TPT May 2011

A rticle

Advanced new approach by SMS Meer It was first clear that an important goal should be to create a FEM computation model as realistic as possible, as demanded from every FEM computation. For this reason more information was to be processed than to date in order to further improve the previous results. Not that the results of the previous computations could not be used – quite the opposite: In order to get to this point, a great deal of development work first had to be invested in the new computations. But if this new route was to be taken, the results at the end should preferably surpass the old results. SMS Meer is in constant contact with plant owners and checks the results of the computations. Measurements on current products and comparisons with the simulation data had already proved that the computation closely images the reality. Due to the interaction of the various plant components on the endless strip, a relatively long computation element (18m) was selected in addition to the boundary conditions. Kinematics In a computation, the rolls should behave exactly as they do in reality. The rolls were therefore defined as rotating bodies. The rotational axes are defined directly in the simulation software. With the surfaces of the rolls, the friction is also taken into consideration with the Coulomb friction model. Drag and drop An important initial, however, was not the computation proper, because the future computation was to be carried out essentially with MSC software as before. After all, in the past valuable information was often gained from the computations. In this step a method was developed in which the contact geometries – ie the contact geometry of all the rolls, including the strip – could be transferred directly to the simulation environment in both dimension and position. It is therefore now possible to implement a flexible and unrestricted change in the machine properties. It is now no longer necessary to input the complete positioning and the roll geometries as these are already available in the CAD system. No matter how complex the position of the forming elements may be, a single mouse click is sufficient to position them precisely. Complex or even exotic plant components now require no additional modules. Laborious manual input of coordinate values in tables is also no longer necessary. Transfer errors are thus also reliably ruled out.

Roller-beam

Flexibility in the design For a manufacturer of plants and machines it is important to be able to try out completely new and unprecedented ideas. The possibilities of a 3D system are unlimited, and just as unlimited are now also the possibilities for testing these systems. Material A realistic simulation is only expedient with data from practical applications. Particularly when not only a qualitative, but also a quantitative analysis is required, it is crucial to use the right flow curve. The plastic deformation is computed with the plasticity model of a cold forming process using Ludwig’s equation: A further goal should therefore be to use flow curves previously obtained for the materials actually used as the basis for the forming process. Here SMS Meer can call not only on a huge collection of data, but also on long-standing contacts to institutes in this field. In some cases the material samples are sent directly by the customers to SMS Meer. Conclusion With this new concept the computations of SMS Meer come considerably closer to reality than using common computations available on the market. This encourages us to continue along this path and confirms that our approaches are correct. Today the simulation computation at SMS Meer even integrated into the 3D design work is not only easy and logical to use, but also completely freely configurable thanks to its structure. Three elements are successfully combined: 3D-CAD, FEM and the real process.

Sample material for realistic flow curves

SMS Meer GmbH – Germany Fax: +49 2161 3501862 Email: sven.renkel@sms-meer.com Website: www.sms-meer.com

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