円形はめ込み溶接の殘留応力について

概要

論文の詳細を見る
Circular patch welding, one of the typical restrained welding, frequently causes weld cracking.Hitherto, in general, it has been only known that the greater the size of patch is the safer from the cracking.Furthermore, it is necessary that we should find the range of circular patch diameter will be safe in various thickneses of plate, and what method should be applied to prevent any cracking and our fear in practice.For these purposes, the authors measured the residual stresses on the welded parts of various circular patches by application of trepaning method, and then, compared the each measuring results. Because, we could consider that the cracking on welded part was not always made by the residual stress but had very close relations with it remakably, i.e. always it seemed the greater the residual stress level contained the more possible of cracking, and the smaller the less.We thus could summarize the experimental results that the distribution of the residual stess level showed a peak value about 80 or 100 mm D. patch in each thickness of plates and using of "symmetrical block method" was very effective for low stress level.Also, we find the pre-heating process before welding was not available for reducing of residual stress level, contrary to our expection.
社団法人日本船舶海洋工学会の論文