Method for calculating the forces required when bending pipes of small cross-section with a rectangular profile

Curved pipes of small cross-section rectangular profile (3,6x1,8 – 11x5,5 mm) are widely used in antenna-feeder devices of spacecraft. They are required to ensure dimensional accuracy, in the bending zone no more than ±0,05 mm, for this a choice of methods of technological modes is necessary. The object of the study is a small-section pipe billet made of copper M4, which must be bent to obtain a bending angle of 90°. The purpose of the study is to develop calculation methods necessary for the implementation of the technological process of bending small-section pipes, with justification of bending efforts. The paper analyzes the methods of bending rectangular pipes. The most rational method was chosen, bending using a rigid mandrel. Based on the selected bending method, a calculation model was compiled. The methodology and calculation algorithm have been developed and the analysis of the calculation results has been carried out. As a result of theoretical studies, with the help of calculations, the degree relationship of the effort of bending from the bending radius was revealed, the bending forces from the bending radius – the larger the bending radius, the less effort is required for bending. The calculation can be used to determine the size of the bending equipment and the bending force of the pipe of small cross-section, allows you to choose the most optimal mode of the technological process.