Ischenko O. Substantiation of project and technological parameters of shearing dies by improving of basic elements strength and rigidity

Object of research – shearing dies for the cold sheet-metal stamping. Purpose of the work – improvement of operational properties and substantiation the design and technological parameters of dies tooling elements for the cold sheet-metal stamping based on the analysis of their stress-strain state and taking into account the contact interaction. Research Methods - methods of metalworking theory, elasticity theory, variational inequality theory, finite element method, computational and experimental method for determining the loading laws of die tooling elements based on the use of pressure-sensitive films, theory of three dimensional geometric parametric solid state and surface modeling. Theoretical and practical results – the main parameters in the stamps design with the required accuracy and strength during the technological operations in the manufacture of special purpose vehicle’s details are substantiated. The developed specialized program-model complex provides the designer with the ability to implement a refined analysis of the stress-strain state of dies tooling elements at the final design stages. Novelty – the characteristic features of the stress-strain state of dies tooling elements with the multiple contact interaction between elements are defined due to theoretical development. Refined dependencies for components of stress-strain state of the shearing dies elements on the design and technological parameters were established. It became possible to quasistatize the problem of determining the stress-strain state of dies tooling elements. For the first time it was established that а complex stress state with sharp stress gradients was realized under fixing a guide pin and a hollow bar in the base plates of re-adjustable dies. The fixation was made by means of polymer compounds in thin interlayer’s, which were formed by the action of operating loads. Implementation – developed software and model complexes which were used for forming the recommendations served as aground for designing dies embedded by some of the plants. Scope – metal forming, precise sheet-metal stamping.