Vernetzte Fertigung/Connected manufacturing - Considering the manufacturing history of sheet metal components when joining by forming

2020 ◽  
Vol 110 (10) ◽  
pp. 677-683
Author(s):  
Sebastian Wiesenmayer ◽  
Per Heyser ◽  
Thomas Nehls ◽  
Philipp Frey ◽  
Wilko Flügge ◽  
...  
Keyword(s):  
Sheet Metal ◽  
Initial State ◽  
Joining By Forming ◽  
History Of ◽  
Joint Quality ◽  
Manufacturing History

Die Herstellung von Blechbauteilen umfasst mehrere Schneid- und Umformoperationen, welche die resultierenden Bauteileigenschaften beeinflussen. Daher weichen die Eigenschaften vom Ausgangszustand des Halbzeugs ab, was bei der Auslegung von Clinchverbindungen berücksichtigt werden muss. Durch die Vernetzung der Einzelverfahren auf Basis der Prozessdaten werden ein Vorgehen zur Ermittlung der Halbzeugeigenschaften beim Scherschneiden und die Auswirkungen auf die Verbindungsqualität beim Clinchen aufgezeigt.   Sheet metal components are manufactured in various cutting and forming operations influencing the resulting properties of the parts. As these properties differ from the initial state of the semi-finished products, they have to be considered in the design of clinched joints. By connecting individual processes, this paper presents an approach for determining the properties of semi-finished parts in shear-cutting operations as well as their effects on the joint quality in clinching.

Multi-Scale Virtual Reality of Sintering

2007 ◽  
Vol 534-536 ◽  
pp. 573-576
Author(s):  
Eugene Olevsky
Keyword(s):  
Global Scale ◽  
Initial State ◽  
Model Framework ◽  
Time Step ◽  
Computational Framework ◽  
Multi Scale ◽  
Scale Modeling ◽  
History Of ◽  
On Line ◽  
Damage Criteria

The directions of further developments in the modeling of sintering are pointed out, including multi-scale modeling of sintering, on-line sintering damage criteria, particle agglomeration, sintering with phase transformations. A true multi-scale approach is applied for the development of a new meso-macro methodology for modeling of sintering. The developed macroscopic level computational framework envelopes the mesoscopic simulators. No closed forms of constitutive relationships are assumed for the parameters of the material. When a time-step of the calculations is finished for one macroscopic element, the mesostructures of the next element are restored from the initial state according to the history of loading. The model framework is able to predict the final dimensions of the sintered specimen on a global scale and identify the granular structure in any localized area for prediction of the material properties.

The Effect of the Initial Stress and Strain State in Sheet Metals on the Roller Levelling Process

2015 ◽  
Vol 651-653 ◽  
pp. 1023-1028 ◽  
Author(s):  
Markus Grüber ◽  
Marius Oligschläger ◽  
Gerhard Hirt
Keyword(s):  
Process Control ◽  
Initial Stress ◽  
Sheet Metal ◽  
Process Parameters ◽  
Kinematic Hardening ◽  
Sheet Material ◽  
Stress And Strain ◽  
Fe Model ◽  
Sheet Metals ◽  
Initial State

Due to increasing requirements regarding the flatness of sheet metals, the process of roller levelling is of particular importance. The process itself is influenced by a high number of parameters such as machine design, sheet dimension, and material properties. Therefore, it is desirable to provide an online process control to react on changes of those process parameters. One possible approach for the layout of a process control and the identification of reference values is the use of the Finite Element Method (FEM). Considering the alternate bending a sheet metal undergoes when passing through a roller leveller, kinematic hardening of the sheet material must be taken into account. Additionally, the initial stress and strain distribution of the sheet metal – e.g. induced by coiling – has an influence on the material behaviour and consequently on the process parameters. With respect to these effects, a coupled FE model, which accounts for the initial state of the sheet metal, is introduced. An inverse calculation of material parameters describing the behaviour under cyclic load conditions has been done for an aluminium alloy AA5005 and a mild steel DC01. Based on this numerical setup, the influence of the initial stress state in the pre-levelled sheet metal on the roller levelling process has been deduced. Accompanying experiments on a down-sized roller leveller were carried out for a validation of the numerical setup.

scholarly journals Optimización operativa de Aguas de Manizales S.A. ESP, a partir de la implementación del SIG [Operational optimization of Aguas de Manizales S.A. ESP, throughout implementing a GIS]

2010 ◽  
Author(s):  
Valentina Giraldo Fadul
Keyword(s):  
Drinking Water ◽  
Initial State ◽  
Water Utility ◽  
Utility Company ◽  
Sewage System ◽  
Gis Applications ◽  
Utility Companies ◽  
El Sistema ◽  
History Of ◽  
Potential Improvement

Resumen Desde el desarrollo de los Sistemas de Información Geográfica su aplicación se ha extendido a diversos campos como densidad poblacional, medio ambiente, transporte, agricultura, entre otros. El sector de Agua potable y alcantarillado no ha sido ajeno a las bondades que brinda un SIG para administrar de manera gráfica diferentes elementos de un sistema que poseen atributos, características y una posición geográfica relativa. Con el fin de analizar la utilidad y beneficios de la implementación de un Sistema de Información Geográfica en una empresa de este tipo, se ha querido estudiar la empresa Aguas de Manizales S.A. ESP organización reconocida en Colombia como modelo de gestión en el sector de agua potable y alcantarillado, considerando la forma como el SIG contribuyó en su fortalecimiento empresarial y examinando el comportamiento y mejora de algunos de los componentes del sistema más representativos, además de concluir sobre las aplicaciones del SIG que hoy en día son susceptibles de mejorar su aprovechamiento en la empresa. Este documento describe en primera instancia el sistema de acueducto y alcantarillado operado por la empresa con el fin de identificar los diferentes elementos que entraron a ser administrados con ayuda del Sistema de Información Geográfica. Hace una presentación del estado inicial de los componentes del sistema antes de la implementación del SIG desde el punto de vista técnico y comercial. Así mismo, muestra un análisis de la forma como la puesta en marcha del mismo contribuyó a alcanzar la optimización operativa actual, detallando finalmente los diferentes beneficios obtenidos por la empresa y las aplicaciones y utilidades del SIG que cuentan con un potencial de mejora de su uso en una empresa de acueducto y alcantarillado. Palabras ClaveSIG, acueducto, alcantarillado. Abstract Since their early development Geographic information Systems (GIS) applications have extended to different areas such population density, natural environment, transportation, agriculture, among others. Water utility companies have also implemented GIS to manage the elements of their business possessing the geographical relative location and attributes that characterize them. Aguas de Manizales S.A. ESP is a leading water utility company in the sector of drinking water and sewage system in Colombia. This document describe the process of implementing a GIS system within AGUAS considering the history of the system implementation, the contributions of GIS to AGUAs management structure and the areas susceptible of further implementation.This document describes the characteristics of drinking water and sewage system operated by AGUAS identifying the different elements to be managed by the GIS. I present the initial state of the components of the system before the GIS implementation from the technical and commercial viewpoint and the developments to reach the current operative optimization. Finally, I summarize the benefits obtained for the organization and the areas for potential improvement. KeywordsGIS, drinking water, sewage.

scholarly journals Rhino Orbital Cerebral Mucormycosis in settings of Covid-19 infection: A Case Series of Thirteen Patients

2022 ◽  
Author(s):  
Rajesh Verma ◽  
Rajarshi Chakraborty ◽  
Keerthiraj DB ◽  
Kingzang Wangda ◽  
Veerendra Verma ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Public Awareness ◽  
Tertiary Care ◽  
Case Series ◽  
Care Hospital ◽  
Imaging Features ◽  
Initial State ◽  
Northern India ◽  
History Of

Abstract Background Rhino-Orbital-Cerebral Mucormycosis (ROCM) is an important infectious disease encountered in huge number in this recent post-covid 19 era. An alteration in defence immune system during covid-19 illness, in the presence of uncontrolled hyperglycaemia has led to the new epidemic of ROCM especially in developing nations like India. Method This case series of thirteen patients illustrates the various clinical presentation, laboratorical parameters, imaging features and outcome of patients of ROCM admitted in a tertiary care hospital in Northern India. Result In our case series, a total of 13 newly diagnosed cases of Rhino-Orbital-Cerebral Mucormycosis were studied. History of covid-19 illness was observed in 7 cases (53.8%), use of steroid during Covid-19 illness was seen in 5 cases (38.5%), oxygen therapy was given in 4 cases (30.8%). Co-morbid state in the form of diabetes mellitus was present in 12 cases (92.3%) with mean duration 16.69 months with an important finding of 6 cases (46.2%) having new-onset diabetes; hypertension in present in 3 cases (23.1%). Magnetic resonance imaging of paranasal sinuses showed involvement of multiple sinuses in all the 13 cases(100%), including maxillary and ethmoidal sinuses, with frontal in 12 cases (92.3%), sphenoidal in 11 cases (84.6%), symmetric in 9 cases (69.2%), mastoiditis in 4 cases (30.8%), maxillary space involvement in 4 cases (30.8%), palatal involvement in 1 case (7.7%). Multi-speciality approach treatment was given in the liposomal amphotericin B therapy in all the patients along with thorough endo-nasal debridement done in all cases, transcutaneous retrobulbar amphotericin B in 6 cases (46.2%) with exenteration done in 7 patients (53.9%). At 3 months of follow-up, there was substantial clinical improvement in all the cases. Conclusion There should be definite emphasis on high suspicion of mucor clinically for early diagnosis and aggressive management at initial state of diagnosis for better outcome. The need for sustained proper glycemic control during covid 19 era along with judicious use of steroid and public awareness for early symptoms and manifestations of mucor can curb the magnitude of such potentially opportunistic epidemic to a substantial rate. The longer the infection remains undetected, the greater the devastation ROCM can impose, of which blindness is an important hazard.

Modeling of Anisotropic Deformation in Superplastic Sheet Metal Stretching

2005 ◽  
Vol 127 (1) ◽  
pp. 159-164 ◽  
Author(s):  
Fadi K. Abu-Farha ◽  
Marwan K. Khraisheh
Keyword(s):  
Sheet Metal ◽  
Microstructural Evolution ◽  
Superplastic Deformation ◽  
Yield Function ◽  
Internal Variables ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Initial State ◽  
Plane Stress Condition ◽  
Deformation And Failure

Currently available models describing superplastic deformation are mostly based on uniaxial tensile test data and assume isotropic behavior, thus leading to limited predictive capabilities of material deformation and failure. In this work we present a multi-axial microstructure-based constitutive model that describes the anisotropic superplastic deformation within the continuum theory of viscoplasticity with internal variables. The model accounts for microstructural evolution and employs a generalized anisotropic dynamic yield function. The anisotropic yield function can describe the evolution of the initial state of anisotropy through the evolution of unit vectors defining the direction of anisotropy during deformation. The generalized model is then reduced to the plane stress condition to simulate sheet metal stretching in superplastic blow forming using pressurized gas. Different ratios of biaxial stretching were investigated, including the case simulating the uniaxial loading condition, where the model successfully captured the uniaxial experimental data. The model is also used to develop a new forming pressure profile that accounts for anisotropy and microstructural evolution.

scholarly journals Effect on the mechanical properties of sheet metals after the use of drawbeads in deep drawing

2018 ◽  
Vol 190 ◽  
pp. 05001 ◽  
Author(s):  
Harald Schmid ◽  
Marion Merklein
Keyword(s):  
Mechanical Properties ◽  
Sheet Metal ◽  
Deep Drawing ◽  
Optical Measurement ◽  
Detailed Knowledge ◽  
Complex Materials ◽  
Initial State ◽  
Blank Holder ◽  
Strip Drawing ◽  
Main Effects

The use of modern and more complex materials leads to a need for detailed knowledge and controlling of the material flow. Next to the blank holder force or the lubrication system, drawbeads are nowadays one common way to bring serial forming processes under control. Although drawbeads are already well investigated regarding their retention forces, the effect on the resulting mechanical properties after a drawbead passage is not analysed in detail yet. This work will show the influence of a common drawbead geometry used in forming processes on typical mechanical properties of sheet metal. Therefore, two different sheet metal materials are preloaded in a modified strip drawing test with industrial used drawbead geometry. In testing, three different pressure levels between 2.5 MPa and 7.5 MPa and three levels of drawing speed between 10 mm/s and 50 mm/s are combined to nine variations which will be examined. Afterwards, specimens are cut out by a laser cutting machine of the drawn strips. Those already preloaded and deformed specimens are then tested under standard conditions with the use of an optical measurement system. The results like tensile strength or elongation at fracture are compared to the initial state and each other and discussed with consideration of pressure and speed levels to work out the main effects. Those results are a contribution for the optimization of deep drawing simulations of parts including drawbeads or to evaluate the influence of drawbeads on forming processes to specify or even expand process limitations.

scholarly journals Vlasov simulations of trapping and loss of auroral electrons

2015 ◽  
Vol 33 (3) ◽  
pp. 279-293 ◽  
Author(s):  
H. Gunell ◽  
L. Andersson ◽  
J. De Keyser ◽  
I. Mann
Keyword(s):  
Double Layer ◽  
Electron Distribution ◽  
Electron Distribution Function ◽  
Distribution Functions ◽  
Initial State ◽  
Voltage Electron ◽  
Auroral Electrons ◽  
History Of ◽  
Auroral Current ◽  
Acceleration Voltage

Abstract. The plasma on an auroral field line is simulated using a Vlasov model. In the initial state, the acceleration region extends from one to three Earth radii in altitude with about half of the acceleration voltage concentrated in a stationary double layer at the bottom of this region. A population of electrons is trapped between the double layer and their magnetic mirror points at lower altitudes. A simulation study is carried out to examine the effects of fluctuations in the total accelerating voltage, which may be due to changes in the generator or the load of the auroral current circuit. The electron distribution function on the high potential side of the double layer changes significantly depending on whether the perturbation is toward higher or lower voltages, and therefore measurements of electron distribution functions provide information about the recent history of the voltage. Electron phase space holes are seen as a result of the induced fluctuations. Most of the voltage perturbation is assumed by the double layer. Hysteresis effects in the position of the double layer are observed when the voltage first is lowered and then brought back to its initial value.

Chances and Challenges in Joining by Forming with a Flat Counter Tool

2005 ◽  
Vol 6-8 ◽  
pp. 203-208 ◽  
Author(s):  
Reimund Neugebauer ◽  
R. Mauermann ◽  
Stephan Dietrich
Keyword(s):  
Sheet Metal ◽  
Metal Parts ◽  
Joining By Forming ◽  
Sheet Metal Parts ◽  
New Methods ◽  
Process Reliability ◽  
Conventional Technology ◽  
New Applications

Two new joining methods for sheet metal parts, dieless clinching and dieless rivet-clinching are introduced in this paper. With these methods all formable materials can be joined. Contrary to conventional technology in joining by forming these new methods are working with a flat anvil as a counter tool instead of a contoured die, which has a number of advantages. The process has become simpler, the process reliability is increased, misalignments of the joining tools don’t effect the quality of the connection anymore and even new applications, such as the joining of materials with a limited malleability become possible. Examples of realized connections and FE-calculations of the joining processes are presented.

scholarly journals Manufacturing history of etanercept (Enbrel®): Consistency of product quality through major process revisions

mAbs ◽  
2017 ◽  
Vol 10 (1) ◽  
pp. 159-165 ◽  
Author(s):  
Brian Hassett ◽  
Ena Singh ◽  
Ehab Mahgoub ◽  
Julie O'Brien ◽  
Steven M. Vicik ◽  
...  
Keyword(s):  
Product Quality ◽  
Major Process ◽  
History Of ◽  
Manufacturing History

Stability of the subsurface ocean of Pluto

2020 ◽  
Author(s):  
Jun Kimura ◽  
Shunichi Kamata
Keyword(s):  
Initial Conditions ◽  
Thermal Evolution ◽  
Heating Rates ◽  
Initial State ◽  
Radiogenic Heating ◽  
Subsurface Ocean ◽  
Order Of Magnitude ◽  
History Of ◽  
1D Model ◽  
Ice Shell

<p>We explore the long-term evolution of Pluto’s subsurface ocean in the absence of an insulating clathrate hydrate layer. Numerical simulations of the thermal history of the interior are performed using a 1D model assuming Pluto was initially differentiated into an outer hydrosphere (H<sub>2</sub>O shell) and an inner rocky core. We consider two endmember initial conditions: the hydrosphere was either entirely molten or frozen. We also consider different radiogenic heating rates, core sizes, ice reference viscosities, and ammonia concentrations. Our results indicate that the present-day Pluto can possess a subsurface ocean if the ice shell is purely conductive or only weakly convective. Our results also indicate that the initial state affects only little on the evolution scenario. These results strengthen previous conclusions obtained based on thermal evolution studies with limited calculation conditions. The thickness of the present-day ocean can be up to ~130 km, depending on the radiogenic heating rate and ice reference viscosity. The reference viscosity of ice required to maintain an ocean until today for the case of a CI chondritic core is approximately an order of magnitude higher than that for the case of an ordinary chondritic core. We also find that a thick subsurface ocean can be maintained until relatively recently for a dense small core case, which allows the formation of high-pressure ice at the seafloor. An inclusion of ammonia in the ocean increases the possibility of the current presence of a subsurface ocean even in the case of 1 wt% NH<sub>3</sub> at the initial.</p>

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