iron-arc

例句：

1. 1.The iron-arc welder is used to join metal parts together.
   铁弧焊机用于将金属部件连接在一起。
2. 2. The arc in the furnace glows brightly, indicating that the metal is molten.
   炉中的电弧发光明亮，表示金属已熔化。
3. 3. The iron-arc torch was used for cutting and shaping metal.
   铁弧焊枪用于切割和成型金属。