AC TIG WELDING METHOD AND EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To provide an AC TIG welding method and equipment capable of stably and quickly starting arc in all ranges of welding current. SOLUTION: In the AC TIG welding method in which AC frequency during welding is set higher than commercial frequency and in which AC frequency is set lower in starting an arc than during the welding; a period from the arc start until the welding is constituted of a first period T1 in which an EP period ratio is higher than during the welding and a second period T2 in which AC frequency following this first period is the same as in the first period T1 and in which the EP period ratio is the same as during the welding. COPYRIGHT: (C)2008,JPO&INPIT