Lebed V. Re-engineering of large (compound/sleeved) products in heavy engineering industry based on batch technological operations of assembling-disassembling

3. Subject of research - re-engineering process for large-size products in heavy mechanical engineering. The object of research is re-engineering of large-size compound products in heavy engineering industry, based on batch technological operations of assembling-disassembling, which extend the operational life and ensure efficient use of resources during technological conversions. Research methods - methodological foundation: system analysis and comprehensive study of functional area and design parameters of large-size compound rolls and process systems for manufacturing, operation and re-engineering of these products. Theoretical and application results - in theoretical part of the work, during investigation of large-size compound roll female parts strain-stress state, the finite-element method based on COSMOS WORK software is used, and during solving assembling process thermo-mechanical tasks, the АВАQUS complex of general purpose finite-element programs is used. The stress level in female parts of compound rolling mill roll is controlled and diagnosed during experimental and industrial research on the basis of non-destructive magnetoelastic method. At simulation of female parts destruction process, the experimental-computation method is used. The method of solid state geometrical simulation is realized at operations development as for dismantling of large-size compound rolls and their subsequent assembling. For heavy engineering the application results are based on recommendations regarding rationale for selection of re-engineering processes for large-size rolling mill rolls and their following treatment at final parts manufacturing stage. The procedure and flow chart for composite surfaces forming cinematics software have been developed. According to evaluation results of resource-saving indices for the range of parts standard sizes, the minimal weight of large-size products has been set for 20 t, in this connection, during large-size compound rolls re-engineering process, there has been achieved the reduction of the parameters: materials consumption; factory labor hours; prime cost; energy consumption. The novelty is represented in development of theoretical, methodological and regulatory-methodical basis for product re-engineering based on batch technological operations of assembling-disassembling: - for the first time, the mathematical model has been developed to determine parameters of compound parts mating surfaces depending on residual stress; - the further development was received by designing methodology for batch technological operations of assembling-disassembling; - for the first time, the fretting wear and fatigue mathematical model has been developed and tested to determine their parameters at product designing stage taking into account the design of rolling mill roll and coating application scheme for male part mounting surface, that enables to predict fretting processes parameters; - there has been improved the mathematical model for determination of technological parameters for large-size compound product assembling by means of thermal action; - there has been developed a method for research of part stress-strain state parameters during assembling of large-size compound rolling mill rolls by means of thermal action; there has been developed adaptive control algorithm for assembling process. Implementation - the results of this work were implemented in "NKMZ" PAT (PJSC) (Kramatorsk). The reconditioned compound rolls are used in rolling mill stands of Ukrainian and Russian. Field of application - heavy mechanical engineering.