Structure And Characteristic Analysis Of Welding Line Grinding Robot For Inner Wall In Pipeline

Metal welded joint pipes are widely used in the transportation of oil and natural gas.With the planning of oil and natural gas pipeline construction during the 13 th Five-Year Plan period,the demand for metal welded joint pipes will increase by nearly 10,000 kilometers per year;in order to improve the transportation of pipelines Efficiency and service life require grinding of the convex welding of the inner wall of the pipe;at present,the grinding of the inner wall of the small pipe diameter is mostly carried out by a hobbing cutter for inner wall cutting,and the disadvantage is that the entire inner wall is thinned and lowered.The inner wall of the pipeline with large service life and large diameter is artificially ground,which has low grinding efficiency,poor precision and affects the physical and mental health of workers.Foreign related equipment is restricted by import and the price is high and the cost performance is low.At present,domestic universities and research institutes research The inner wall grinding robot can only perform segmental operation in a certain pipe diameter;in view of this,this paper designs a new type of pipe inner wall weld grinding robot,which can be linear,circular or spiral.Continuous and staged variable diameter grinding in the welded steel pipe.In this paper,the theoretical analysis of the working principle of the whole machine is carried out.Based on the variable diameter and working requirements of the robot in the tube,the modular design method is used to design the walking part,the grinding part and the centering part respectively.The SOLIDWORKS is completed.The establishment of the three-dimensional model of the pipeline robot;the design of the dimensions of each mechanism;the selection of each motor was completed by relevant calculations.The dynamic characteristics of the pipeline robot are analyzed.It is analyzed whether the grinding trajectory of the grinding wheel meets the grinding requirements and the speed relationship between the whole machine and the rotating disc when the requirements are met.The size and obstacle of the roller under a certain traction force are analyzed.The relationship between the height and the height of the driven roller and the driven roller are different;the size relationship of each mechanism that meets the variable diameter function is analyzed;Finally,according to the analysis of power flow direction,the transfer efficiency of the triaxial differential system under different attitude angles is calculated.The 3D model is imported into the ADAMS software,and the motion trajectory simulation analysis of the robot in the pipeline is carried out.The grinding trajectory of the grinding wheel is determined to meet the design requirements.The motion model working in the stepped straight tube is established to verify the change of the pipeline robot.Diameter ability;according to the different attitude angles,the simulation motion is obtained,and the motion curve of the whole machine and the roller in the process of variable diameter under various attitude angles is obtained,and the optimal attitude angle is selected and compared;the simulation of the roller and the grinding wheel is analyzed.Forced,the force curve is obtained,and the rationality of the parameter determination is verified by comparison with the theoretical value.Static mechanical analysis of key components by ANSYS,verifying whether the strength and stiffness of the material are required,and optimizing some parts;performing sixth-order modal analysis on the whole frame and grinding wheel support,and calculating the excitation The frequency is compared to determine that the frequency bands of their resonances do not coincide.