EL.V.AL. S.A. is the major aluminum production and processing company of the VIOHALCO Group, the largest metals group in Greece. The new industrial roller to be installed at EL.V.AL. was designed by TEKA Systems S.A. a company offering engineering services for the industry. A roller in an aluminum processing company is a very important piece of machinery that needs to operate safely and efficiently. This can be achieved only if the large assembly of the roller parts works elastically, otherwise the large piston forces of 150 to 200 tn required for the thickness reduction of the aluminum slabs will cause undesirable or even disastrous results.
TEKA Systems ordered to SIMTEC a FEA model for the roller, which was constructed in ANSYS Mechanical for the simulation of its static structural behavior in standard (150 tn) or overload (200 tn) operating conditions. Initially, the roller assembly of 3123 parts, was imported from AUTODESK Inventor into ANSYS DesignModeler. Fig. 1 shows the assembly as viewed in AUTODESK Inventor, whereas Fig. 2 presents the symmetric model in ANSYS DesignModeler after the import and the optimization process. Next the FEA mesh was constructed as shown in Fig. 3. The final step was to provide the loads of the symmetric model, i.e. the rolling piston force, the self-weight and the moments arising from omitting the gear box that drive the roller’s two vertical shafts from the FEA model.
The resulting strain and stress field for both 150 and 200 tn piston force, showed that inelastic deformation was detected only in very small and confined regions near corners. This is very typical in FEA of “false” high stress values, which does not reflect to reality. In most of these few regions bends or chamfers were substituted by sharp-cornered equivalents during geometry simplification, therefore their stress-relief effect was not represented in the FEA model. Concluding, the FEA model showed that the roller will perform elastically for loads up to 200 tn. Fig. 4 shows the Equivalent Stress in MPa of the vertical roller for the overload case of 200 tn and Fig. 5 the total deformation in mm of the machine for the standard case of 150 tn.