermieden, zumindest soll er aber erkannt micro lead on ground shaft surfaces und bezüglich seiner Ausprägung an Hand von Parametern quantifiziert werden. Während Messme- thoden und Verfahren zum Nachweis von Makrodrall existieren, wird in dieser Arbeit eine Methode zur Charakterisierung von Mikrodrall, also der Hauptrichtung der Bearbeitungsstruktur bezogen auf die Umfangsrichtung, beschrieben. Aus der Definition von Mikrodrall folgt direkt, dass sowohl die Umfangs- als auch die Bearbeitungs- richtung hochgenau erfasst werden müssen. Zu diesem Zweck werden geeignete Messsysteme und zugehörige Kalibrierverfahren beschrieben, welche neben der Messung der Wellenoberfläche die Kalibrierung der Umfangsrichtung mit hoher Genauigkeit und niedriger Unsicherheit ermöglichen. Auf Basis dieser flächenhaften Messungen wird ein Verfahren zur Ermittlung der Texturrichtung, dem die Radontransformation zu Grunde liegt, vorgestellt und parametrisiert. Mit der Ermittlung der Texturrichtung und der Kalibrierung der Achslage können damit beide Anforderungen an die Messmethode zur Mikrodrallmessung an geschliffenen Wellenoberflächen erfüllt werden. Abstract The detection and characterisation of undesired lead structures on shaft surfaces is a concern in production and quality control of rotary shaft lip-type sealing systems. The potential lead struc- tures are generally divided into macro and micro lead based on their characteristics and formation. Macro lead measurement methods exist and are widely applied. This work describes a method to characterise micro lead on ground shaft surfaces. Micro lead is known as the deviation of main orientation of the ground micro texture from circumferential direction. Assessing the orientation of microscopic structures with arc minute accuracy with regard to cir- cumferential direction requires exact knowledge of both the shaft’s orientation and the direction of surface texture. The shaft’s circumferential direction is found by calibration. Measuring systems and calibration procedures capable of calibrating shaft axis orientation with high accuracy and low un- shaft ground on lead surfaces micro method forA measurement characterising certainty are described. The measuring systems employ areal-topographic measuring instruments suited for evaluating texture orientation. A dedicated evaluation scheme for texture orientation is Berichte aus dem Lehrstuhl für Messtechnik und Sensorik based on the Radon transform of these topographies and parametrised for the application. Com- Band 4 bining the calibration of circumferential direction with the evaluation of texture orientation the Herausgeber: Prof. Dr.-Ing. Jörg Seewig method enables the measurement of micro lead on ground shaft surfaces. P. Arnecke Philipp Arnecke A measurement method for characterising micro lead on ground shaft surfaces Berichte aus dem Lehrstuhl für Messtechnik und Sensorik Band 4 Herausgeber: Prof. Dr.-Ing. Jörg Seewig Bibliografische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.d-nb.de abrufbar. Berichte aus dem Lehrstuhl für Messtechnik und Sensorik - Band 4 Herausgeber: Prof. Dr.-Ing. Jörg Seewig Lehrstuhl für Messtechnik und Sensorik Fachbereich Maschinenbau und Verfahrenstechnik Technische Universität Kaiserslautern Gottlieb-Daimler-Straße 67663 Kaiserslautern Verfasser: Philipp Arnecke Verlag: Technische Universität Kaiserslautern Druck: Technische Universität Kaiserslautern Hauptabteilung 5 | Abteilung 5.6 Foto-Repro-Druck D-386 © Philipp Arnecke · Kaiserslautern 2017 Alle Rechte vorbehalten, auch das des auszugsweisen Nachdrucks, der auszugsweisen oder vollständigen Wiedergabe (Photographie, Mikroskopie), der Speicherung in Datenverarbeitungsanlagen und das der Übersetzung. Als Manuskript gedruckt. Printed in Germany. ISSN 2365-9742 ISBN 978-3-95974-047-0 Kurzfassung Bei der Herstellung von Wellenoberflächen als Gegenlaufflächen für Radialwellendicht- ringe in dynamischen Dichtsystemen können Strukturen auftreten, die Einfluss auf die Funktion des Dichtsystems haben können. Diese Strukturen werden als Drall bezeich- net und können entsprechend ihrer Ausprägung und Entstehung in die Drallarten Makro- und Mikrodrall eingeteilt werden. Im Optimalfall wird Drall bereits während der Herstel- lung vermieden, zumindest soll er aber erkannt und bezüglich seiner Ausprägung an Hand von Parametern quantifiziert werden. Während Messmethoden und Verfahren zum Nachweis von Makrodrall existieren, wird in dieser Arbeit eine Methode zur Cha- rakterisierung von Mikrodrall, also der Hauptrichtung der Bearbeitungsstruktur bezo- gen auf die Umfangsrichtung, beschrieben. Aus der Definition von Mikrodrall folgt di- rekt, dass sowohl die Umfangs- als auch die Bearbeitungsrichtung hochgenau erfasst werden müssen. Zu diesem Zweck werden geeignete Messsysteme und zugehörige Kalibrierverfahren beschrieben, welche neben der Messung der Wellenoberfläche die Kalibrierung der Umfangsrichtung mit hoher Genauigkeit und niedriger Unsicherheit ermöglichen. Auf Basis dieser flächenhaften Messungen wird ein Verfahren zur Ermitt- lung der Texturrichtung, dem die Radontransformation zu Grunde liegt, vorgestellt und parametrisiert. Mit der Ermittlung der Texturrichtung und der Kalibrierung der Achsla- ge können damit beide Anforderungen an die Messmethode zur Mikrodrallmessung an geschliffenen Wellenoberflächen erfüllt werden. Abstract The detection and characterisation of undesired lead structures on shaft surfaces is a concern in production and quality control of rotary shaft lip-type sealing systems. The potential lead structures are generally divided into macro and micro lead based on their characteristics and formation. Macro lead measurement methods exist and are widely applied. This work describes a method to characterise micro lead on ground shaft surfaces. Micro lead is known as the deviation of main orientation of the ground micro texture from circumferential direction. Assessing the orientation of microscopic structures with arc minute accuracy with regard to circumferential direction requires exact knowledge of both the shaft’s orientation and the direction of surface texture. The shaft’s circumferential direction is found by calibration. Measuring systems and calibration procedures capable of calibrating shaft axis orientation with high accuracy and low uncertainty are described. The measuring systems employ areal-topographic measuring instruments suited for evaluating texture orientation. A dedicated evaluation scheme for texture orientation is based on the Radon transform of these topographies and parametrised for the application. Combining the calibration of circumferential dir- ection with the evaluation of texture orientation the method enables the measurement of micro lead on ground shaft surfaces. A measurement method for characterising micro lead on ground shaft surfaces Vom Fachbereich Maschinenbau und Verfahrenstechnik der Technischen Universität Kaiserslautern zur Verleihung des akademischen Grades Doktor-Ingenieur (Dr.-Ing.) genehmigte Dissertation vorgelegt von Dipl.-Ing. Philipp Arnecke aus Würzburg Kaiserslautern 2017 D 386 Dekan: Prof. Dr.-Ing. Jörg Seewig Vorsitzender: Prof. Dr.-Ing. Bernd Sauer Berichterstatter: Prof. Dr.-Ing. Jörg Seewig Prof. Dr.-Ing. habil. Peter Lehmann Tag der mündlichen Prüfung: 22. August 2016 Preface and Acknowledgements The presented thesis is the outcome of my time as research assistant at the Institute for Measurement and Sensor Technology at the University of Kaiserslautern. Funding was received from the Stiftung Rheinland-Pfalz für Innovation through research grant 987 ”Anwenderorientierte Charakterisierung von Mikrodrall auf Basis optischer Mess- einrichtungen”. The completion of this thesis would not have been possible without the support from my colleagues, friends and family. First, I would like to cordially thank my doctoral adviser Mr Prof. Dr.-Ing. Jörg Seewig for the trust he placed in me over the years first as student assistant and then as re- search assistant. I benefited from the unconstrained atmosphere at his institute and the scientific freedom to follow own ideas together with his very competent advice and suggestions at the right places. All of this together with his personal straightforward and humane attitude had their share in succeeding the work. I would also like to thank both members of the board of examiners, Mr Prof. Dr.-Ing. habil. Peter Lehmann and Mr Prof. Dr.-Ing. Bernd Sauer, for the interest in my work, the rewarding discussions and the overall smooth procedure. The great colleagues at MTS contributed a lot to the work. Not only as great part- ners in research related discussions with many valuable suggestions drawn from their vast experience in metrology and related subjects but also in off-research activities. I would especially like to highlight the enriching contributions of student
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