| The heater radiation chamber collector is employed to disperse low hydrocarbon and collect aromatic petrochemicals in integrated purification and chemical reformers.so as to unravel this drawback,this subject takes the hot temperature characteristics of the fabric and also the thermoplastic deformation mechanism because the place to begin,obtains the fabric parameters and connected theories needed for the finite part analysis,and so uses the finite part software system to research very well the temperature and stress fields fashioned throughout the recent drawing method of the collector tube stubs.Firstly,warm temperature tensile experiments were administrated at a temperature of800-900℃and a strain rate of 0.01-1s-1mistreatment associate degree electronic universal testing machine,followed by metallographic observation of the experiments.the fabric characteristics of 1.25Cr0.5Mo steel were obtained:（1）thermoplastic properties at completely different temperatures;（2）at a precise temperature,the warm temperature physical science stress will increase with the acceleration of the strain rate,and therefore the quicker the speed of the tensile take a look at,the larger the grain refinement,i.e.,the larger the height stress within the warm temperature tensile curve;at a precise strain rate,the temperature at 850℃the utmost peak stress is obtained,and therefore the analysis of metallographic organization shows that the grain refinement is deeper at 850℃,and therefore the grain boundary space is giant and twisty,that isn’t contributing to crack enlargement by identical external load,thus it shows an oversized peak stress;（3）The warm temperature physical science stress hyperbolic intrinsic model of 1.25Cr0.5Mo steel springs,and therefore the accuracy of this intrinsic model is verified.Secondly,by learning the idea of thermoplastic deformation of steel,the mechanism of metal thermoplastic deformation and also the mathematical model of temperature and stress fields shaped by the thermoplastic deformation method area unit derived.The thermoplastic deformation mechanism includes intra-granular deformation and grain boundary deformation,that explains the method of thermoplastic forming of metals from a microscopic purpose of read.The mathematical models associated with the temperature and stress fields of metal thermoplastic forming square measure analyzed,and therefore the resolution conditions square measure provided for the finite part simulation and analysis.Finally,ABAQUS finite component simulation was wont to simulate the temperature and stress fields of the heater radiation chamber assembly tube stub of tubeφ1524×46material 1.25Cr0.5Mo below totally different influencing factors of heating space,heating temperature,friction constant and drawing speed.supported the info associated with the temperature and stress fields of the assembly tube below totally different process factors obtained from the simulation experiments,the causes of hot-drawing forming of the assembly tube stub were analyzed,and a collection of method parameters with a heating temperature of 850℃a most diameter of 217mm within the heating space,a friction constant of 0.5,and a drawing speed of 60mm/s was projected,The residual temperature and stress fields generated by this method parameter area unit little in value,little residual stresses generated by temperature and also the little residual stress field s generated by the structure cause a reduced degree of irregular deformation of the collector tube.In this project,the temperature and stress fields fashioned by the new drawing of the collector tube stubs are studied by the finite part methodology,that not solely explains the causes of thermoplastic deformation made by the new drawing of the collector tube stubs,however conjointly comes up with a group of method parameters which will scale back the irregular deformation and improve the responsibility of the collector tube producing. |
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