The Development Of Automatic Tracking And Grinding Robot For Large Diameter Metal Spiral Pipe Inner Wall Weld

With the national economic development and the continual advancement of the strategic layout for resources integration,the pipeline transport shows a significant demands for the spiral pipe with large diameter.To make the spraying treatment for interior walls of spiral pipe with large diameter easier and improve its surface quality for longer service life,it is necessary to polish the weld line on the interior pipe wall after being welded.The portable angle grinder is generally adopted by domestic pipe manufacturers these days,but it has low efficiency and polishing accuracy as well as significant harms to the worker's health.And since relevant equipment of other countries are special limited pipe robots for import,it's hardly applied for inconvenient purchasing and low cost.Therefore,based on the requirements of relevant enterprises,a pipe robot is particularly designed and developed for the weld line polishing of interior wall of the spiral metal pipe with large diameter,which has important and far-reaching significance in enhancing the polishing quality and efficiency,protecting the workers' health and lowering labor cost.This paper has the main research contents as follows:(1)It briefly introduces the application background of the spiral pipe with large diameter and the research situation of the special robot for interior pipe working at home and abroad,with the research contents and methods adopted in this paper elaborated.(2)It analyzes the weld line distribution condition on the interior wall of the spiral pipe with large diameter and the technical requirements for weld line polishing,and proposes and designs the polishing technique of spiral motion “by segment”.(3)It accomplishes the overall design and outlooks of the pipe robot,including the robot's main supporting device,three axis rotation operation device,grinding feeding device and the only sensing module.Additionally,the supporting part and the driving part are designed in detail,with three schemes proposed for discussion and the selection of related important electric elements verified.(4)A set of open automatic grinding controlling system is designed,integrating weld line automatic tracing system,grinding control with eternal force and effective “continual operation” by multiple working parts within segmental operation.(5)With SolidWorks/Simulation module,the finite element analysis is conducted on the mechanical structure of the pipe robot,obtaining the morphological characteristics of its elements under loading impacts,for instance,hollow rotating shaft addition and the reasonable range of stress deformation of support chassis installation,and verifying the reasonability of the mechanical structure and the reliability of the selected materials.(6)Based on the many-body dynamics simulation platform ADAMS,the motion simulation of the pipe robot under fixed supporting impacts within the pipe is established.By pre-setting sensors on each supporting foot the coordinate moving image of the marked spots in space is acquired.What's more,the feasibility of three-foot power-driven support design is analyzed and verified.