流れの可視化とガス濃度の分析による解析 : ガスシールドアーク溶接における耐風効果に関する研究(第 3 報)

概要

論文の詳細を見る
In this paper we describe an experimental study of the shielding gas flow state in a still atmosphere and windy conditions by visualization of the flow and analyzing the gas concentration around the nozzle. Then a simple method to obtain the suitable gas flow rate of CO_2 arc welding in windy condition can be suggested. Results of the experiments are summarized as follows. 1) CO_2 gas concentration in the wall jet in a still atmosphere is maximum on the plate surface. It decreases lineally parting from the plate surface and decreases exponentially by increasing of X/d. 2) CO_2 gas concentration of the shielding gas jet in windy conditions is decided by U_0,u_j, H and d. Each curve showing the relation between q_<CO_2>/q_<CO_2>+_<AIR> and U_0/u_j has the similarity throughout the experiment. 3) The suitable gas flow rate of the CO_2 arc welding in windy conditions can be estimated by the (q_<CO_2>/q_<CO_2>+_<AIR>-U_0/U_j) curve with some H/d used in welding. 4) Application of this oil smoke method to visualization of the shielding gas flow is usefull over the wide range of Reynolds number. And this method will be avialble to investigate the shielding gas effect of the narrow-gap welding.
社団法人溶接学会の論文
1978-09-05