Research Of Drilling Technology In Civil Aircraft Automatic Assembly

Due to modern large aircraft structure characteristics with large size,long life, low manufacturing cost and short research cycle, manufacturingtechnology must accordingly meet the need of long life, low cost, and highefficiency. As the most used aircraft connecting parts are of thin-wallstructure with the characteristic of large size, small thickness, complexshape, poor stability, etc., it is hard to guarantee the drilling quality.The burr, produced when drilling, will reduce the hole surface qualityand induce stress concentration around the hole edge seriously, whicheventually affects negatively the structure connection quality and theaircraft assembly efficiency.Automatic drilling/riveting technology will be employed inlarge-scale in the large civil aircraft production. This research focuseson the insufficiency problem in the current process specification. It isof great significance to apply the riveting process in automaticdrilling/riveting technology, so this thesis aims to provide a basictechnical support for large civil aircraft manufacturing. This thesisanalyzes the aircraft assembly process in current, reveals the presentaircraft assembly problems, by which the theoretical issues needed to beresearched are proposed. According to investigation results on the burrgrowth mechanism when drilling the aviation typical aluminum alloythin-wall part, this thesis pointes out the drilling force is the keyfactor in burr formation. And then on the processing region segmentation,this thesis proposes a stratified feed drilling technology, which canoptimize and control the burr formation by controlling the amount of feed.The results of drilling tests show that the stratified feed drillingtechnology can control the burr formation effectively, the drillingquality is notablely improved, and the defects are also reduced.