Study On Load Transfer And Monitor Of Huge Precision Die Forging Hydrostatic Press

300MN Die Forging Hydrostatic Press and 100MN multi-direction Die Forging Hydrostatic Press are the main equipments of national defense and basic industry. They have played a very important role in the manufacturing of military and civil productions. As a matter of fact, both of them were designed and made in the seventies of last century. With the rapid development of modern technology of national defense and energy industry, their production abilities and precision can not meet the requirement of modern technology. Therefore, some departments concerned, such as Commission of Science Technology and Industry for National Defense, State Planning Commission, Chinese nonferrous metal limited company, have set series new projects respectively so as to upgrade the function and reform the technology of Hydraulic Forging Press.In the extremely huge mechanical structure of the huge Die Forging Hydrostatic Press, load transfer and the control of 3D-spatial deformation are the core issues of its design, and they are also the foundation of accurate manipulation and operation control. In this paper, we take the 300mn Die Forging Hydrostatic Press as subject investigation, combine with the mechanics and structure of mega-frame, backing plate frame and conjunction technique, then built a mixed finite element method of multi-body elastic contact problem. In addition, Strength Theory, Determination Technology and Computer Technology were used in the study. As a result, we found the laws of the load transfer and deformation of the Press, such as the characteristics of load evolvement of statically indeterminate structure, generative mechanism and reason of the appended load, and several influential factors of local stress deformation. Base on these theories, Working Condition Monitoring System of the Press and Protecting System were developed. All of this have provide theory basis and technology guidance for the Press's technology innovate and function upgrade.The main studies are as follows:1,The method of finite element of 3D elastic contacting problem of large-scale structure:Combining with structural and mechanical characters of large frame structure, backing plate and screw contacting subassembly, we have set up calculating method and software of multi-body nonlinear contacting problem, nonlinear contacting characteristic frame strength and stiffness analysis. And these were under multi-dimensions multivariate statically indeterminate and strong stress. This thesis have solved the strong and deformation analysis problems of multilayer backing plates subassembly, screw contacting subassembly, which have offered new methods and paths for large-scale designing analysis.2,Strength and stiffness analysis of Hydrostatic Press backing plate group:Base on 300mn Die Forging Hydrostatic Press's characteristics, this thesis have set up the finite element model of 3D nonlinear elastic contacting analysis, developed a kind of mixed solving algorithm of finite element, and got backing plate group contact layers contact stress' distribution and parameter rules, found out load distributing, forging piece shape and supporting components frame mode relevant machine-made.3. Strength and deformation analysis about upright column and screw assembled parts:A double nonlinear finite element method about elastic-plastic contact problem is brought up, in order to solve the screwed connection heavy load problem. This thesis built the contact mechanical model of upright column and screw assembled parts. In addition, stress distribution regulation of the upright column under variable load condition was found out. There are also some other regulations, such as joining strength of upright column screw, the possibility of pressurization and so on.4. Finite element method analysis and evaluation of framework stiffness:This thesis also built finite element method analysis model of hydrostatic press's main framework (up beam-upright column-fixed beam-down beam). And found out true stress,dynamic stress peak and stress distribution of 300MN Die Forging Hydrostatic Press under variable load condition. In addition, stress station and 3D deformation regulation of the main framework which under different load condition were analyzed respectively. It lays great base on framework of the huge hydrostatic press's design and re-modification. A new way for the accuracy promotion was pointed out as well.5. Mechanical behavior analysis and strength evaluation of the main working cylinder:After many simulation and finite element calculation, overcome the effects of actual measurement positioning errors, This thesis have got plenty of information about the stress-strain state of the working cylinder. In addition, the cylinder's structure parameter was optimized design. These studies really means a lot to the intensity analysis of the working cylinder, so as to its life prediction and design.6,Stress online detecting of upright column and research of protection system:According to the analysis of stress and distortion of the upright column in Hydrostatic Press, we have developed the integrated working conditions detecting system and non-contact upright column stress protecting system for the 300MN Hydrostatic Press. It can fully meet the high-precision and real-time demands . Using the dynamic acquisition technology, the system can eliminate the errors of stress's detecting precision which were caused by the environment temperature, zero shift and other factors. This technology supplied a gap of high-precision detecting of upright column on the large-scale die forging hydrostatic press.Based on the results all above, This thesis put forward a feasible technical way for functions upgrading of 300MN Hydrostatic Press: Maintaining the main body structure , keeping the core components the same, and then by controlling the motion and load of the hydrostatic press, we can carry out the high synchronization of motion and restrain from deflect loads, and decrease appended loads. At the mean time, we can also decrease the distortion resistance and improve the equality of work-piece by optimizing forging technology. Thereby, the Hydrostatic Press's latent overloading can be translated into practical forging load ability on the main forging process. This technology has been carried out successfully, made the modernization rebuilding and function upgrading of the 300MN Hydrostatic Press a reality.