Profit-Driven Methodology for Servo Press Motion Selection under Material Variability

Servo presses enable new types of forming motion profiles that can be used to stamp difficult materials, such as high strength steels. This paper presents an application of Bayesian statistics to intelligently select which motion profile maximizes the expected utility given the properties of the incoming material. Bayesian logistic regression was used in conjunction with expected utility to estimate manufacturing returns, which can be used to make informed process decisions. A use case is presented, which demonstrates that the Smart Forming Algorithm can increase expected returns by more than 20%.

Sheet Metal Forming Optimization Methodology for Servo Press Process Control Improvement

In sheet metal forming manufacturing operations the use of servo presses is gaining more interest due to the opportunity to improve process performance (quality, productivity, cost reduction, etc.). It is not yet clear how to proceed in the engineering process when this type of operating machine is used to achieve the maximum possible potential of this technology. Recently, several press builders have developed gap- and straight-sided metal forming presses adopting the mechanical servo-drive technology. The mechanical servo-drive press offers the flexibility of a hydraulic press with the speed, accuracy and reliability of a mechanical press. Servo drive presses give the opportunity to improve the productivity of process conditions and improve the quality of stamped parts. Forming simulation and numerical optimization can be useful tools to define beforehand the optimal process parameter set-up in terms of servo press downward curve properties. This is done by carrying out a sensitivity analysis of the forming parameters having influence on said curve. The authors have developed a numerical methodology able to analyze the influence factors, for comparison with the degrees of freedom made available by the usage of a servo press, in terms of stroke profile management, to obtain an optimized process parameters combination.

Auslegung von Servopressenantrieben/Design of Servo Press Powertrains

Die Auslegung des Antriebsstrangs einer Servopresse stellt einen komplexen Prozess dar. Aufgrund der konstruktiven Wechselwirkung der Komponenten ist dieser mit einer potenziell großen Anzahl von Iterationsstufen, häufig auch im Kontakt mit Zulieferern, verbunden. Im Beitrag wird ein Softwaretool vorgestellt, das den Entwicklungsprozess einer Servo- presse beschleunigt und variabler gestaltet. Im Rahmen des Vorhabens wurde neben einem parametrischen Motormodell ein variables mechanisches Modell eines Servopressen-Antriebsstrangs erstellt und validiert.   The design of a servo press drive is a complex process. Due to the interaction of the design components in the drive train, it is subject to a potentially large number of iteration stages, often also in contact with suppliers. This article presents a software tool that accelerates the development process of an electrical servo press drive. Within the presented research project, a parametric motor model and a mechanic model of a servo press powertrain were developed and validated.