Research On Lifting Mechanism Of Stud Tensioner Based On Stewart Platform

Multi stud tension machine is one of the main equipment in the nuclear power plant,which is responsible for the reactor pressure vessel opening and sealing.The efficient,accurate,remote automatic control multi stud tension machine have been the research hotspot of the nuclear power equipment at home and abroad.The lifting mechanism is an important part of the integral bolt tensioning machine,this structure bears a high gravity load,large up and down travel,in the lifting process requires strict control of the horizontal and horizontal displacement of the bolt stretching machine,its positioning accuracy directly affects the follow-up operation efficiency.The lifting mechanism of the existing bolt stretching machine in the actual operation process due to the operation accuracy is not enough to affect the operating efficiency,and sometimes it also need people enter the radiation environment for auxiliary operations.Presenting a bolt stretching machine lifting mechanism of series and parallel machine based on Stewart platform.Through the detail analysis of the structure and lifting process control of the lifting mechanism of the existing bolt stretching machine,which pointed out the shortcomings of the existing mechanism,combined with the characteristics of parallel institutions.A new type of multi stud tension machine lifting mechanism is proposed,which connecs the Stewart platform and the 3-RPS platform.The bearing capacity of the mechanism is high,the positioning accuracy is high,the structure is compact and the stability is good,which can simultaneously achieve the level adjustment,horizontal centering and lift operations in the process of the bolt stretching machine lift.Structural design and optimization of Stewart platform.Combined with the structural characteristics of the bolt stretching machine and the scope of the work of the platform structure of a reasonable layout.Based on the kinematic analysis,the structural parameters of the platform are optimized.The design results were validated by ADAMS mechanics simulation analysis software,ANSYS finite element analysis software was used to analyze the strength stiffness of the platform structure,and its key components has been selected model.Structure design of 3-RPS platform.Combined with the actual working conditions requirements of the bolt stretching machine,the structure and distribution of the 3-RPS platform are determined.Two kinds of control methods are analyzed by ADAMS mechanism dynamics simulation software,after comparison,to determine the platform control mode,ANSYS finite element analysis software was used to analyze the strength stiffness of the platform structure,and its key components has been selected model and verificated.Foundation of Stewart platform model prototype.Based on the above theoretical analysis results,the Stewart platform and other proportional reduction model prototype are designed,a platform control system is build based on Siemens SIMOTION motion controller control system,the motion control of the model prototype is realized.