Structural Design And Analysis Of Welding Manipulator For Cross Pipeline With Different Diameters

With the vigorous development of manufacturing industry,the aging of China's population and the continuous innovation of the labor system,more and more industrial manipulators are applied in production practice.Welding technology plays an important role in mechanical processing,so welding manipulator is also an important part of industrial manipulator.In recent years,the automation level of manufacturing industry has been continuously upgraded,and the automation requirements have been constantly improved.The requirements for flexibility,positioning accuracy and motion performance of welding manipulators have also been put forward higher and higher.In this paper,a rigid-flexible coupling welding manipulator for cross-pipe with different diameters were designed according to the project requirements of the company.Firstly,the structural characteristics,dimensions and welding requirements of the workpiece to be welded were analyzed.Because of the complex welding of pipeline system,higher requirements were put forward for welding sealability and motion flexibility of the manipulator.Then a rigid-flexible coupling motion scheme were proposed to meet the actual production needs.Secondly,the structure of the rigid-flexible coupling welding manipulator were designed,the degree of freedom of motion and the working range were analyzed,and the overall payload and repetitive positioning accuracy of the manipulator were determined by combining the flexible joint of the working end.According to the structural parameters,the mechanical structure design were carried out.The modular design concept were adopted to design the welding manipulator.According to the motion performance,the whole module of the manipulator were divided into three parts: base transmission module,joint sliding module and wrist rotation module.The driving joint,transmission structure and flexible joint hydraulic bag were designed respectively,and the key rod group and the overall structure were completed.The rigid manipulator base adopts 4-DOF configuration of RPPR connection form,and improves the positioning accuracy by compensating the trajectory error of flexible joints.The scheme of rigid-flexible coupling welding manipulator were determined.The rigid base of the rigid-flexible coupling welding manipulator designed in this paper weresolved by kinematics,the model of the flexible joint were completed,the position and range of motion were analyzed,and the envelope of the rigid-flexible coupling motion is determined.Finally,ANSYS were used to check the strength of key parts,static analysis and fatigue analysis of the bearing arm were carried out,and the reliability of the whole arm were verified.The working state of the rigid-flexible coupling welding manipulator were analyzed,and the key parts which were easy to be damaged were determined.Static analysis,fatigue analysis and reliability analysis were carried out respectively to calculate the service life of the welding manipulator.Through the content of this paper,the structure design,motion performance,mechanical analysis and key parts checking of the rigid-flexible coupling welding manipulator were carried out,and the requirements of hardware design for the welding of the closed pipeline system are realized.Figure [50] Table [6] Reference [73]...