A Study Of The Forming System For Squeeze Casting

Squeeze casting (SC) recently commercialized has been attached more importance bymore countries in the world, due to its major advantanges such as improving componentmechanical properties, decreasing casting defects.This also makes the production competetionof squeeze casting more serious. Since equipment, moulds, process parameters and othersfactors affect the forming process of squeeze casting, research and development efforts in thestragetic areas of these support techniques and tools to reduce production lead-time and costand to enhance quality and productivity, are very much needed.Under the funding ofGuangdong&Education Ministry IAR project (Grant 2009A090100026), this thesis studiesthe forming system for squeeze casting constructed by the hardware and software related tosqueeze casting forming process from the view of system engineering.On the basis of the analyses about the recent studies and the forming process of squeezecasting, this thesis puts forword the forming system for squeeze casting, at the same timeillustrates the features of this system. Following this, the general functions and theinformation architecture of this forming system are discussed, and then a general structure forit is presented, which is composed of the mould design system, the process parameter designsystem and the core, squeeze casting equipment system.During designing the squeeze casting equipment, axomatic design (AD) theory isintroduced and the method for functional design of axiomatic design based on connections ispresented, in order to actively avoid functional coupling of axiomatic design. The basicprinciples and rules about this method are emphasized. After that, the AD framework forsqueeze casting equipments is constructed and the squeeze casting with the locking force of2500kN is designed based on this framework. The FEM analysis on the general structure ofsqueeze casting equipment designed is also conducted to verify and keep the design resultsmore rational. Then, the paper puts forward the method to evaluate the production permanceof squeeze casting equipment in the view of logistics. The relations of squeeze castingequipment and logistics is illustrated, and the evaluation system made of five indexes issuggested, which are idle loop time, production cycle time, metal feeding and locking time,utilization rate, the number of logistic entities handled. Meanwhile, the logistic simulation ofsqueeze casting equipment in Flexsim software is discussed; the simulation model, cases andresults are included.After summarizing the conventional design methods of squeeze casting process parameters, on the basis of the relations between material composition and processpropertiesof casts, simultaneously considering the application trends of knowledge management andcasting simulation, the paper proposes the new process parameter design method, whichincludes two steps: i) getting initial values of process parameters from process knowledgemanagement system ; ii) input these values into casting simulation software as boundaryconditions to optimize. The process knowledge structure and the algorithm for getting initialvalues of process parameters by material similarity are constructed. The SC processknowledge management system is developed.The operation process for the forming system of squeeze casting is analysed, where maintasks about each operation stage are discussed. At the same time, the thesis analyses clampingfaults which will happen during running in the forming system. The determinant model aboutclamping faults is built; the control algorithms are proposed to control two main clampingfaults and the control module is illustrated too.Finally, the forming experiments of a thin step component are conducted in the formingsystem for squeeze casting mainly composed of the manufactured 2500kN squeeze castingequipment based on the design above and the process knowledge management systemdeveloped. It indicates that the design of the squeeze casting equipment is rational and theproposed methods are feasible and effective.