Univ. Prof. Dr. Ing.

Bergs, Thomas

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Now showing 1 - 10 of 19
  • Publication
    Methodology for the self-optimizing determination of additive manufacturing process eligibility and optimization potentials in toolmaking
    ( 2022)
    Dannen, Tammo
    ;
    Schindele, Benedikt
    ;
    Prümmer, Marcel
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    Additive Manufacturing (AM) of metallic workpieces faces a continuously rising technological relevance and market size. Producing complex or highly strained unique workpieces is a significant field of application, making AM highly relevant for tool components. Its successful economic application requires systematic workpiece based decisions and optimizations. Considering geometric and technological requirements as well as the necessary post-processing makes deciding effortful and requires in-depth knowledge. As design is usually adjusted to established manufacturing, associated technological and strategic potentials are often neglected. To embed AM in a future proof industrial environment, software-based self-learning tools are necessary. Integrated into production planning, they enable companies to unlock the potentials of AM efficiently. This paper presents an appropriate methodology for the analysis of process-specific AM-eligibility and optimization potential, added up by concrete optimization proposals. For an integrated workpiece characterization, proven methods are enlarged by tooling-specific figures. The first stage of the approach specifies the model's initialization. A learning set of tooling components is described using the developed key figure system. Based on this, a set of applicable rules for workpiece-specific result determination is generated through clustering and expert evaluation. Within the following application stage, strategic orientation is quantified and workpieces of interest are described using the developed key figures. Subsequently, the retrieved information is used for automatically generating specific recommendations relying on the generated ruleset of stage one. Finally, actual experiences regarding the recommendations are gathered within stage three. Statistic learning transfers those to the generated ruleset leading to a continuously deepening knowledge base. This process enables a steady improvement in output quality.
  • Publication
    Nutzbarmachung von heterogenen Metadaten
    ( 2021)
    Bergs, Thomas
    ;
    Weber, Sebastian
    ;
    Stepien, Grzegorz
    ;
    Henrichs, Oliver
    ;
    Prümmer, Marcel
    ;
    Arntz, Kristian
    Das PyIntegrationNet demonstriert den Mehrwert, den eine strukturierte, modulare und dadurch einfach um neue Datenquellen erweiterbare Datenintegrationsmethodik liefern kann. Hierbei können selbst vergleichsweise einfach strukturierte, täglich anfallende Daten wie XML oder Logdateien Zusammenhänge offenbaren und quantifizieren, die, wie am Beispiel der Senkerosion gezeigt, zur Vorhersage relevanter Größen wie der Hauptzeit genutzt werden können und dadurch die Prognosefähigkeit einer Technologie zu verbessern. Mit steigender Datenverfügbarkeit und der Integration neuer Datenquellen ist zu erwarten, dass sich die Genauigkeit solcher Vorhersagen in Zukunft noch weiter steigern lässt und prozessübergreifende Optimierungspotentiale gehoben werden können.
  • Publication
    Development of handling system concepts for additive process chains with Laser Powder Bed Fusion (L-PBF)
    ( 2021)
    Horstkotte, Rainer
    ;
    Heinrich, Florian
    ;
    Prümmer, Marcel
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    Laser Powder Bed Fusion (L-PBF) is an additive manufacturing (AM) technology that enables the production of highly complex and individualized metal components. Since these components need post-processing, L-PBF is usually utilized within a manufacturing process chain. The automation of this process chain is a crucial step towards the industrialization of L-PBF. This paper presents a methodology for the conceptual design of handling systems for the automated handling of L-PBF components. It includes the selection of gripping and clamping devices, robots and other peripheral systems. Restrictions that arise from the complexity of the components and the technologies are considered.
  • Publication
    Generation and evaluation of automation concepts of additive process chains with Laser Powder Bed Fusion (L-PBF)
    ( 2021)
    Horstkotte, Rainer
    ;
    Heinrich, Florian
    ;
    Prümmer, Marcel
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    Laser Powder Bed Fusion (L-PBF) is an additive manufacturing (AM) technology that plays a major role in the production of mass customized metal components and products. A significant disadvantage of AM is the required post-processing of the additive manufactured parts, which is necessary to remove auxiliary structures, separate the workpieces from the substrate plate and achieve high precision as well as low surface roughness. Automation of these post-processes is a crucial factor for increasing productivity and thus for further industrialization of L-PBF. This paper presents a methodology to model and evaluate the manufacturing process chain of post-processing with regard to automation. For this purpose, a uniform notation is introduced to model the sequence of manufacturing processes and handling operations. The notation allows the representation of different automation concepts and integrates typical post-processes for L-PBF manufactured parts. A reference scale is used to evaluate different concepts with regard to their level of automation. The focus on lead time estimation enables the methodology to generate and evaluate different automation concepts.
  • Publication
    Determination of the Level of Automation for Additive Manufacturing Process Chains
    ( 2021)
    Horstkotte, Rainer
    ;
    Bruning, Benedikt
    ;
    Prümmer, Marcel
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    Industrial manufacturing is confronted with increased cost pressure due to international competition. The use of automation solutions can help to optimally exploit existing potentials and react to market competitors. In particular, increased productivity and shorter cycle times lead to reduced costs and increased capabilities. New manufacturing technologies can also help to achieve an advantage over market competitors. In recent years, additive manufacturing technologies in particular have gained in importance. Laser Powder Bed Fusion (L-PBF) is an additive manufacturing (AM) technology that enables the production of highly complex and individualized metal components. A significant disadvantage of L-PBF is the required post-processing of additive manufactured parts, which is necessary to remove auxiliary structures, separate the workpieces from the substrate plate and obtain high precision as well as low surface roughness. Automation of these post-processes is a crucial factor for increasing productivity and thus for further industrialization of L-PBF. In order to exploit this potential optimally, the level of automation has to be determined. In this paper, a methodology is presented that enables the determination of the level of automation for the additive process chain with L-BPF. The focus is on evaluating the level of automation of individual manufacturing technologies due to consideration of technology-specific requirements and characteristics. The scope of the analysis is not limited to technologies; handling processes are also taken into account. A differentiated e valuation of the level of automation is enabled by the definition of technology-specific and cross-technology sub-tasks.
  • Publication
    Design model for a value chain-oriented quality management in global tooling
    ( 2020)
    Bergs, Thomas
    ;
    Prümmer, Marcel
    ;
    Lürken, Christian
    ;
    Arntz, Kristian
    The globalization of production has current effects on the tooling industry. Customer proximity, fast reaction times and a worldwide service range are significant selling propositions for market positioning of a toolmaking company. Nevertheless, high quality standards are indispensable to distinguish from the international competition. The developed quality management model includes three design modules giving different approaches for quality improvement in tool manufacturing. Additionally, digitalization solutions to support the implementation of quality gates in single batch production are presented. Furthermore, five main target aspects have been developed for a framework of a value chain-oriented QM model for global producing tooling companies.
  • Publication
    Durchgängige Bearbeitung von 3D-gedruckten Metallteilen
    ( 2020)
    Wollbrink, Moritz
    ;
    Maslo, Semir
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    Der Fertigungsanteil der additiven Fertigung (AM) und besonders des pulverbettbasierten Laserstrahlschmelzens (L-PBF) nimmt in der industriellen Anwendung weiter zu. Allein mit AM lassen sich jedoch oft keine engen Maßtoleranzen oder geringen Oberflächenrauheiten erzielen. Daher muss eine Prozesskette generiert werden, die die additive Fertigung mit weiteren Bearbeitungstechnologien kombiniert. Um einen kontinuierlichen Werkstückfluss als Basis für die weitere Industrialisierung von L-PBF zu erreichen, wird ein neuartiges Substratplattensystem sowie dessen Anwendung in L-PBF-Maschinen und bei der Weiterbearbeitung vorgestellt. Das Substratplattensystem besteht aus einem Nullpunkt-Spannsystem und matrixartig angeordneten Verbindungsstiften, welche die werkstückseitige Verbindung sehr flexibel ermöglichen.
  • Publication
    Pulsed Laser Influence on Temperature Distribution during Dual Beam Laser Metal Deposition
    ( 2020)
    Gipperich, Marius
    ;
    Riepe, Jan
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    Wire-based Laser Metal Deposition (LMD-w) is a suitable manufacturing technology for a wide range of applications such as repairing, coating, or additive manufacturing. Employing a pulsed wave (pw) laser additionally to the continuous wave (cw) process laser has several positive effects on the LMD process stability. The pw-plasma has an influence on the cw-absorption and thus the temperature distribution in the workpiece. In this article, several experiments are described aiming to characterize the heat input during dual beam LMD. In the first setup, small aluminum and steel disks are heated up either by only cw or by combined cw and pw radiation. The absorbed energy is then determined by dropping the samples into water at ambient temperature and measuring the waters temperature rise. I n a second experiment, the temperature distribution in the deposition zone under real process conditions is examined by two-color pyrometer measurements. According to the results, the pw plasma leads to an increase of the effective absorption coeffcient by more than 20%. The aim of this work is to achieve a deeper understanding of the physical phenomena acting during dual beam LMD and to deploy them selectively for a better and more flexible process control.
  • Publication
    Clamping and substrate plate system for continuous additive build-up and post-processing of metal parts
    ( 2020)
    Wollbrink, Moritz
    ;
    Maslo, Semir
    ;
    Zimmer, Daniel
    ;
    Abbas, Karim
    ;
    Arntz, Kristian
    ;
    Bergs, Thomas
    The manufacturing share of laser powder bed fusion (L-PBF) increases in industrial application, but still many process steps are manually operated. Additionally, it is not possible to achieve tight dimensional tolerances or low surfaces roughness. Hence, a process chain has to be set up to combine additive manufacturing (AM) with further machining technologies. To achieve a continuous workpiece flow as basis for further industrialization of L-PBF, the paper presents a novel substrate system and its application on L-PBF machines and post-processing. The substrate system consists of a zero-point clamping system and a matrix-like interface of contact pins to be substantially connected to the workpiece within the L-PBF process.
  • Publication
    Individuelle Prozessketten im Werkzeugbau durch daten- und modellbasierte Prognosen
    ( 2020)
    Bergs, Thomas
    ;
    Arntz, Kristian
    ;
    Prümmer, Marcel
    ;
    Wilms, Marcel
    Konnte sich der Werkzeugbau in der Vergangenheit durch die eigene Innovationskraft vom globalen Markt differenzieren, so muss er sich heutzutage durch die Effizienzsteigerung in der Fertigung und die Senkung der Produktionskosten vom Markt abgrenzen. Der heterogene Einsatz verschiedenster Fertigungstechnologien erzeugt einen hohen Planungsaufwand in der Unikatfertigung und erfordert technologieübergreifendes Prozess-verständnis. Auf Basis dieser Komplexität resultieren starke Abweichungen der prognostizierten und tatsächlichen Bearbeitungszeiten, sowohl auf Einzeltechnologieebene als auch technologieübergreifend. Dies hat zur Folge, dass deutliche Potenziale in der Fertigung liegen gelassen werden. Ein möglicher Lösungsansatz diese Potenziale zu nutzen, liegt in der Implementierung von individuellen und adaptiven Prozessketten, sodass bei Störungen wie bspw. einem Maschinenausfall oder Eilaufträgen, auch technologieüber-greifend umgeplant werden kann. Zur Integration von individuellen Prozessketten müssen jedoch einige Herausforderungen überwunden werden, wie bspw. die Erhöhung der Prognosefähigkeit und die Klassifizierung von Bauteilen in der Unikatfertigung. Durch die Kopplung von modell- und datenbasierten Methoden kann die Anzahl an benötigten Daten reduziert und die Prognosefähigkeit gesteigert werden. Darüber hinaus ist die Maschinendatenverfügbarkeit und -verarbeitung entscheidend um weiteres Prozesswissen für die Entscheidungsfindung und Arbeitsplanerstellung zu generieren.