RESEARCH OF THE STRESS-STRAIN STATE OF THE MAIN CYLINDER OF THE HYDRAULIC PRESS

Abstract

In the article the stress-strain state of the main cylinder of the hydraulic press for the manufacturing of large-sized plastic products has been investigated using software of finite-element analysis. It is established that the stress-strain state is characterized by a general and local uneven distribution of stresses and displacements. The nature of the distribution of stresses, deformations, displacements, safety factors along the length of the cylinder allowed conditionally divide the cylinder into three characteristic zones: flange zone, Lame zone, bottom zone. In each of the zones we found the areas in which the maximum stresses and strains are observed. It was found that the maximum equivalent stresses calculated according to the Huber-Mises energy theory of strength are observed on the inner surface of the cylinder, and in their fillets in the zones of the bottom and flange. A comparative analysis of the stresses and displacements determined by the Lame formulas and the finite element method showed that in the Lame zone their values do not change significantly. Studies on the influence of the radius, which varied over a wide range, and the fillet angle, made it possible to establish the region of maximum principal and equivalent stresses and reduce their magnitude. The calculations revealed the fillet region in which the axial tensile stresses act and determine the fillet angle at which the axial stresses are equal in magnitude and sign The study allowed to change the geometry of the cylinder, reduce the stress in the cylinder fillet and its weight. The results of the study can be applied to improve the existing and design of new hydraulic presses of the chemical industry, as well as the basis for further research.