Resumen

MORALES, R. A  y  CANDAL, M. V. Diseño y fabricación de un molde de termoformado utilizando herramientas CAD/CAEDESIGN AND MANUFACTURING OF THERMOFORMING MOLD BY USE OF CAD/CAE TOOLS. Rev. Fac. Ing. UCV [online]. 2006, vol.21, n.1, pp.83-99. ISSN 0798-4065.

The main purpose of this study was to evaluate a thermoforming drinking glasses mold for detecting flaws that can be happening during the manufacturing operation and for considering recommendations to correct it, in such way of obtaining pieces with required dimensions and appearance. With this work, it is looked for to establish the importance of the use of CAD/CAE computational tools for the thermoforming process evaluation in such way of validating the experimental results obtained in machine during the manufacturing process of the pieces. To achieve this, the disposable drinking glasses were made in a Brown S-1150 Thermoforming with the purpose of observing the default and good pieces. Subsequently, the mold was validated using CAD software. For that, three-dimensional representations of the glasses and the mold were made using solid modeler software and they settled down, based on experimental races with a polymeric resin (High Impact Polystyrene HIPS). Twelve conditions related with the variation of the vacuum pressure and cycle time were made. When comparing the data obtained in the simulation with the experimental ones similar tendencies were observed with variations of 30,59% for the walls and 137,75% for the bottom of the glasses, attributable to the plugs waste and to the approaches used about the process. The principal conclusion is based on the sheet temperature, defined by the cycle time, because is the prosecution parameter that more influence has on the pieces final thickness distribution. In addition, in the male or positive molds, the area corresponding to the pieces bottom will always present bigger thickness. Moreover, with the thermoforming simulation, flaws can be identified in the piece model in order to correct them during the design of the mold and the pieces manufacturing process.

Palabras clave : thermoforming; computer assisted engineering; computer assisted design; plastics pieces; validation.