Calculation of parameters of profiling technology with longitudinal tension of thin-walled parts of heat exchangers

Abstract

Plate heat exchangers are produced at specialized enterprises using powerful press equipment and special stamping equipment. Heat exchangers are heat transfer elements that transfer heat between two media. The shape and dimensions of the heat exchangers are selected based on the physical properties of the coolants and their movement. Traditional technologies for profiling heat transfer elements by stamping are energy-intensive and, in some cases, cannot ensure the quality of heat exchangers made of high-strength alloy steels, aluminum, and copper alloys. In modern conditions, it may be rational to produce heat-transfer thin-walled profile elements based on the technology of profiling by local force with longitudinal tension, which allows the production of a variety of thin-walled profiles with the necessary accuracy and dimensional stability. This study aims to develop an engineering methodology for calculating force parameters for adjusting profiling equipment and determining the geometric parameters of technological equipment. It is possible to obtain the necessary dependencies when solving the rigid-plastic bending problem of a staff under the action of a longitudinal tensile load. In the theoretical analysis of the process of staff deformation, hypotheses and assumptions were used that are used in the study of rigid-plastic bending and are based on the deformation theory of plasticity. The hypothesis of the plane sections is used. This problem was considered for an ideal rigid-plastic material with linear reinforcement. The results obtained: the stress-strain state of a staff made of a material with linear reinforcement during its rigid-plastic bending with longitudinal elastic tension was analyzed. The position of the neutral stress layer in the cross-section was determined. Dependencies were obtained to determine the relative bending moment required for bending the staff with longitudinal tension. Analytical dependencies that allow determining elastic springback and residual curvaturewere obtained. Software was developed for practical calculations of geometric parameters of technological equipment and power parameters of profiling equipment.