| With the continuous advancement of science and technology,robot technology is also developing rapidly,and the demand for industrial applications for robots is increasing.In the field of industrial welding,the harsh environment caused by noise,light radiation and smoke pollution makes fewer and fewer people engaged in welding work,which in turn leads to an increase in welding labor costs.This is undoubtedly increasing the processing cost for the small and medium-sized enterprises with low product quantity and professional welding workers,which leads to the reduction of production efficiency and enterprise efficiency.Therefore,in order to improve the welding productivity of small and medium-sized enterprises and make up for the shortage of welding personnel,a set of welding fixtures suitable for the frame chassis is designed by self-built welding robot workstation,and the welding method of CO2 gas shielded welding is adopted,the robot welding process research on the frame chassis of Q235-A steel.The main research contents of the thesis include:(1)According to the functional requirements of the arc welding robot,the robot welding workstation is built independently.Mainly consists of the robot body,electrical control cabinet,teach pendant,welding power supply,wire feeder,welding torch,ground rail,positioner and fixtures.(2)Independently design the fixtures suitable for the chassis of the frame and complete its assembly.Based on the "six-point positioning principle",the tooling fixture design is carried out for the frame parts of the frame and the structure of the whole vehicle.Utilizing the powerful 3D solid modeling function of UG software,the model of the frame chassis is restored according to the CAD 2D drawing size,and the structural rationality is analyzed,and the fixture design and assembly are completed.The pneumatic clamping device is adopted,and the on/off of the solenoid valve is controlled by Siemens PLC to control the lifting and lowering of the cylinder to realize the clamping of the components,so that the welded components are stably maintained on the positioning component.(3)Analyze the influence of the robot welding process on the weld quality and carry out the welding simulation experiment.In order to determine the position of the robot on the ground rail,the working range of the welding torch is determined in the actual working environment;in order to improve the quality of the weld,the internal parameters of the welding machine are debugged;In order to study the influence of various process parameters on the weld quality during the welding process,the advantages and disadvantages of various process parameters on the welding quality were analyzed;In order to save the adjustment time of welding parameters in actual working conditions,the simulation simulation is carried out by using Simufact.Welding virtual simulation software to guide the robot welding work.(4)The robot welding process parameter experiment was carried out and the mechanical properties of the weld were verified by tensile test and bending test.In order to study the influence of process parameters such as welding current,welding voltage,welding speed,working angle of welding torch and welding amplitude on weld formation,the test of flat weld and T-weld was carried out respectively.In order to verify the mechanical properties of the weld,in the well-formed weld results,the quality of the weld results obtained under the welding process parameters was verified by mechanical tensile test and bending test. |
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