Kartamyshev D. Improvement of the forging forming processes with hollow parts based on the methods of sequential combined extrusion

Object of research – precision forging extrusion process. The aim of the work is to increase the efficiency in processes of precise volume stamping with hollow parts based on the use of methods in sequential combined extrusion and development of recommendations for designing stamping processes that reduce the complexity and energy consumption of the technological process. Methods of research – energy method of the upper assessment (the balance of power), the finite element method, the methods of physical modeling and strain gauging to measure technological forces, the method of dividing grids and hardness measurement for determining the stress-strain state of workpieces. Theoretical and practical results – based on the established laws of force, deformation modes calculated dependences for force parameters, and methods of designing for technological processes in consecutive forward with distribution and cross-forward extrusion of hollow parts, possibilities of new ways for receiving hollow parts with a difficult external profile are investigated. Defects such as dimple based on sequential control of the tool kinematics for combined extrusion. Novelty - on the basis of theoretical methods for the first time the models which have allowed to increase accuracy of forecasting for efforts of parts forming are developed, analytical dependences for calculation of modes in cross-longitudinal extrusion are specified for the first time; for the first time the peculiarities of the stress state in the workpiece were evaluated, deformation paths were constructed and dangerous rigid zones in the deformation center were identified on the basis of simulation results; the possibility of combining sequential and combined extrusion schemes in one process is established, which provides expansion of the parts nomenclature. Implementation - new technological recommendations for combined extrusion are transferred and developed designs of dies using detachable matrices, tested and accepted for implementation in production. Scope – metal forming, precision forging.