VERTICAL WELDING METHOD IN SEMIAUTOMATIC ARC WELDING OF GAS SHIELDED CONSUMABLE ELECTRODE TYPE

摘要

PURPOSE:To prevent the sagging down of a molten metal in vertical welding and to obtain a smooth weld bead, by providing an auxiliary nozzle in the inner lower part of a gas nozzle, ejecting a gaseous flow of a high velocity therefrom, and applying the gaseous flow to weld metal from below. CONSTITUTION:An auxiliary nozzle 10 is provided below a torch nozzle 7 in vertical welding in automatic arc welding of a gas shielded consumable electrode type. A high velocity gas 11 such as a gas contg. small amts. of carbon dioxide and oxygen than in an ordinary shielding gas or an inert gas is blown from the nozzle 10 to weld metal 3 from below to prevent the sagging down of the metal 3. Upward directed force is applied to the metal 3 by the blowing of such gaseous flow and the solidification of the metal 3 is accelerated. The good multilayered weld zone free from lack of fusion is obtained by the above- mentioned method.