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The purpose of the paper is to highlight the advantages that the automotive industry gains by using hydroforming and hydroperforation processes in automobile manufacturing. In recent years, progress has been made concerning the equipment and tools needed to carry out the hydroforming and hydroperforation processes. As these machines and tools have been perfected and produced on a large scale, becoming cheaper and more cost-effective were main scopes of the development, increasing the mass production, supporting the automotive industry, as well, is another goal. The improvement of the tools used and the equipment determined that these processes have to be extended for a quite large number of components of the vehicle, in the production of large series. A comparative analysis and advantages of the technology are presented regarding the impact on the environment of these processing, hydroforming, and hydroperforation processes, in relation to other traditional processing processes

When perforation by cold plastic deformation processes of long round pipes, the technological problems appear primarily at the deformation of the part section, in the perforation area by losing the stability of the part, in the case of holes made at a distance from the pipe ends. The purpose of the research was to determine the influence of the constructive shape of the pipe clamping devices in the perforation area, in order to determine the device that offers the best stability of the section, to allow obtaining possible holes as large in diameter. The research was based on the application of materials strength methods and the Castigliano method of solving the indeterminacy, related to the process of cold plastic deformation. The research materialized by determining some calculation relations and specific diagrams regarding the diameter’s variation of the perforated holes in the air environment, depending on the dimensions of the part and the mechanical characteristics of the part material, for different forms of clamping devices. The calculations were performed considering that the perforation is performed in air, with a punch applied from the outside of the considered piece. The calculation relations and the obtained diagrams allow the determination of the maximum orifices, for certain dimensions of the pipes and for different mechanical characteristics of the part material. At the conclusions, a comparison was made of the results obtained for the variants of clamping considered devices and the optimal shape of the device was established, which allows the making of the largest perforated holes in the part.

This paper addresses a topical issue around the world, i.e. the issue of minimizing environmental and human pollution. The subsequent aim of this paper is to develop an appropriate methodology for assessing the negative impact potentially exerted by a manufacturing process on the environment and workers. Research has been conducted in order to determine an index of negative impact on the environment and workers. Through the research carried out, the determining factors in environmental pollution have been identified and quantifiable indicators have subsequently been associated with them. Additionally, an impact index has finally been determined by calculation. This methodology was applied in the case of the drilling/perforation processes on long tubular parts, particularly featured in the automotive industry. The emerging results show the negative impact exerted by each of the processes considered on the environment. The manufacturing processes in which the impact index has low values close to zero are significantly close to a standard of non-polluting manufacturing processes with zero-impact index. The methodology adopted in this paper has led to the identification of the range of pollutants that should be improved, removed or at least reduced, in order to achieve a zero-impact index.

The purpose of this paper is to highlight the influence of the dimensional characteristics and mechanical strength characteristics of the pipe material on the diameter of the perforated holes in these long pipes, to maintain the stability of the pipe shape in the perforated area. The research aimed to establish the maximum limit dimensions of holes that can be made in long round pipes with thin walls, through perforating by cold plastic deformation in air, using only a punch applied to on the outside of the pipe, for a particular case of pipe clamping. Following the research, the mathematical relations between the maximum diameters of the holes that can be obtained in round pipes, in correlation with the dimensional characteristics and the mechanical resistance of the material, are presented. The characteristics taken into account are the outer diameter of the pipes, the thickness of the pipe wall, and the permissible resistance to rupture of the part material. In the conclusions, it is specified that the determined mathematical relations allow the construction of variation diagrams and the determination of the maximum possible diameters, for other dimensional characteristics of pipes and for other mechanical strength characteristics of different materials.