A user-friendly computational algorithm for the structural analysis of wrapping machine rotating rings

Abstract

Wrapping machines usually consist of a two-or a four-column frame, supporting a huge rotating ring, connected to a prestretch unit with film coil carrier. Stiffness is a key point of packaging machines, since it is strictly related to the accuracy of the wrapping task. It depends on the stiffness of the frame, which can be achieved by the four-column architecture, and on the ring constraint system. As a consequence, the ring structures are usually highly statically indeterminate. Nowadays, there is an increasing demand for higher rotational speeds and more reduced operation times. Therefore, an accurate structural analysis of the ring, considering its actual loading and constraints is more and more important. The structural analysis of the rotating ring is treated by many references; however, such a statically indeterminate constraining makes this problem highly complicated. The goal of this paper consists in the development of a general and original computational algorithm for the structural analysis of rotating rings. The results are collected in a user-friendly way in terms of normalized internal loads, so that they can be of a great help even for not expert users. This model has been experimentally validated and easily applied to case studies and optimization tasks.

A Methodology for the Lightweight Design of Modern Transfer Machine Tools

“…Since a correct estimate of the stiffness of a complex assembly is often related to an accurate modeling of its mechanical joints [16][17][18], the contact conditions between the support and the rotating table have been modified in order to achieve a more accurate FE model. Hence, the bonded contact between the rotary table and the support has been replaced by a set of four M12 12.9 class screws ( Figure 11): this bolt pattern replicates that being actually used on the Transfer Machine with nine divisions.…”