包覆电弧熔接

[机] arc welding with covered electrode

bāo fù diàn hú róng jiē ㄅㄠ ㄈㄨˋ ㄉㄧㄢˋ ㄏㄨˊ ㄖㄨㄥˊ ㄐㄧㄝ